The Maternal-Fetal Medicine Units cesarean registry: chorioamnionitis at term and its duration-relationship to outcomes

Correlation between intrapartum CTG findings and interleukin-6 levels in the umbilical cord arterial blood: A prospective cohort study

OBJECTIVE

to investigate the correlation between the intrapartum CardioTocoGraphic (CTG) findings "suggestive of fetal inflammation" ("SOFI") and the interleukin (IL)-6 level in the umbilical arterial blood.

STUDY DESIGN

prospective cohort study conducted at a tertiary maternity unit and including 447 neonates born at term.

METHODS

IL-6 levels were systematically measured at birth from a sample of blood taken from the umbilical artery. The intrapartum CTG traces were retrospectively reviewed by two experts who were blinded to the postnatal umbilical arterial IL-6 values as well as to the neonatal outcomes. The CTG traces were classified into "suggestive of fetal inflammation (SOFI)" and "no evidence of fetal inflammation (NEFI) according to the principles of physiologic interpretation the CTG traces. The CTG was classified as "SOFI" if there was a persistent fetal heart rate (FHR) increase > 10 % compared with the observed baseline FHR observed at the admission or at the onset of labor without any preceding repetitive decelerations. The occurrence of Composite Adverse Outcome (CAO) was defined as Neonatal Intensive Care Unit (NICU) or Special Care Baby Unit (SCBU) admission due to one or more of the following: metabolic acidaemia, Apgar score at 5 min ≤ 7, need of neonatal resuscitation, respiratory distress, tachypnoea/polypnea, jaundice requiring phototherapy, hypotension, body temperature instability, poor perinatal adaptation, suspected or confirmed early neonatal sepsis.

MAIN OUTCOME MEASURES

To compare the umbilical IL-6 values between the cases with intrapartum CTG traces classified as "SOFI" and those classified as "NEFI"; to assess the correlation of umbilical IL-6 values with the neonatal outcome.

RESULTS

43 (9.6 %) CTG traces were categorized as "SOFI"; IL-6 levels were significantly higher in this group compared with the "NEFI" group (82.0[43.4-325.0] pg/ml vs. 14.5[6.8-32.6] pg/mL; p <.001). The mean FHR baseline assessed 1 h before delivery and the total labor length showed an independent and direct association with the IL-6 levels in the umbilical arterial blood (p <.001 and p = 0.005, respectively). CAO occurred in 33(7.4 %) cases; IL-6 yielded a good prediction of the occurrence of the CAO with an AUC of 0.72 (95 % CI 0.61-0.81).

CONCLUSION

Intrapartum CTG findings classified as "SOFI" are associated with higher levels of IL-6 in the umbilical arterial blood.

Clinical chorioamnionitis at term: definition, pathogenesis, microbiology, diagnosis, and treatment

Clinical chorioamnionitis, the most common infection-related diagnosis in labor and delivery units, is an antecedent of puerperal infection and neonatal sepsis. The condition is suspected when intrapartum fever is associated with two other maternal and fetal signs of local or systemic inflammation (eg, maternal tachycardia, uterine tenderness, maternal leukocytosis, malodorous vaginal discharge or amniotic fluid, and fetal tachycardia). Clinical chorioamnionitis is a syndrome caused by intraamniotic infection, sterile intraamniotic inflammation (inflammation without bacteria), or systemic maternal inflammation induced by epidural analgesia. In cases of uncertainty, a definitive diagnosis can be made by analyzing amniotic fluid with methods to detect bacteria (Gram stain, culture, or microbial nucleic acid) and inflammation (white blood cell count, glucose concentration, interleukin-6, interleukin-8, matrix metalloproteinase-8). The most common microorganisms are Ureaplasma species, and polymicrobial infections occur in 70% of cases. The fetal attack rate is low, and the rate of positive neonatal blood cultures ranges between 0.2% and 4%. Intrapartum antibiotic administration is the standard treatment to reduce neonatal sepsis. Treatment with ampicillin and gentamicin have been recommended by professional societies, although other antibiotic regimens, eg, cephalosporins, have been used. Given the importance of Ureaplasma species as a cause of intraamniotic infection, consideration needs to be given to the administration of antimicrobial agents effective against these microorganisms such as azithromycin or clarithromycin. We have used the combination of ceftriaxone, clarithromycin, and metronidazole, which has been shown to eradicate intraamniotic infection with microbiologic studies. Routine testing of neonates born to affected mothers for genital mycoplasmas could improve the detection of neonatal sepsis. Clinical chorioamnionitis is associated with decreased uterine activity, failure to progress in labor, and postpartum hemorrhage; however, clinical chorioamnionitis by itself is not an indication for cesarean delivery. Oxytocin is often administered for labor augmentation, and it is prudent to have uterotonic agents at hand to manage postpartum hemorrhage. Infants born to mothers with clinical chorioamnionitis near term are at risk for early-onset neonatal sepsis and for long-term disability such as cerebral palsy. A frontier is the noninvasive assessment of amniotic fluid to diagnose intraamniotic inflammation with a transcervical amniotic fluid collector and a rapid bedside test for IL-8 for patients with ruptured membranes. This approach promises to improve diagnostic accuracy and to provide a basis for antimicrobial administration.

The Association between Term Chorioamnionitis during Labor and Long-Term Infectious Morbidity of the Offspring

Background: Chorioamnionitis during labor exposes the fetus to an intrauterine state that may alter the future immune response and may expose the offspring to future susceptibility to infectious disease. We evaluated the long-term pediatric infectious morbidity of children born at term to mothers who have chorioamnionitis during labor. Methods: This was a population-based cohort analysis including only term singleton deliveries at a regional tertiary hospital between the years 1991 and 2021. Offspring to mothers with and without a diagnosis of chorioamnionitis during labor were compared. Offspring hospitalizations up to the age of 18 years involving infectious morbidity were evaluated using the Kaplan-Meier survival curve and a Cox regression model to control possible confounders. Results: A total of 331,598 deliveries were included, 988 (0.3%) of which were of mothers diagnosed with chorioamnionitis during labor. All infectious morbidity rates included in the analysis were comparable between groups. The Kaplan-Meier survival curves were similar for both groups (log-rank = 0.881) and the multivariable analysis ascertained that chorioamnionitis during labor was not a risk factor for offspring's long-term infectious morbidity (HR 0.929, 95%CI 0.818-1.054, p = 0.254). Conclusions: In our cohort, term chorioamnionitis during labor was not associated with a higher risk of pediatric hospitalization due to infections. The infectious/inflammatory state during labor did not expose nor increase the susceptibility of the term offspring to future infectious morbidity.

Fetal Tachycardia in the Setting of Maternal Intrapartum Fever and Perinatal Morbidity

OBJECTIVE

 The fetal consequences of intrapartum fetal tachycardia with maternal fever or clinical chorioamnionitis are not well studied. We evaluated the association between perinatal morbidity and fetal tachycardia in the setting of intrapartum fever.

STUDY DESIGN

 Secondary analysis of a multicenter randomized control trial that enrolled 5,341 healthy laboring nulliparous women ≥36 weeks' gestation. Women with intrapartum fever ≥ 38.0°C (including those meeting criteria for clinical chorioamnionitis) after randomization were included in this analysis. Isolated fetal tachycardia was defined as fetal heart rate (FHR) ≥160 beats per minute for at least 10 minutes in the absence of other FHR abnormalities. FHR abnormalities other than tachycardia were excluded from the analysis. The primary outcome was a perinatal composite (5-minute Apgar's score ≤3, intubation, chest compressions, or mortality). Secondary outcomes included low arterial cord pH (pH < 7.20), base deficit ≥12, and cesarean delivery.

RESULTS

 A total of 986 (18.5%) of women in the trial developed intrapartum fever, and 728 (13.7%) met criteria to be analyzed; of these, 728 women 336 (46.2%) had maternal-fetal medicine (MFM) reviewer-defined fetal tachycardia, and 349 of the 550 (63.5%) women during the final hour of labor had validated software (PeriCALM) defined fetal tachycardia. After adjusting for confounders, isolated fetal tachycardia was not associated with a significant difference in the composite perinatal outcome (adjusted odds ratio [aOR] = 3.15 [0.82-12.03]) compared with absence of tachycardia. Fetal tachycardia was associated with higher odds of arterial cord pH <7.2, aOR = 1.48 (1.01-2.17) and of infants with a base deficit ≥ 12, aOR = 2.42 (1.02-5.77), but no significant difference in the odds of cesarean delivery, aOR = 1.33 (0.97-1.82).

CONCLUSION

 Fetal tachycardia in the setting of intrapartum fever or chorioamnionitis is associated with significantly increased fetal acidemia defined as a pH <7.2 and base excess ≥12 but not with a composite perinatal morbidity.

KEY POINTS

· The perinatal outcomes associated with fetal tachycardia in the setting of maternal fever are undefined.. · Fetal tachycardia was not significantly associated with perinatal morbidity although the sample size was limited.. · Fetal tachycardia was associated with an arterial cord pH <7.2 and base deficit of 12 or greater..

Association between intrapartum antibiotic prophylaxis for Group B Streptococcus colonization and clinical chorioamnionitis among patients undergoing induction of labor at term

BACKGROUND

Rectovaginal colonization with Group B Streptococcus during pregnancy has historically been shown to be associated with an increased risk of clinical chorioamnionitis and peripartum infectious morbidity.

OBJECTIVE

Newer observational data in the era of intrapartum antibiotic prophylaxis suggest a possible reversal of this association; however, it is unclear if this is related to differences in labor management for those with and without Group B Streptococcus colonization. We therefore sought to assess the association between intrapartum antibiotic prophylaxis for Group B Streptococcus colonization and clinical chorioamnionitis within the context of a randomized induction of labor trial with a standardized labor protocol.

STUDY DESIGN

We performed an exploratory secondary analysis of a randomized trial of patients undergoing term induction at a tertiary care center. Patients received third trimester Group B Streptococcus screening and intrapartum antibiotic prophylaxis as routine care. Group B Streptococcus detection was performed using a carrot broth-enhanced subculture to Group B Streptococcus Detect approach (Hardy Diagnostics, Santa Maria, CA). Labor management was protocolized per the trial. Patients with unknown Group B Streptococcus status or who did not receive intrapartum antibiotic prophylaxis, if indicated, were excluded. The primary outcome was diagnosis of clinical chorioamnionitis, compared between patients who received intrapartum antibiotic prophylaxis for known Group B Streptococcus positive status (by culture, history, or Group B Streptococcus bacteriuria) and those who were Group B Streptococcus negative and did not receive intrapartum antibiotic prophylaxis. Secondary outcomes included postpartum endometritis, wound infection, a composite maternal peripartum infectious morbidity, and neonatal outcomes.

RESULTS

A total of 491 patients were enrolled in the trial. Of these, 466 had a known Group B Streptococcus status and received or did not receive intrapartum antibiotic prophylaxis accordingly and were included in this analysis: 292 (62.7%) were Group B Streptococcus negative and did not receive intrapartum antibiotic prophylaxis, and 174 (37.3%) were Group B Streptococcus positive and received intrapartum antibiotic prophylaxis. The majority of patients were Non-Hispanic Black (78.1%) and nulliparous (59.7%). There were no differences in demographic, clinical, induction or labor characteristics between groups. Patients who were Group B Streptococcus positive had a 49% lower rate of clinical chorioamnionitis (8.1% vs 14.7%, odds ratio, 0.51; P=.03) and a lower rate of peripartum infectious morbidity (8.1% vs 15.8%, odds ratio, 0.47; P=.02) compared to those who were Group B Streptococcus negative. Infants born to patients who were Group B Streptococcus positive were significantly less likely to be admitted to the neonatal intensive care unit (3.4% vs 15.1%, P<.001).

CONCLUSION

Although Group B Streptococcus colonization has historically been considered a risk factor for clinical chorioamnionitis, in the era of universal antibiotic prophylaxis for Group B Streptococcus positive patients, our findings support the point that intrapartum antibiotic prophylaxis for Group B Streptococcus positivity is associated with lower rates of clinical chorioamnionitis and peripartum infectious morbidity among patients undergoing induction with protocolized labor management. These findings demonstrate that intrapartum antibiotic prophylaxis for Group B Streptococcus may protect against perinatal infectious morbidity, a phenomenon that warrants further investigation.

Clinical chorioamnionitis at term is characterized by changes in the plasma concentration of CHCHD2/MNRR1, a mitochondrial protein

OBJECTIVE

Mitochondrial dysfunction was observed in acute systemic inflammatory conditions such as sepsis and might be involved in sepsis-induced multi-organ failure. Coiled-Coil-Helix-Coiled-Coil-Helix Domain Containing 2 (CHCHD2), also known as Mitochondrial Nuclear Retrograde Regulator 1 (MNRR1), a bi-organellar protein located in the mitochondria and the nucleus, is implicated in cell respiration, survival, and response to tissue hypoxia. Recently, the reduction of the cellular CHCHD2/MNRR1 protein, as part of mitochondrial dysfunction, has been shown to play a role in the amplification of inflammatory cytokines in a murine model of lipopolysaccharide-induced systemic inflammation. The aim of this study was to determine whether the plasma concentration of CHCHD2/MNRR1 changed during human normal pregnancy, spontaneous labor at term, and clinical chorioamnionitis at term.

METHODS

We conducted a cross-sectional study that included the following groups: 1) non-pregnant women (n = 17); 2) normal pregnant women at various gestational ages from the first trimester until term (n = 110); 3) women at term with spontaneous labor (n = 50); and 4) women with clinical chorioamnionitis at term in labor (n = 25). Plasma concentrations of CHCHD2/MNRR1 were assessed by an enzyme-linked immunosorbent assay.

RESULTS

1) Pregnant women at term in labor with clinical chorioamnionitis had a significantly higher plasma CHCHD2/MNRR1 concentration than those in labor without chorioamnionitis (p = .003); 2) CHCHD2/MNRR1 is present in the plasma of healthy non-pregnant and normal pregnant women without significant differences in its plasma concentrations between the two groups; 3) there was no correlation between maternal plasma CHCHD2/MNRR1 concentration and gestational age at venipuncture; and 4) plasma CHCHD2/MNRR1 concentration was not significantly different in women at term in spontaneous labor compared to those not in labor.

CONCLUSIONS

CHCHD2/MNRR1 is physiologically present in the plasma of healthy non-pregnant and normal pregnant women, and its concentration does not change with gestational age and parturition at term. However, plasma CHCHD2/MNRR1 is elevated in women at term with clinical chorioamnionitis. CHCHD2/MNRR1, a novel bi-organellar protein located in the mitochondria and the nucleus, is released into maternal plasma during systemic inflammation.

Changes in fetal baroreceptor sensitivity during intrauterine inflammation in preterm fetal sheep

OBJECTIVE

Baroreflex is a regulatory mechanism that slows the fetal heart rate. This study aimed to investigate the effects of lipopolysaccharide (LPS)-induced endotoxemia on fetal baroreceptor sensitivity in preterm fetal sheep.

METHODS

The changes in fetal baroreceptor sensitivity were measured in seven chronically instrumented preterm fetal sheep. Fetal baroreceptor sensitivity was measured in three phases: (A) control phase, defined as the 24 h before the first injection of LPS; (B) acute phase, defined as the 24 h between the first and second injections of LPS; and (C) fetal acidosis phase, defined as the time from the second LPS injection until intrauterine fetal death. Histological examinations of the fetal membrane and umbilical cord were also conducted.

RESULTS

Each fetus developed metabolic acidosis after the second injection of LPS. The fetuses died 24.7 (SD = 6.1) hours after the second injection of LPS. Both the umbilical cord and fetal membranes showed histological evidence of severe inflammation. In total, 163 fetal baroreceptor measurements were performed in this experiment (A, n = 77 times; B, n = 60 times; C, n = 26 times). Fetal baroreceptor sensitivity showed significant differences in all three phases (A: 2.7 [SD = 0.2]; B: 2.5 [SD = 0.2]; and C: 1.5 [SD = 0.2]). Post hoc tests showed that baroreceptor sensitivity in the acidosis phase had decreased significantly compared to that in the control and acute phases (p<.001 and p=.002, respectively).

CONCLUSIONS

Fetal baroreceptor sensitivity decreased during fetal acidosis induced by LPSs.

Neonatal immune cells have heightened responses following in-utero exposure to chorioamnionitis or COVID-19

BACKGROUND

Chorioamnionitis alters neonatal immune responses. Gestational COVID-19 infection is associated with adverse pregnancy outcomes, but its impact on neonatal immunity is unclear. We hypothesized that gestational COVID-19 exposure would result in exaggerated neonatal immune responses, similar to chorioamnionitis-exposed neonates.

METHODS

Term umbilical cord blood mononuclear cells (CBMCs) were isolated from neonates exposed to chorioamnionitis, gestational COVID-19 or unexposed controls. CBMCs were cultured and stimulated with heat-killed Escherichia coli, Streptococcus agalactiae or Staphylococcus epidermidis. A multiplexed protein assay was used to measure cytokine levels in cell culture supernatants and flow cytometry was used to evaluate cellular-level cytokine expression.

RESULTS

Both chorioamnionitis-exposed and COVID-19 exposed CBMCs demonstrated upregulation of IL-1β and IL-6 compared to unexposed CBMCs, while only COVID-19 exposure resulted in IL-8 upregulation. There were no differences between chorioamnionitis-exposed and COVID-19 exposed CBMCs when these groups were directly compared. Flow cytometry demonstrated immune cell subset specific differences in cytokine expression between the exposure groups.

CONCLUSION

The fetal/neonatal response to maternal inflammation differed based on immune cell subset and etiology of inflammation, but the global neonatal cytokine responses were similar between exposure groups. This suggests that targeting perinatal inflammation rather than the specific etiology may be a possible therapeutic approach.

IMPACT

Neonatal immune cells have similar pathogen-associated global cytokine responses, but different cell-level immune responses, following in-utero exposure to chorioamnionitis or COVID-19. This is the first study to directly compare immune responses between neonates exposed to chorioamnionitis and COVID-19. This suggests that the fetal/neonatal cellular response to perinatal inflammation differs based on the etiology and severity of maternal inflammation, but still results in a similar overall inflammatory profile regardless of the cause of perinatal inflammation.

Antibiotic treatment of women with isolated intrapartum fever vs clinical chorioamnionitis: maternal and neonatal outcomes

BACKGROUND

Clinical chorioamnionitis refers to the presence of maternal fever (≥38°C) and at least 2 clinical signs: (1) maternal tachycardia (>100 bpm), (2) fetal tachycardia (>160 bpm), (3) maternal leukocytosis >15,000/mm2, (4) purulent vaginal discharge, and (5) uterine tenderness. Few data exist to guide the appropriate management of women with isolated intrapartum fever in the absence of other clinical signs suggesting chorioamnionitis.

OBJECTIVE

This study compared maternal and neonatal infectious outcomes and microbiological outcomes between women with isolated intrapartum fever and women with clinical chorioamnionitis.

STUDY DESIGN

This 10-year retrospective study included all the laboring women at our institution, at ≥34 weeks of gestation, with a singleton pregnancy and body temperature of ≥38.0°C, with or without other evidences of infection. According to our department protocol, women with isolated intrapartum fever received intravenous ampicillin, whereas women with clinical chorioamnionitis received intravenous ampicillin plus gentamicin. The primary outcome was puerperal endometritis, compared between women with isolated intrapartum fever (treated with ampicillin) and women with clinical chorioamnionitis (treated with ampicillin plus gentamicin). The secondary maternal outcomes consisted of (1) maternal clinical outcomes, such as cesarean delivery, surgical site infection, postpartum hemorrhage, and postpartum length of stay, and (2) microbiological studies, including positive chorioamniotic membrane swabs and blood culture. Among the secondary neonatal outcomes were early-onset sepsis, neonatal intensive care unit admission, and length of stay. Of note, 2 multivariate logistic regression models were created. A model aimed to predict puerperal endometritis controlled for gestational age of >41 weeks, diabetes mellitus, obesity, positive group B streptococcus status, rupture of membrane ≥18 hours, meconium staining, positive chorioamniotic membrane swabs, cesarean delivery, and empiric postdelivery antibiotic administration. A model aimed to predict neonatal early-onset sepsis controlled for gestational age of 34 to 37 weeks, positive group B streptococcus status, rupture of membrane ≥18 hours, and positive chorioamniotic membrane swabs.

RESULTS

Overall, 458 women met the inclusion criteria. Compared with women with clinical chorioamnionitis (n=231), women with isolated intrapartum fever (n=227) had higher rates of puerperal endometritis (3.9% vs 8.8%; P=.03), early-onset sepsis (0.4% vs 4.4%; P=.005), positive chorioamniotic membrane swabs (46.3% vs 63.9%; P<.001), and ampicillin-resistant Escherichia coli (35.5% vs 48.9%; P=.033). The rate of group B streptococcus-positive chorioamniotic membrane swabs was similar between the groups. In a subanalysis of women with negative or unknown group B streptococcus status, the puerperal endometritis and neonatal early-onset sepsis rates were higher among women with isolated intrapartum fever than women with suspected chorioamnionitis (8.7% vs 3.3% [P=.041] and 4.1% vs 0% [P<.001], respectively). In 2 multivariate analysis models, among women with isolated intrapartum fever treated with ampicillin compared with those with clinical chorioamnionitis treated with ampicillin and gentamicin, the odds ratio of antibiotic treatment of endometritis was 2.65 (95% confidence interval, 1.06-6.62; P=.036), and the odds ratio of neonatal early-onset sepsis was 8.33 (95% confidence interval, 1.04-60.60; P=.045).

CONCLUSION

Women with intrapartum fever, with or without other signs of infection, were at increased risk of maternal and neonatal complications. The use of ampicillin as a sole agent in isolated intrapartum fever might promote ampicillin-resistant E coli growth in the chorioamniotic membranes and consequently lead to puerperal endometritis and early-onset sepsis. In this context, a broad-range antibiotic should be considered.

Chorioamnionitis: An Update on Diagnostic Evaluation

Chorioamnionitis remains a major cause of preterm birth and maternal and neonatal morbidity. We reviewed the current evidence for the diagnostic tests of chorioamnionitis and how this relates to clinical practice today. A comprehensive literature search and review was conducted on chorioamnionitis and intra-uterine inflammation. Data from randomized control trials and systematic reviews were prioritized. This review highlights that sterile inflammation plays an important role in chorioamnionitis and that the current tests for chorioamnionitis including clinical criteria, maternal plasma and vaginal biomarkers lack diagnostic accuracy. Concerningly, these tests often rely on detecting an inflammatory response after damage has occurred to the fetus. Care should be taken when interpreting current investigations for the diagnosis of chorioamnionitis and how they guide obstetric/neonatal management. There is an urgent need for further validation of current diagnostic tests and the development of novel, accurate, minimally invasive tests that detect subclinical intra-uterine inflammation.

Risk of disseminated intravascular coagulation in postpartum hemorrhage associated with intrauterine infection

OBJECTIVE

To evaluate the risk of disseminated intravascular coagulation (DIC) in postpartum hemorrhage (PPH) associated with intrauterine infection.

MATERIAL AND METHODS

A retrospective cohort study of pregnancies complicated by PPH performed at a tertiary academic center in France from 2017 through 2021. Patients giving birth after 22 weeks of gestation with PPH were eligible. Patients with a PPH associated with an intrauterine infection were compared to patients with a PPH without intrauterine infection. Intrauterine infection was defined by a composite criterion available at delivery. DIC was defined by a specific pregnancy DIC score. The association between DIC and intrauterine infection was assessed by logistic regression. The causal effect of intrauterine infection on DIC was estimated by mediation analysis.

RESULTS

Of 2,093 patients with PPH, 49 exposed to a clinical intrauterine infection were compared to 49 unexposed patients. The rate of DIC was higher in patients with than without infection (22 (45.8%) vs. 7 (14.6%), P = .001), and coagulation anomalies occurred sooner in patients with than without infection (7, 2-11 h vs. 14, 9-19 h, P < .001). In the multivariate analysis, intrauterine infection was the only factor independently associated with DIC (adjusted odds ratio 5.01, 95% CI 1.83-13.73). Mediation analysis showed that 14% (95% CI, 0-50%) of this association between intrauterine infection and DIC was mediated by severe PPH, and 86% resulted from the direct effect of intrauterine infection on DIC.

CONCLUSION

In PPH, intrauterine infection had a major direct effect on the occurrence, timing, and severity of DIC.

Postpartum Hemorrhage-Epidemiology, Risk Factors, and Causes

The incidence of postpartum hemorrhage (PPH) is increasing worldwide and in the United States. Coinciding, is the increased rate of severe maternal morbidity with blood transfusion in the United States over the past 2 decades. Consequences of PPH can be life-threatening and carry significant cost burden to the health care system. This review will discuss the current trends, distribution, and risk factors for PPH. Causes of PPH will be explored in detail.

Single versus dual antibiotic regimen in women with term prolonged rupture of membranes and intrapartum fever: a retrospective study

OBJECTIVES

The impact of E. coli in causing peripartum infections has been increasing due to rising ampicillin resistance. In this study, we compared maternal and neonatal outcomes of women with prolonged rupture of membranes (ROM >18h) and intrapartum fever, according to two antibiotic regimens they received, and describe the bacterial distribution focusing on risk factors for Enterobacteriaceae-related infectious morbidity.

STUDY DESIGN

This 10-year retrospective study of women with ROM >18h and intrapartum fever included 62 women who were treated with ampicillin and gentamicin due to suspected intraamniotic infection and 79 without these signs who were treated with ampicillin alone. The primary outcomes were endometritis and neonatal early-onset sepsis (EOS) rates. Outcomes were compared using univariate and multivariate analyses.

RESULTS

Among women who received ampicillin alone compared with dual therapy, rates were higher of endometritis (17% vs. 3%, p<0.001), neonatal early onset sepsis (7.5% vs. 0%, p=0.03), Enterobacteriaceae positive placental swab culture (67.9% vs. 15.7%, p<0.001), and histopathological subchorionitis (25.3% vs. 8.0%, p=0.008). Over 83% of Enterobacteriaceae isolates were ampicillin-resistant. Gestational age at delivery >41 weeks, meconium at delivery, ROM >24h and treatment with a single antibiotic agent were associated with the presence of a positive Enterobacteriaceae placental swab culture.

CONCLUSION

Ampicillin compared to dual treatment in women with prolonged ROM and fever might promote the growth of ampicillin-resistant Enterobacteriaceae (including E.coli) and increase risks of maternal and neonatal infectious morbidity.

Racial and Ethnic Disparities in Adverse Perinatal Outcomes at Term

OBJECTIVE

 This study aimed to evaluate whether racial and ethnic disparities in adverse perinatal outcomes exist at term.

STUDY DESIGN

 We performed a secondary analysis of a multicenter observational study of 115,502 pregnant patients and their neonates (2008-2011). Singleton, nonanomalous pregnancies delivered from 37 to 41 weeks were included. Race and ethnicity were abstracted from the medical record and categorized as non-Hispanic White (White; referent), non-Hispanic Black (Black), non-Hispanic Asian (Asian), or Hispanic. The primary outcome was an adverse perinatal composite defined as perinatal death, Apgar score < 4 at 5 minutes, ventilator support, hypoxic-ischemic encephalopathy, subgaleal hemorrhage, skeletal fracture, infant stay greater than maternal stay (by ≥ 3 days), brachial plexus palsy, or facial nerve palsy.

RESULTS

 Of the 72,117 patients included, 48% were White, 20% Black, 5% Asian, and 26% Hispanic. The unadjusted risk of the primary outcome was highest for neonates of Black patients (3.1%, unadjusted relative risk [uRR] = 1.16, 95% confidence interval [CI]: 1.04-1.30), lowest for neonates of Hispanic patients (2.1%, uRR = 0.80, 95% CI: 0.71-0.89), and no different for neonates of Asian (2.6%), compared with those of White patients (2.7%). In the adjusted model including age, body mass index (BMI), smoking, obstetric history, and high-risk pregnancy, differences in risk for the primary outcome were no longer observed for neonates of Black (adjusted relative risk [aRR] = 1.06, 95% CI: 0.94-1.19) and Hispanic (aRR = 0.92, 95% CI: 0.81-1.04) patients. Adding insurance to the model lowered the risk for both groups (aRR = 0.85, 95% CI: 0.75-0.96 for Black; aRR = 0.68, 95% CI: 0.59-0.78 for Hispanic).

CONCLUSION

 Although neonates of Black patients have the highest frequency of adverse perinatal outcomes at term, after adjustment for sociodemographic factors, this higher risk is no longer observed, suggesting the importance of developing strategies that address social determinants of health to lessen extant health disparities.

KEY POINTS

· Term neonates of Black patients have the highest crude frequency of adverse perinatal outcomes.. · After adjustment for confounders, higher risk for neonates of Black patients is no longer observed.. · Disparities in outcomes are strongly related to insurance status..

Maternal plasma cytokines and the subsequent risk of uterine atony and postpartum hemorrhage

OBJECTIVES

To determine whether the maternal plasma concentrations of cytokines are higher in pregnant women with postpartum hemorrhage (PPH) compared to pregnant women without PPH.

METHODS

A retrospective case-control study included 36 women with PPH and 72 matched controls. Cases and controls were matched for gestational age at delivery, labor status, delivery route, parity, and year of sample collection. Maternal plasma samples were collected up to 3 days prior to delivery. Comparison of the plasma concentrations of 29 cytokines was performed by using linear mixed-effects models and included adjustment for covariates and multiple testing. A false discovery rate adjusted p-value <0.1 was used to infer significance. Random forest models with evaluation by leave-one-out and 9-fold cross-validation were used to assess the combined value of the proteins in predicting PPH.

RESULTS

Concentrations of interleukin (IL)-16, IL-6, IL-12/IL-23p40, monocyte chemotactic protein 1 (MCP-1), and IL-1β were significantly higher in PPH than in the control group. This difference remained significant after adjustment for maternal age, clinical chorioamnionitis, and preeclampsia. Multi-protein random forest proteomics models had moderate cross-validated accuracy for prediction of PPH [area under the ROC curve, 0.69 (0.58-0.81) by leave-one-out cross validation and 0.73 (0.65-0.81) by 9-fold cross-validation], and the inclusion of clinical and demographic information did not increase the prediction performance.

CONCLUSIONS

Pregnant women with severe PPH had higher median maternal plasma concentrations of IL-16, IL-6, IL-12/IL-23p40, MCP-1, and IL-1β than patients without PPH. These cytokines could serve as biomarkers or their pathways may be therapeutic targets.

Assessment of labor progress by ultrasound vs manual examination: a randomized controlled trial

BACKGROUND

Assessment of labor progress via digital examination is considered the standard of care in most delivery rooms. However, this method can be stressful, painful, and imprecise, and multiple examinations increase the risk for chorioamnionitis. Intrapartum ultrasound was found to be an objective, noninvasive tool to monitor labor progression.

OBJECTIVE

This study aimed to investigate whether, among nulliparous women, the use of intrapartum ultrasound can reduce the rate of intrapartum fever by reducing the number of digital examinations.

STUDY DESIGN

This was a prospective, randomized controlled trial in term nulliparas admitted with prelabor rupture of membranes, induction of labor, or in latent phase of labor with a cervical dilation of <4 cm. Women were randomized into 1 of the following 2 arms: (1) labor progress assessed by ultrasound, avoiding digital examinations as much as possible; and (2) control group in which labor progression was assessed according to the regular protocol. Before the study, all labor ward physicians underwent training in intrapartum ultrasound.

RESULTS

A total of 90 women were randomized to the ultrasound group and 92 were randomized to the control group. When compared with the control group, the ultrasound group had significantly lower rates of intrapartum fever (11.1% vs 26.1%; P=.01), clinical chorioamnionitis (3.3% vs 16.5%; P>.01), and histologic chorioamnionitis (2.2% vs 9.8%; P=.03). The median number of digital examinations was significantly lower in the ultrasound group (5; interquartile range, 4-6) than in the control group (8; interquartile range, 6-10; P<.01). The median number of digital examinations per hour in the ultrasound group was significantly lower than in the control group (0.2 vs 0.4; P<.01). The induction rates, time from admission to delivery, mode of delivery, Apgar score at 5 minutes, and neonatal intensive care unit admission rates did not differ significantly between the groups.

CONCLUSION

The use of intrapartum ultrasound lessens the total number of digital examinations needed to be performed during labor and, consequently, the incidence of intrapartum fever and chorioamnionitis are reduced. No adverse effects on labor progression and short-term maternal or neonatal outcomes were noted.

Placental clearance not synthesis tempers exaggerated pro-inflammatory cytokine response in neonates exposed to chorioamnionitis

BACKGROUND

The source and clearance of cytokines in the fetal circulation in term pregnancies complicated by chorioamnionitis remains unclear as are the contributions of placental transport, synthesis, and clearance. The objectives of the study were to determine (1) fetal and/or placental contributions to synthesis and/or clearance of inflammatory and anti-inflammatory cytokines in term pregnancies complicated by chorioamnionitis and (2) whether this differs in pregnancies further complicated by fetal hypoxia.

METHODS

Prospective cohort study of pregnancies >37 weeks gestational age that included: Group 1, uncomplicated cesarean delivery without labor (n = 20); Group 2, uncomplicated vaginal delivery (n = 30); Group 3, pregnancies complicated by chorioamnionitis (n = 10); Group 4, complicated by chorioamnionitis + fetal hypoxia (n = 10). Umbilical arterial (UmA) and venous (UmV) blood were assayed for IL-1β, IL-2, IL-6, IL-8, TNFα, and IL-10.

RESULTS

IL-6 and IL-8 were below assay detection in UmA and UmV blood in Group 1 and increased in Group 2 (P < 0.01), UmA»UmV (P < 0.01). Their concentrations increased further in Groups 3 and 4 (P = 0.003), UmA»UmV. Placental clearance was concentration dependent that approaches saturation in the presence of chorioamnionitis.

CONCLUSIONS

Marked increases in fetal synthesis of IL-6 and IL-8 occur in chorioamnionitis. Synthesis increase further when complicated by fetal hypoxia. Cytokine removal occurs via placental concentration-dependent mechanisms, potentially contributing to adverse fetal effects.

IMPACT

The source and role of the placenta in synthesis and/or clearance of inflammatory mediators in term pregnancies complicated by clinical chorioamnionitis are unclear; however, conventional wisdom suggests the placenta is their source. This is the first study demonstrating that circulating concentrations of fetal IL-6 and IL-8 in clinical chorioamnionitis ± birth asphyxia in term pregnancies are of fetal origin. Circulating fetal inflammatory cytokines are cleared by concentration-dependent placental mechanisms that are nearly saturated in chorioamnionitis ± fetal hypoxia. These observations provide additional insight into understanding the fetal immune response in term pregnancies complicated by clinical chorioamnionitis.

Actualidad en corioamnionitis

La corioamnionitis se ha relacionados con desenlaces desfavorables en el período prenatal y neonatal (abortos, parto pretérmino, sepsis neonatal, entre otros), además de implicaciones a largo plazo en la infancia, tales como alteraciones en el coeficiente intelectual. Por esta razón es de vital importancia el diagnóstico histopatológico oportuno. En este artículo se revisará el abordaje histopatológico de la corioamnionitis, su estadificación e implicaciones clínicas.

Effect of gestational age at first delivery and interpregnancy interval on the recurrence of clinical chorioamnionitis

BACKGROUND

There is an increased odds of having a recurrence of clinical chorioamnionitis in patients with a diagnosis of clinical chorioamnionitis compared with those without clinical chorioamnionitis in a previous pregnancy. However, it is unclear how gestational age at delivery of the first pregnancy or interpregnancy interval may contribute to this increased risk.

OBJECTIVE

This study aimed to evaluate how gestational age of delivery in a first pregnancy and interpregnancy interval affect the odds of recurrent clinical chorioamnionitis.

STUDY DESIGN

Using maternally linked birth record files, Nulliparous patients from California with at least 2 consecutive deliveries between the gestational ages of 20 and 44 weeks from 2007 to 2012 were identified. The rates of clinical chorioamnionitis in the second pregnancy for patients with clinical chorioamnionitis vs those without clinical chorioamnionitis in the first pregnancy, stratified by the gestational age at delivery of the first pregnancy were determined. As a secondary analysis, the analysis by interpregnancy interval (<18 months vs ≥18 months) was stratified. Corresponding crude and adjusted odds ratios for each stratum were calculated to assess the association of clinical chorioamnionitis in the first and second pregnancies.

RESULTS

Among 31,571 nulliparous patients with clinical chorioamnionitis in the first pregnancy, the frequency of clinical chorioamnionitis in the next pregnancy was 4.0% (1257 cases). This was in comparison with the 1.0% (9177 of 896,154) of nulliparous patients without clinical chorioamnionitis in the first pregnancy who were diagnosed with clinical chorioamnionitis in the next pregnancy (adjusted odds ratio, 2.78; 95% confidence interval, 2.61-2.96). The absolute frequency of recurrence was the highest (54 cases [8.2%]) in those who delivered at 20 to 24 weeks of gestation in the first pregnancy with the diagnosis of clinical chorioamnionitis (adjusted odds ratio, 1.76; 95% confidence interval, 1.25-2.48). For pregnancies delivered at term in the first pregnancy, the frequency of clinical chorioamnionitis in the next pregnancy was higher in those diagnosed with clinical chorioamnionitis in the first pregnancy than in those without clinical chorioamnionitis in the first pregnancy (4.0% vs 1.0%; adjusted odds ratio, 2.85; 95% confidence interval, 2.66-3.05). An interpregnancy interval of <18 months was not associated with increased odds of recurrent clinical chorioamnionitis.

CONCLUSION

The odds of recurrence of clinical chorioamnionitis were the strongest when a patient delivered in the term to postterm period in the first pregnancy, with the absolute risk being the highest when the first pregnancy was delivered in the periviable period (20-24 weeks of gestation). The interpregnancy interval did not seem to modify the risk of recurrent clinical chorioamnionitis.

Chorioamnionitis and Its Complications: A Cross-Sectional Study to Assess the Awareness of Married Women in Jeddah

Background: Chorioamnionitis (CA) is a common pregnancy complication characterized by inflammation of the placental membranes and chorion. To our knowledge, there are limited studies evaluating the awareness of CA and its complications among women in Jeddah, Saudi Arabia. This study aimed to determine the awareness of married women in Jeddah toward CA and its complications.

Materials and methods: This cross-sectional study was conducted between March 2021 and August 2021. It involved 406 women who were or have been married in Jeddah, Saudi Arabia. Data were obtained via an online survey and analyzed using IBM SPSS Statistics version 24 (IBM Corp., Armonk, NY). Different statistical tests were used for data analysis, including percentages, mean, frequency, and chi-square. Content validity and reliability were checked. Based on a woman's knowledge score, the score was classified into three levels: good knowledge level (score: 9-12), fair knowledge level (score: 5-8), and poor knowledge level (score: 0-4).

Results: Of the total number of women who participated in the study, most of them had a poor knowledge score about CA complications (49.95%), and only 8.1% had good knowledge. Among the women, 25% had previously heard about CA, while only 2.5% were diagnosed with CA, and 50% of these women delivered by cesarean section. Analysis showed a significant relationship between women who had CA and their birth method (p = 0.000). However, there was a nonsignificant difference between the females' knowledge and their age (p = 0.297), or their level of education (p = 0.099).

Conclusion: The study concluded that there was a poor level of knowledge regarding CA and its complications among women who experienced pregnancy.

Suspected clinical chorioamnionitis with peak intrapartum temperature <380C: the prevalence of confirmed chorioamnionitis and short term neonatal outcome

Background

Chorioamnionitis (CA) affects up to 3.9% of all deliveries worldwide and is one of the leading causes of early-onset neonatal sepsis. Fever≥38⁰C is an essential criterion for the diagnosis of clinical CA. Obstetricians frequently take the maternal risk factors into consideration, and many mothers are treated as CA even with peak intrapartum temperature (PIT) between 37.6⁰C to 37.9⁰C if they have other clinical signs and risk factors.

Aim

To estimate the prevalence of confirmed chorioamnionitis and adverse neonatal outcomes among those mothers with PIT below 38⁰C.

Materials and methods

Retrospective chart review among mothers delivered at Al-Wakra Hospital, Qatar, between1^stJanuary2016 to 31^stDecember 2019 with a clinical suspicion of CA.

Results

Among 21,471 mothers, 442 were suspected of having CA (2.06%, 95% CI 1.88 to 2.26%). After exclusions, 415 were included in the study, 203(48.9%) mothers had PIT between 37.6-37.9⁰C. There was no significant difference in the rate of confirmed CA between the low (<38⁰C) and higher (≥38⁰C) temperature groups (25.4%Vs.31.3%, OR0.75, 95%CI0.46-1.25 , p.262). More patients in the low-temperature group received paracetamol for PIT between 37.6 to 37.9 ⁰C, while it was less frequently used for such milder elevation in higher temperature group (88.2%Vs.38.9%, OR11.69, 95% CI 6.46-2.15, p <.001).

Conclusion

The incidence of suspected clinical CA in our institution was within the international rates. Although nearly half of the mothers with suspected clinical CA had peak temperature below the recommended diagnostic criteria, the rate of confirmed CA and neonatal outcome was not significantly different from those with PIT≥38⁰C. Early antipyretic use might have affected further elevation of temperature.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03239-9.

Outcomes associated with antibiotic administration for isolated maternal fever in labor

BACKGROUND

The American College of Obstetricians and Gynecologists currently recommends that antibiotic treatment should be considered for women with isolated maternal fevers during labor. However, there is little known about the maternal and neonatal impact of antibiotic treatment in this scenario.

OBJECTIVE

We sought to assess the outcomes in women with a nonsustained, isolated maternal fever treated with antibiotics and compare it with expectant management.

STUDY DESIGN

This was a retrospective cohort study of laboring women with a singleton gestation at term and a single temperature of between 38.0°C and 38.9°C without other evidence of infection (leukocytosis >15,000/mm³, fetal tachycardia, malodorous amniotic fluid, suspected alternate source of infection) at a tertiary teaching hospital. A contemporaneously maintained, validated obstetrical database was used to identify women for our cohort. Women with rheumatologic or renal disease, nongestational diabetes, preterm labor, placental abruption, vaginal bleeding, HIV, malpresentation, and fetal anomalies were excluded. The primary outcome was a postpartum fever above 38.0°C. Secondary maternal outcomes were treatment for postpartum endometritis, uterine atony, postpartum hemorrhage, admission to the intensive care unit, and postpartum length of stay. Secondary neonatal outcomes were neonatal intensive care unit admission, 5-minute Apgar score of <7, 5-minute Apgar score of <4, neonatal intensive care unit length of stay, and neonatal antibiotic administration. The results were compared using univariable and multivariable analyses.

RESULTS

From January 1, 2015, to December 31, 2018, 359 women were identified; 85 received antibiotics and 274 did not. The baseline characteristics were similar between the groups, except for gestational age at the time of delivery (39.2 weeks vs 39.5 weeks for the antibiotic and no antibiotic groups, respectively; P=.02). The incidence in postpartum fever showed a downward trend in the antibiotic group (10.59% for the antibiotic group vs 18.98% for the no antibiotic group; P=.07). Significantly fewer women in the antibiotic group were treated for postpartum endometritis (3.53% vs 11.31%; P=.03). Neonatal intensive care unit admission and neonatal antibiotic administration rates were higher in the antibiotic group (41.18% vs 17.88%; P<.001 and 36.47% vs 12.41%; P<.001, respectively). The incidence of 5-minute Apgar score of <7 was higher in the antibiotic group (8.25% vs 2.19%; P=.016). After controlling for age, gestational age, body mass index, group B streptococci status, delivery method, parity, administration of epidural, and receipt of acetaminophen, the odds for postpartum fever were reduced by a factor of 0.42 (95% confidence interval, 0.18-0.99) among women who received antibiotics when compared with those who did not receive antibiotics. Outcome results are presented in Table 2.

CONCLUSION

Although there was a lower rate of treatment for endometritis among women who received antibiotics for a single isolated maternal fever, there was a higher rate of neonatal intensive care unit admissions and 5-minute Apgar score of <7. This indicates that there likely is maternal benefit associated with antibiotic use, however, there are concerns about the neonatal risk.

Intrapartum and Postpartum Management of Intra-amniotic Infection

Importance

Intra-amniotic infection (IAI) is a common condition with potentially devastating maternal and neonatal complications. However, there are incomplete data regarding the most effective antimicrobial treatment regimen for this condition.

Objective

This article aims to review the current evidence and recommendations for intrapartum and postpartum management of IAI.

Evidence Acquisition

Original research articles, review articles, and guidelines on IAI were reviewed.

Results

Numerous known risk factors for IAI exist, some of which are modifiable. Serious neonatal complications can result from exposure to IAI including increased risk of preterm birth and neonatal death. Possible maternal complications include increased risk of cesarean delivery, postpartum hemorrhage, and postpartum endometritis. Antibiotics are the mainstay of treatment for IAI for both mothers and neonates, although there is no consensus on which antimicrobial agents are best and the appropriate duration of therapy.

Conclusions and Relevance

Monitoring patients for signs of IAI, proper treatment, and communication of the diagnosis with the pediatric team are essential for preventing maternal and neonatal complications of IAI. More research is needed to determine the proper treatment regimens for both mothers diagnosed with IAI and their neonates.

Is Group B Streptococcus Colonization Associated with Maternal Peripartum Infection in an Era of Routine Prophylaxis?

OBJECTIVE

This study aimed to assess whether colonization with group B streptococcus (GBS) is associated with maternal peripartum infection in an era of routine prophylaxis.

STUDY DESIGN

This study presented a secondary analysis of women delivering ≥37 weeks who underwent a trial of labor from the U.S. Consortium on Safe Labor (CSL) study. The exposure was maternal GBS colonization and the outcome was a diagnosis of chorioamnionitis, and secondarily, analyses were restricted to deliveries not admitted in labor and measures of postpartum infection (postpartum fever, endometritis, and surgical site infection). Logistic regression with generalized estimating equations was used accounting for within-woman correlations. Models adjusted for maternal age, parity, race, prepregnancy body mass index, pregestational diabetes, insurance status, study site/region, year of delivery, number of vaginal exams from admission to delivery, and time (in hours) from admission to delivery.

RESULTS

Among 170,804 assessed women, 33,877 (19.8%) were colonized with GBS and 5,172 (3.0%) were diagnosed with chorioamnionitis. While the frequency of GBS colonization did not vary by chorioamnionitis status (3.0% in both groups), in multivariable analyses, GBS colonization was associated with slightly lower odds of chorioamnionitis (adjusted odds ratio [AOR]: 0.89; 95% confidence interval [CI]: 0.83-0.96). In secondary analyses, this association held regardless of spontaneous labor on admission; and the odds of postpartum infectious outcomes were not higher with GBS colonization.

CONCLUSION

In contrast to historical data, GBS colonization was associated with lower odds of chorioamnionitis in an era of routine GBS screening and prophylaxis.

KEY POINTS

· Data in an era prior to routine group B streptococcus (GBS) screening and prophylaxis showed that maternal GBS colonization was associated with a higher frequency of maternal peripartum infection.. · In the current study, GBS colonization was associated with lower odds of chorioamnionitis in an era of routine GBS screening and prophylaxis.. · The results highlight potential benefits of GBS screening and intrapartum antibiotic prophylaxis beyond neonatal disease prevention, including mitigating the risk of maternal infectious morbidity..

Chorioamnionitis and Risk for Maternal and Neonatal Sepsis: A Systematic Review and Meta-analysis

OBJECTIVE

To estimate the risk of maternal and neonatal sepsis associated with chorioamnionitis.

DATA SOURCES

PubMed, BIOSIS, and ClinicalTrials.gov databases were systematically searched for full-text articles in English from inception until May 11, 2020.

METHODS OF STUDY SELECTION

We screened 1,251 studies. Randomized controlled trials, case-control, or cohort studies quantifying a relationship between chorioamnionitis and sepsis in mothers (postpartum) or neonates born at greater than 22 weeks of gestation were eligible. Studies were grouped for meta-analyses according to exposures of histologic or clinical chorioamnionitis and outcomes of maternal or neonatal sepsis.

TABULATION, INTEGRATION, AND RESULTS

One hundred three studies were included, and 55 met criteria for meta-analysis (39 studies of preterm neonates, 10 studies of general populations of preterm and term neonates, and six studies of late preterm and term neonates). Study details and quantitative data were abstracted. Random-effects models were used to generate pooled odds ratios (ORs); most studies only reported unadjusted results. Histologic chorioamnionitis was associated with confirmed and any early-onset neonatal sepsis (unadjusted pooled ORs 4.42 [95% CI 2.68-7.29] and 5.88 [95% CI 3.68-9.41], respectively). Clinical chorioamnionitis was also associated with confirmed and any early-onset neonatal sepsis (unadjusted pooled ORs 6.82 [95% CI 4.93-9.45] and 3.90 [95% CI 2.74-5.55], respectively). Additionally, histologic and clinical chorioamnionitis were each associated with higher odds of late-onset sepsis in preterm neonates. Confirmed sepsis incidence was 7% (early-onset) and 22% (late-onset) for histologic and 6% (early-onset) and 26% (late-onset) for clinical chorioamnionitis-exposed neonates. Three studies evaluated chorioamnionitis and maternal sepsis and were inconclusive.

CONCLUSION

Both histologic and clinical chorioamnionitis were associated with early- and late-onset sepsis in neonates. Overall, our findings support current guidelines for preventative neonatal care. There was insufficient evidence to determine the association between chorioamnionitis and maternal sepsis.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42020156812.

Factors associated with extubation failure in very low birth weight infants: a cohort study in the northeast Brazil

OBJECTIVES

Identifying and understanding the main risk factors associated with extubation failure of very low birthweight (VLBW) infants in different populations can subsequently help in establishing better criteria while taking decision of extubation. The aim of the study was to identify factors associated with extubation failure in VLBW infants.

METHODS

A cohort study of VLBW infants who underwent their first extubation between April 2018 and December 2019 in a Neonatal Intensive Care Unit, Alagoas, Brazil, were included in this study. Extubation failure was defined as reintubation within seven days of extubation. Relative risks of predictive variables different between the extubation success group (ES) and extubation failure group (EF) were estimated with a robust Poisson regression model.

RESULTS

Out of the 112 infants included, 26 (23%) cases exhibited extubation failure. Extremely low birth weight (RR 2.55, 95% CI 1.07, 6.06), mechanical ventilation duration for first extubation greater than seven days (RR 2.66, 95% CI 1.10, 6.45), vaginal delivery (RR 2.07, 95% CI 1.03, 4.18) and maternal chorioamnionitis (RR 4.89, 95% CI 1.26-18.98) remained independently associated with extubation failure. EF had a significant greater need for respiratory support, longer oxygen therapy duration, more bronchopulmonary dysplasia (BPD) and longer length of hospital stay, even when adjusted for confounding variables.

CONCLUSIONS

Extremely low birth weight infants needing mechanical ventilation, wherein the duration for first extubation was longer than seven days, with vaginal delivery and maternal chorioamnionitis failed more frequently at the first attempt of extubation. And this failure increased the risk of BPD and the length of hospital stay.

Cesarean delivery at term for non-reassuring fetal heart rate tracing: risk factors and predictability

OBJECTIVE

To delineate risk factors for adverse outcomes among those who underwent cesarean delivery (CD) for non-reassuring fetal heart rate tracing (NRFHT) and ascertain whether neonatal or maternal morbidity can be predicted accurately.

METHODS

The Consortium on Safe Labor Database was utilized for this secondary analysis. Inclusion criteria were non-anomalous, singleton gestations between 37.0 and 41.6 weeks who underwent CD for NRFHT. Composite adverse neonatal outcomes (CANO) included Apgar <5 at 5 min, seizures, mechanical ventilation, sepsis, intraventricular hemorrhage, necrotizing enterocolitis or neonatal death. Composite adverse maternal outcomes (CAMO) included endometritis, blood transfusion, wound complication, admission to intensive care unit, thromboembolism, hysterectomy or death. Bivariable analysis and multivariable Poisson regression were used to identify risk factors independently associated with adverse outcomes. Receiver operating characteristic (ROC) curves were created to evaluate the predictive value of the models for adverse outcomes.

RESULTS

Of 228,438 births in the database, 7310 individuals (3.7%) met inclusion criteria. Among this cohort, CANO occurred 3.8% of the time. CANO was less common among people over 35 years (9.8% versus 18.4% p < .01) but was more common among those with at least high-school education (15.3% versus 11.2%; p < .01), varying by ethnicity (p < .01). CAMO occurred in 3.4% and was less common among those undergoing induction of labor (37.3% versus 49.4%; p < .01) and more common among those with clinical chorioamnionitis (8.4% versus 4.3%; p < .01). The area under the curve (AUC) for ROC curve to identify CANO was 0.63 implying a limited ability to predict neonatal adverse outcomes. The AUC for identifying women with maternal adverse outcomes was 0.69 also indicating a moderate prediction ability.

CONCLUSIONS

Among singletons between 37 and 41 weeks who labored, the rate of CD for NRFHT was about 3.7% and among them CANO occurred in 3.8%. While risk factors for adverse neonatal outcomes following CD for NRFHT are identifiable, they do not suffice to predict them.

Circulating angiogenic profiles and histo-morphological placental characteristics of uncomplicated post-date pregnancies

INTRODUCTION

The objectives of this study were to describe the histo-morphology of post-date placentas in clinically uncomplicated pregnancies without adverse delivery outcomes and the association with maternal circulating pre-delivery Placental Growth Factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1), as well as the sFlt-1/PlGF ratio.

METHODS

Post-date placentas (gestational week ≥40⁺², n = 87) were macroscopically and histo-morphologically assessed according to the international, standardized Amsterdam Workshop Consensus Group criteria. Inter-rater agreement was evaluated by percentage of agreement. PlGF and sFlt-1 concentrations were available from maternal serum sampled close to delivery, and were compared by Mann-Whitney U test. Linear regression analyses were adjusted for predefined potential confounders.

RESULTS

The majority of the post-date placentas showed morphological signs of delayed maturation. About half of the placentas showed increased syncytial knotting and fibrin. In placentas with increased presence of intervillous fibrin, median maternal PlGF level was significantly lower (p = 0.004), median sFlt-1 level higher and sFlt-1/PlGF ratio significantly higher (p = 0.002) compared to those with normal fibrin amounts. Increased placental syncytial knotting was associated with lower levels of PlGF, higher sFlt-1 and higher sFlt-1/PlGF ratio compared to those with normal knotting.

DISCUSSION

Our standardized morphological study of post-date placentas in clinically healthy women with uncomplicated pregnancies and delivery outcomes revealed delayed maturation in the majority of placentas. Increased pre-delivery circulating anti-angiogenic profile was associated with increased intervillous fibrin and syncytial knotting. We propose that circulating maternal angiogenic biomarkers may be of future use in clinical post-date pregnancy assessment, as they reflect important aspects of placental health and function.

Sneathia: an emerging pathogen in female reproductive disease and adverse perinatal outcomes

Sneathia is an emerging pathogen implicated in adverse reproductive and perinatal outcomes. Although scarce, recent data suggest that vaginally residing Sneathia becomes pathogenic following its ascension into the upper urogenital tract, amniotic fluid, placenta, and foetal membranes. The role of Sneathia in women's health and disease is generally underappreciated because the cultivation of these bacteria is limited by their complex nutritional requirements, slow growth patterns, and anaerobic nature. For this reason, molecular methods are typically required for the detection and differential diagnosis of Sneathia infections. Here, we review the laboratory methods used for the diagnosis of Sneathia infections, the molecular mechanisms underlying its virulence, and its sensitivity to antibiotics. We further review the evidence of Sneathia's contributions to the pathogenesis of bacterial vaginosis, chorioamnionitis, preterm prelabour rupture of membranes, spontaneous preterm labour, stillbirth, maternal and neonatal sepsis, HIV infection, and cervical cancer. Collectively, growing evidence indicates that Sneathia represents an important yet underappreciated pathogen affecting the development and progression of several adverse clinical conditions diagnosed in pregnant women and their neonates, as well as in non-pregnant women.

Clinical chorioamnionitis at term X: microbiology, clinical signs, placental pathology, and neonatal bacteremia - implications for clinical care

OBJECTIVES

Clinical chorioamnionitis at term is considered the most common infection-related diagnosis in labor and delivery units worldwide. The syndrome affects 5-12% of all term pregnancies and is a leading cause of maternal morbidity and mortality as well as neonatal death and sepsis. The objectives of this study were to determine the (1) amniotic fluid microbiology using cultivation and molecular microbiologic techniques; (2) diagnostic accuracy of the clinical criteria used to identify patients with intra-amniotic infection; (3) relationship between acute inflammatory lesions of the placenta (maternal and fetal inflammatory responses) and amniotic fluid microbiology and inflammatory markers; and (4) frequency of neonatal bacteremia.

METHODS

This retrospective cross-sectional study included 43 women with the diagnosis of clinical chorioamnionitis at term. The presence of microorganisms in the amniotic cavity was determined through the analysis of amniotic fluid samples by cultivation for aerobes, anaerobes, and genital mycoplasmas. A broad-range polymerase chain reaction coupled with electrospray ionization mass spectrometry was also used to detect bacteria, select viruses, and fungi. Intra-amniotic inflammation was defined as an elevated amniotic fluid interleukin-6 (IL-6) concentration ≥2.6 ng/mL.

RESULTS

(1) Intra-amniotic infection (defined as the combination of microorganisms detected in amniotic fluid and an elevated IL-6 concentration) was present in 63% (27/43) of cases; (2) the most common microorganisms found in the amniotic fluid samples were Ureaplasma species, followed by Gardnerella vaginalis; (3) sterile intra-amniotic inflammation (elevated IL-6 in amniotic fluid but without detectable microorganisms) was present in 5% (2/43) of cases; (4) 26% of patients with the diagnosis of clinical chorioamnionitis had no evidence of intra-amniotic infection or intra-amniotic inflammation; (5) intra-amniotic infection was more common when the membranes were ruptured than when they were intact (78% [21/27] vs. 38% [6/16]; p=0.01); (6) the traditional criteria for the diagnosis of clinical chorioamnionitis had poor diagnostic performance in identifying proven intra-amniotic infection (overall accuracy, 40-58%); (7) neonatal bacteremia was diagnosed in 4.9% (2/41) of cases; and (8) a fetal inflammatory response defined as the presence of severe acute funisitis was observed in 33% (9/27) of cases.

CONCLUSIONS

Clinical chorioamnionitis at term, a syndrome that can result from intra-amniotic infection, was diagnosed in approximately 63% of cases and sterile intra-amniotic inflammation in 5% of cases. However, a substantial number of patients had no evidence of intra-amniotic infection or intra-amniotic inflammation. Evidence of the fetal inflammatory response syndrome was frequently present, but microorganisms were detected in only 4.9% of cases based on cultures of aerobic and anaerobic bacteria in neonatal blood.

Maternal proximity to petrochemical industrial parks and risk of premature rupture of membranes

BACKGROUND

Living near petrochemical industries has been reported to increase the risks of adverse birth outcomes, such as low birth weight and preterm delivery. However, evidence regarding the role of petrochemical exposure in pregnancy complications remains limited. This study evaluated the association between maternal proximity to petrochemical industrial parks (PIPs) during pregnancy and the occurrence of premature rupture of membranes (PROM).

METHODS

We performed a population-based 1:3 case-control study by using the 2004-2014 Taiwanese Birth Certificate Database. Birth records reported as stillbirth or bearing congenital anomalies were excluded. Cases were newborns reported to have PROM, whereas controls were randomly sampled from those without any pregnancy complications by matching birth year and urbanization index of the residential township. The proximity to PIPs was evaluated by calculating the distance to the nearest PIP of the maternal residential township during pregnancy. Furthermore, petrochemical exposure opportunity, accounting for monthly prevailing wind direction, was quantified during the entire gestational period. We applied conditional logistic regression models to evaluate the associations.

RESULTS

In total, 29371 PROM cases were reported during the study period, with a corresponding 88113 healthy controls sampled. The results revealed that living within a 3-km radius of PIPs during pregnancy would increase the risk of PROM (odds ratio [OR] = 1.76, 95% CI: 1.66-1.87). Furthermore, compared with the lowest exposed group, those with high petrochemical exposure opportunity had a significantly increased risk of PROM occurrence (OR = 1.69-1.75). The adverse effects remained robust in the subgroup analysis for both term- and preterm-PROM.

CONCLUSIONS

The results of the present work provide evidence that living near PIPs during pregnancy would increase the risk of PROM, and additional studies are warranted to confirm our findings.

Chorioamnionitis and adverse outcomes in low-risk pregnancies: a population-based study

OBJECTIVE

To compare the composite neonatal and maternal adverse outcomes among low-risk pregnancies with versus without chorioamnionitis.

METHODS

We conducted a retrospective cohort study using U.S. Vital Statistics Data. The study population was restricted to full term, low-risk, singleton pregnancies. Pregnancies were categorized into those affected and unaffected by chorioamnionitis. The primary outcome was composite neonatal adverse outcome and the secondary outcome was composite maternal adverse outcome. Multivariable Poisson regression models with robust error variance were used to examine the factors associated with chorioamnionitis and to evaluate the association between chorioamnionitis and adverse outcomes [using adjusted relative risk (aRR) and 95% confidence interval (CI)].

RESULTS

Of 19.7 million live births, 59.4% met inclusion criteria; among them, 1.7% were complicated by chorioamnionitis. The risk of composite neonatal adverse outcome was higher in newborns delivered by women with chorioamnionitis (aRR = 3.40; 95% CI = 3.30-3.49). Compared to women without chorioamnionitis, those with chorioamnionitis had a higher risk of composite maternal adverse outcome (aRR = 2.42; 95% CI = 2.31-2.55). Infant mortality was also higher in affected pregnancies (aRR = 1.23; 95% CI = 1.09-1.38).

CONCLUSION

Among low-risk pregnancies, chorioamnionitis is associated with a higher risk of composite neonatal and maternal adverse outcomes. Infant death is also increased.

Intraamniotic Infection Rates after Intrauterine Pressure Catheter with and without Amnioinfusion

OBJECTIVE

This study aimed to examine the rates of intraamniotic infection between intrauterine pressure catheter with amnioinfusion and intrauterine pressure catheter alone.

STUDY DESIGN

This was a retrospective cohort study of all women who had an intrauterine pressure catheter placement during labor at a tertiary referral hospital from January 2016 to June 2018. Outcomes were compared between women who had an intrauterine pressure catheter with amnioinfusion and intrauterine pressure catheter placement alone. The primary outcome was the rate of intraamniotic infection. Secondary outcomes included postpartum endometritis, postpartum hemorrhage (blood loss of ≥1,000 mL), quantitative blood loss (mL), and cesarean delivery. Multivariable logistic regression analysis was performed to calculate adjusted odds ratios (aOR) and 95% confidence interval (95% CI), controlling for age, race, body mass index, gestational age, and length of time of rupture of membranes.

RESULTS

Of 1,268 women with an intrauterine pressure catheter, 298 (23.5%) also had an amnioinfusion. Women who had amnioinfusion through an intrauterine pressure catheter compared with those who had intrauterine pressure catheter alone had similar rates of intraamniotic infection (5.4 vs. 8.0%, crude p = 0.12, aOR 0.69; 95% CI 0.39-1.21), as well as secondary outcomes such as postpartum endometritis (3.0 vs. 2.5%, crude p = 0.61, aOR 1.12; 95% CI 0.49-2.53), postpartum hemorrhage (16.1 vs. 15.8%, crude p = 0.89, aOR 1.07; 95% CI 0.75-1.54), blood loss (479.5 vs. 500 mL, adjusted p = 0.89), and cesarean delivery (40.6 vs. 43.1%, crude p = 0.45, aOR 0.90; 95% CI 0.68-1.19).

CONCLUSION

Amnioinfusion was not associated with increased odds of intraamniotic infection compared with intrauterine pressure catheter placement alone.

KEY POINTS

· Amnioinfusion involves instilling fluid into the amniotic cavity to relieve variable decelerations.. · Amnioinfusion is not associated with increased odds of chorioamnionitis compared to IUPC alone.. · Amnioinfusion is not associated with increased odds of PPH compared to IUPC placement alone..

Determining the optimal antibiotic regimen for chorioamnionitis: A systematic review and meta-analysis

INTRODUCTION

To evaluate the effect of antibiotic regimens for chorioamnionitis on maternal and neonatal outcomes.

MATERIAL AND METHODS

We conducted a systematic review, wherein we searched six bibliographic databases until June 2020 and included randomized clinical trials describing antibiotic regimens for treating chorioamnionitis. Risk of bias was assessed using the Cochrane Risk of Bias tool V2.0. Random-effects meta-analysis was performed and results were presented as risk ratio (RR) and mean differences (MD) with 95% CI.

RESULTS

Fourteen trials at low-to-high risk of bias were included. Three trials (n = 244), comparing different intrapartum antibiotic regimens, showed no difference in outcomes except for lower composite maternal morbidity (endometritis, pneumonia, sepsis, blood transfusion, and ileus) with ampicillin/sulbactam vs ampicillin/gentamicin in one study (0/43 vs 6/49, P = .03). Three trials (n = 295) comparing different doses of intrapartum antibiotics showed no differences in maternal and neonatal outcomes, although one study showed a shorter duration of antibiotic treatment in the experimental arm (4 mg/kg gentamicin q24h + 1200 mg clindamycin q12h) vs conventional arm (1.33 mg/kg gentamicin + 800 mg clindamycin q8h) (48.0 ± 36 hours vs 55.2 ± 48 hours, P = .04). Four trials (n = 484) comparing postpartum antibiotics vs no antibiotics showed no difference in outcomes except for a shorter hospital stay (two studies, MD -7.90 hours, 95% CI -13.52 to -2.27 hours). Three trials (n = 447) comparing single vs multiple doses of postpartum antibiotics showed shorter hospital stay [MD -19.14 hours, 95% CI -29.88 to -8.41 hours), but no differences in treatment failure (RR 1.73, 95% CI 0.69-4.30) or total antibiotic dose (MD -9.24, 95% CI -19.49 to 1.01). One trial (n = 48) comparing intrapartum vs postpartum initiation of treatment found benefits to intrapartum (vs postpartum) initiation of antibiotics, in terms of postpartum maternal hospital stay (MD -24 hours, 95% CI -45.56 to -1.44 hours), neonatal hospital stay (MD -45.6 hours, -93.84 to -11.76 hours), and neonatal pneumonia or sepsis (RR 0.06, 95% CI 0.00-0.95).

CONCLUSIONS

Upon diagnosis of chorioamnionitis, there is limited evidence to recommend the prompt initiation of intrapartum antibiotics, and to consider a single dose of postpartum antibiotics over multiple doses or no treatment. Well-designed trials using standard definitions of chorioamnionitis, outcome measures, and newer antibiotics are required to inform clinical practice with regard to the preferred antibiotic regimen, dose, and duration to optimize maternal and neonatal outcomes.

Prediction of adverse neonatal outcome among newborns born through meconium-stained amniotic fluid

OBJECTIVE

To study maternal and intrapartum factors associated with adverse neonatal outcome in deliveries complicated by meconium-stained amniotic fluid (MSAF).

METHODS

A retrospective cohort study of all women with singleton gestations undergoing trial of labor with MSAF during 2011-2020. Deliveries with adverse neonatal outcome were compared with deliveries without.

RESULTS

Overall, 11 329 were included; 376 (3.3%) neonates were diagnosed with adverse neonatal outcomes. Multivariable regression analysis underlined the following factors as independently associated with composite adverse neonatal outcome: pregestational diabetes (odds ratio [OR] 3.21, 95% confidence interval [CI] 1.09-9.43, P = 0.031), polyhydramnios (OR 2.14, 95% CI 1.33-3.44, P = 0.002), fever (OR 2.52, 95% CI 1.67-3.80, P < 0.001), and amnioinfusion (OR 1.73, 95% CI 1.24-2.2438, P = 0.003). When 0, 1, 2, and 3 of the independent risk factors identified were present, the rates of adverse neonatal outcome were 2.9%, 5.5%, 10.0%, and 100%, respectively.

CONCLUSION

The current study's results suggest that special attention should be payed to deliveries complicated by MSAF and with any of the following factors-polyhydramnios, intrapartum fever, amnioinfusion, and pregestational diabetes.

Spontaneous Broad Ligament Hematoma after Vaginal Delivery Requiring Hysterectomy

Background  Broad ligament hematomas are rare in the setting of vaginal delivery. When they do occur, patients typically present with acute hemodynamic instability. No cases of infected broad ligament hematomas have been reported. Case  A 22-year-old G2 P1011 status post vaginal delivery complicated by chorioamnionitis and pre-eclampsia presented 5 days postpartum with subjective complaints of fever, vomiting, and increased vaginal bleeding. She was treated with antibiotics and uterine evacuation was planned for presumed retained products. After dilation and curettage, the patient was transferred to our facility, as her clinical status did not improve, and was later found to have an infected broad ligament hematoma requiring hysterectomy. Conclusion  Though uncommon, broad ligament hematomas should be considered in postpartum women presenting with anemia and vaginal bleeding, even without hemodynamic instability. Recent intrauterine infections may predispose to hematoma infection.

Management of clinical chorioamnionitis: an evidence-based approach

This review aimed to examine the existing evidence about interventions proposed for the treatment of clinical chorioamnionitis, with the goal of developing an evidence-based contemporary approach for the management of this condition. Most trials that assessed the use of antibiotics in clinical chorioamnionitis included patients with a gestational age of ≥34 weeks and in labor. The first-line antimicrobial regimen for the treatment of clinical chorioamnionitis is ampicillin combined with gentamicin, which should be initiated during the intrapartum period. In the event of a cesarean delivery, patients should receive clindamycin at the time of umbilical cord clamping. The administration of additional antibiotic therapy does not appear to be necessary after vaginal or cesarean delivery. However, if postdelivery antibiotics are prescribed, there is support for the administration of an additional dose. Patients can receive antipyretic agents, mainly acetaminophen, even though there is no clear evidence of their benefits. Current evidence suggests that the administration of antenatal corticosteroids for fetal lung maturation and of magnesium sulfate for fetal neuroprotection to patients with clinical chorioamnionitis between 24 0/7 and 33 6/7 weeks of gestation, and possibly between 23 0/7 and 23 6/7 weeks of gestation, has an overall beneficial effect on the infant. However, delivery should not be delayed to complete the full course of corticosteroids and magnesium sulfate. Once the diagnosis of clinical chorioamnionitis has been established, delivery should be considered, regardless of the gestational age. Vaginal delivery is the safer option and cesarean delivery should be reserved for standard obstetrical indications. The time interval between the diagnosis of clinical chorioamnionitis and delivery is not related to most adverse maternal and neonatal outcomes. Patients may require a higher dose of oxytocin to achieve adequate uterine activity or greater uterine activity to effect a given change in cervical dilation. The benefit of using continuous electronic fetal heart rate monitoring in these patients is unclear. We identified the following promising interventions for the management of clinical chorioamnionitis: (1) an antibiotic regimen including ceftriaxone, clarithromycin, and metronidazole that provides coverage against the most commonly identified microorganisms in patients with clinical chorioamnionitis; (2) vaginal cleansing with antiseptic solutions before cesarean delivery with the aim of decreasing the risk of endometritis and, possibly, postoperative wound infection; and (3) antenatal administration of N-acetylcysteine, an antioxidant and antiinflammatory agent, to reduce neonatal morbidity and mortality. Well-powered randomized controlled trials are needed to assess these interventions in patients with clinical chorioamnionitis.

Epidural analgesia, intrapartum hyperthermia, and neonatal brain injury: a systematic review and meta-analysis

BACKGROUND

Epidural analgesia is associated with intrapartum hyperthermia, and chorioamnionitis is associated with neonatal brain injury. However, it is not known if epidural hyperthermia is associated with neonatal brain injury. This systematic review and meta-analysis investigated three questions: (1) does epidural analgesia cause intrapartum hyperthermia, (2) is intrapartum hyperthermia associated with neonatal brain injury, and (3) is epidural-induced hyperthermia associated with neonatal brain injury?

METHODS

PubMed, ISI Web of Knowledge, The Cochrane Library, and Embase were searched from inception to January 2020 using Medical Subject Headings (MeSH) terms relating to epidural analgesia, hyperthermia, labour, and neonatal brain injury. Studies were reviewed independently for inclusion and quality by two authors (Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach). Two meta-analyses were performed using the Mantel-Haenszel fixed effect method to generate odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Forty-one studies were included for Question 1 (646 296 participants), 36 for Question 2 (11 866 021 participants), and two studies for Question 3 (297 113 participants). When the mode of analgesia was randomised, epidural analgesia was associated with intrapartum hyperthermia (OR: 4.21; 95% CI: 3.48-5.09). There was an association between intrapartum hyperthermia and neonatal brain injury (OR: 2.79; 95% CI: 2.54-2.3.06). It was not possible to quantify the association between epidural-induced hyperthermia and neonatal brain injury.

CONCLUSIONS

Epidural analgesia is a cause of intrapartum hyperthermia, and intrapartum hyperthermia of any cause is associated with neonatal brain injury. Further work is required to establish if epidural-induced hyperthermia is a cause of neonatal brain injury.

RNA Sequencing Reveals Diverse Functions of Amniotic Fluid Neutrophils and Monocytes/Macrophages in Intra-Amniotic Infection

Intra-amniotic infection, the invasion of microbes into the amniotic cavity resulting in inflammation, is a clinical condition that can lead to adverse pregnancy outcomes for the mother and fetus as well as severe long-term neonatal morbidities. Despite much research focused on the consequences of intra-amniotic infection, there remains little knowledge about the innate immune cells that respond to invading microbes. We performed RNA-seq of sorted amniotic fluid neutrophils and monocytes/macrophages from women with intra-amniotic infection to determine the transcriptomic differences between these innate immune cells. Further, we sought to identify specific transcriptomic pathways that were significantly altered by the maternal or fetal origin of amniotic fluid neutrophils and monocytes/macrophages, the presence of a severe fetal inflammatory response, and pregnancy outcome (i.e., preterm or term delivery). We show that significant transcriptomic differences exist between amniotic fluid neutrophils and monocytes/macrophages from women with intra-amniotic infection, indicating the distinct roles these cells play. The transcriptome of amniotic fluid immune cells varies based on their maternal or fetal origin, and the significant transcriptomic differences between fetal and maternal monocytes/macrophages imply that those of fetal origin exhibit impaired functions. Notably, transcriptomic changes in amniotic fluid monocytes/macrophages suggest that these immune cells collaborate with neutrophils in the trafficking of fetal leukocytes throughout the umbilical cord (i.e., funisitis). Finally, amniotic fluid neutrophils and monocytes/macrophages from preterm deliveries display enhanced transcriptional activity compared to those from term deliveries, highlighting the protective role of these cells during this vulnerable period. Collectively, these findings demonstrate the underlying complexity of local innate immune responses in women with intra-amniotic infection and provide new insights into the functions of neutrophils and monocytes/macrophages in the amniotic cavity.

Chorioamnionitis at latent phase more than doubles the risk for cesarean delivery compared to chorioamnionitis at active phase

PURPOSE

Chorioamnionitis, or intraamniotic infection, is a common condition, carrying an increased risk of intrapartum cesarean delivery (CD). The morbidity related to chorioamnionitis is more common in those undergoing CD, as compared to those with successful vaginal delivery. We aimed to examine the risk factors associated with CD among women with chorioamnionitis.

METHODS

A retrospective cohort study from a tertiary medical center. We included women at term carrying a singleton gestation with suspected chorioamnionitis undergoing a trial of labor between 2011 and 2019. The primary outcome was the mode of delivery.

RESULTS

Data from 1436 women with chorioamnionitis were analyzed; 1288 (89.7%) were nulliparous. Overall, 1064 (74.1%) delivered vaginally, and 372 (25.9%) by CD. The rate of CD was significantly higher in nulliparous as compared to parous parturients (26.9% vs. 16.9%, P = 0.008), and in those with fever onset at latent phase as compared to those in whom fever appeared at active labor (≥ 6 cm) (47.0% vs. 18.1%, P < 0.001). In a multivariate analysis, CD was positively associated with: onset of fever at latent phase (aOR [95% CI] 4.75 (3.54, 6.32), P < 0.001), nulliparity (aOR [95% CI] 3.25 (1.98, 5.34), P < 0.001), maternal age (aOR [95% CI] 1.52 (1.10, 2.09), P = 0.01) and birth weight (aOR [95% CI] 1.23 (1.04, 1.44), P = 0.01).

CONCLUSION

Women with chorioamnionitis had a high rate of CD. Nulliparity and onset of fever prior to active labor were the strongest independent predictors of CD. It remains to be determined whether those deemed at high risk for failed trial of labor, should undergo CD earlier in the course of labor to improve chorioamnionitis-related outcomes.

Is it safe to perform amnioinfusion in the presence of suspected intraamniotic infection?

OBJECTIVE

To study the effect of amnioinfusion in the presence of suspected intra-amniotic infections (SII) on maternal outcomes among women delivering at term.

METHODS

A retrospective cohort study was conducted at a tertiary medical center. All consecutive singleton term deliveries with SII during 2011-2019 were included. Cases where amnioinfusion was performed after the diagnosis of SII were compared to cases without amnioinfusion, matched by cervical dilation at diagnosis of SII. Maternal and obstetric adverse outcomes were compared.

RESULTS

After matching for cervical dilation at diagnosis of SII, the study cohort included 786 women: 62 (7.9%) women in the amnioinfusion group and 724 (92.1%) in the control group. A composite of adverse maternal outcomes occurred in 106 (13.5%) deliveries. There were no significant differences in the rates of maternal adverse outcomes between the amnioinfusion and control groups (11.0% vs 13.7%, respectively; P=0.59), including postpartum endometritis (5.0% vs 3.3%, respectively; P=0.46) and febrile morbidity (10.0% vs 6.5%, respectively; P=0.42). Neonatal blood gas outcomes and Apgar scores did not differ between groups.

CONCLUSION

The use of amnioinfusion for alleviating non-reassuring fetal heart rate in the presence of SII is safe and does not increase the rate of maternal adverse outcome.

Determinants of adverse neonatal outcome in vaginal deliveries complicated by suspected intraamniotic infection

PURPOSE

Intraamniotic infection, categorized into isolated maternal fever, suspected intraamniotic infection (SII), and confirmed intraamniotic infection, is associated with neonatal morbidity. However, there is paucity of data regarding the association between intraamniotic infection duration and neonatal outcomes among term singleton vaginal deliveries. We aimed to study the risk factors for adverse neonatal outcome among vaginal deliveries complicated by SII.

METHODS

A retrospective observational study conducted at a tertiary medical center. All consecutive singleton term deliveries with SII were included between 2011 and 2019. Maternal and obstetrical characteristics were evaluated to identify risk factors for adverse neonatal outcome. Correlation between SII duration and neonatal adverse outcome was analyzed.

RESULTS

Overall, 882 were analyzed. Most women (85.4%) were primiparous. Median gestation age at delivery was 40 ^2/7 weeks. Median time from SII to delivery was 170 min. Adverse neonatal outcomes occurred in 113 (12.8%) of deliveries. Duration of SII was not associated with adverse neonatal outcome. Analysis for determinants of adverse neonatal outcome revealed that oligohydramnios was more common in pregnancies with adverse neonatal outcome (7/113 (6.2%) vs. 41 (5.4%) OR [95% CI] 2.47 (1.02-5.98), p = 0.03). Duration of second stage of labor was longer in the adverse outcome group (median 179 min vs. 126 min, p = 0.008). Prolonged second stage was more common in the adverse outcome group (60 (53.1%) vs. 273 (35.5%) OR [95% CI] 2.05 (1.38-3.06), p < 0.001). On logistic regression analysis, prolonged second stage was the only modifiable factor independently associated with adverse neonatal outcome [adjusted OR 2.09 (1.37-3.2), p = 0.001]. Other variables tested did not differ between groups. Only phototherapy and base excess ≥ 12 mmol/L were significantly associated with the duration of second stage of labor; for each additional hour of the second stage, the OR for the former increased by 0.34 (p = 0.008), and for the latter by 0.69 (p = 0.007).

CONCLUSION

Duration of suspected intraamniotic infection was not associated with increased neonatal morbidity among women delivering vaginally at term. Prolonged second stage was a strong independent predictor of an adverse neonatal outcome among fetuses exposed to intraamniotic infection.

Chorioamnionitis versus intraamniotic infection among preterm deliveries-is postpartum infectious morbidity different?

BACKGROUND

Chorioamnionitis can have a highly variable definition with substantial maternal and fetal morbidity, with higher frequencies in preterm births. With the recently updated intraamniotic infection diagnostic criteria by the American College of Obstetricians and Gynecologists, fewer women experiencing preterm delivery may qualify for intrapartum antibiotic treatment, potentially resulting in higher postpartum infectious morbidity.

OBJECTIVE

This study aimed to estimate whether the proportion of women delivering preterm who develop postpartum endometritis differs between subjects diagnosed as having clinical chorioamnionitis and those meeting the American College of Obstetricians and Gynecologists' criteria for intraamniotic infection.

STUDY DESIGN

Secondary analysis was conducted using a randomized controlled trial of antenatal magnesium sulfate for the prevention of cerebral palsy. Subjects were included if they had a clinical diagnosis of chorioamnionitis and maternal temperature of ≥37.8°C and excluded if maternal temperature data were missing. The exposure group included women who met the criteria for intraamniotic infection, defined as a single maternal temperature of ≥39.0°C or maternal temperature of 38.0°C to 38.9°C plus 1 additional clinical risk factor (leukocytosis, purulent cervical drainage, or fetal tachycardia). The primary outcome was postpartum endometritis. The odds of postpartum endometritis were compared between women with intraamniotic infection and women with clinical chorioamnionitis, after adjusting for potential confounders using multivariate logistic regression.

RESULTS

Of the original study population, 258 of 2241 (11.8%) subjects met the criteria for chorioamnionitis. Nearly all subjects (98.5%) received antibiotic treatment between randomization and delivery. A total of 144 subjects (55.8%) met the criteria for intraamniotic infection, whereas 114 (44%) only met the criteria for clinical chorioamnionitis. A total of 40 women (15.5%) experienced postpartum endometritis. Women with intraamniotic infection had higher parity (P=.02) and higher maximum maternal temperature (P<.001) and were more likely to have received antibiotic treatment (P=.04). Postpartum endometritis rates were similar between subjects with chorioamnionitis and intraamniotic infection (12% vs 18%; P=.50). After adjustment for potential confounders, the odds of developing postpartum endometritis did not differ between subjects who met the criteria for intraamniotic infection and those who did not (adjusted odds ratio, 1.28; 95% confidence interval, 0.62-2.62).

CONCLUSION

Patients delivering preterm who receive a diagnosis of clinical chorioamnionitis in the intrapartum period seem to have similar odds of developing postpartum endometritis as those meeting the American College of Obstetricians and Gynecologists' criteria for intraamniotic infection, suggesting that this group remains at a high risk for postpartum infectious complications.

Neonatal Seizures Among Low-Risk Pregnancies at Term: Risk Factors and Adverse Outcomes

OBJECTIVE

To examine risk factors and adverse outcomes for neonatal-maternal dyads among low-risk pregnancies at term with subsequent neonatal seizures.

METHODS

United States vital statistics data sets were used for this retrospective study. Inclusion criteria were low-risk women (without hypertensive disease or diabetes) with nonanomalous singleton pregnancies, who delivered after labor at 37-41 weeks of gestation. The primary composite neonatal adverse outcome included 5-minute Apgar score less than 5, assisted ventilation longer than 6 hours, and neonatal death. A secondary outcome was composite maternal adverse outcome. Multivariable Poisson regression models with robust error variance were used, with adjusted relative risk (aRR) and 95% CI reported.

RESULTS

Of 19.76 million live births during the study interval, 11.7 million (59.4%) met inclusion criteria. The rate of neonatal seizures after low-risk pregnancies delivered at term was 0.2 per 1,000 live births. The maternal risks factors associated with neonatal seizures included no prenatal care, smoking during pregnancy, being overweight or obese, and gestational age of 41 weeks. The strongest risk factors for neonatal seizures were chorioamnionitis (relative risk [RR] 5.04, 95% CI 4.40-5.77; aRR 3.27, 95% CI 2.84-3.76) and route of delivery, with operative vaginal (RR 3.62, 95% CI 3.20-4.09; aRR 3.02, 95% CI 2.66-3.43) and cesarean (RR 4.13, 95% CI 3.81-4.48; aRR 3.14, 95% CI 2.86-3.45) higher than spontaneous vaginal. Compared with neonates without seizures, those with seizures had higher risk of composite neonatal adverse outcome (RR 64.55, 95% CI 61.83-67.39; aRR 37.09, 95% CI 35.20-39.08). Compared with women who delivered neonates without seizures, those who delivered neonates with seizures had higher risk of composite maternal adverse outcome (RR 16.27, 95% CI 13.66-19.37; aRR 9.70, 95% CI 8.15-11.53).

CONCLUSION

We identified modifiable maternal risk factors associated with neonatal seizures among low-risk pregnancies at term. Though infrequent, neonatal seizures are associated with higher risk of adverse outcomes in neonatal-maternal dyads.

Detection of microbial cell-free DNA in maternal and umbilical cord plasma in patients with chorioamnionitis using next generation sequencing

Background

Chorioamnionitis has been linked to spontaneous preterm labor and complications such as neonatal sepsis. We hypothesized that microbial cell-free (cf) DNA would be detectable in maternal plasma in patients with chorioamnionitis and could be the basis for a non-invasive method to detect fetal exposure to microorganisms.

Objective

The purpose of this study was to determine whether next generation sequencing could detect microbial cfDNA in maternal plasma in patients with chorioamnionitis.

Study design

Maternal plasma (n = 94) and umbilical cord plasma (n = 120) were collected during delivery at gestational age 28–41 weeks. cfDNA was extracted and sequenced. Umbilical cord plasma samples with evidence of contamination were excluded. The prevalence of microorganisms previously implicated in choriomanionitis, neonatal sepsis and intra-amniotic infections, as described in the literature, were examined to determine if there was enrichment of these microorganisms in this cohort. Specific microbial cfDNA associated with chorioamnionitis was first detected in umbilical cord plasma and confirmed in the matched maternal plasma samples (n = 77 matched pairs) among 14 cases of histologically confirmed chorioamnionitis and one case of clinical chorioamnionitis; 63 paired samples were used as controls. A correlation of rank of a given microorganism across maternal plasma and matched umbilical cord plasma was used to assess whether signals found in umbilical cord plasma were also present in maternal plasma.

Results

Microbial DNA sequences associated with clinical and/or histological chorioamnionitis were enriched in maternal plasma in cases with suspected chorioamnionitis when compared to controls (12/14 microorganisms, p = 0.02). Analysis of the microbial cfDNA in umbilical cord plasma among the 1,251 microorganisms detectable with this assay identified Streptococcus mitis, Ureaplasma spp., and Mycoplasma spp. in cases of suspected chorioamnionitis. This assay also detected cfDNA from Lactobacillus spp. in controls. Comparison between maternal plasma and umbilical cord plasma confirmed these signatures were also present in maternal plasma. Unbiased analysis of microorganisms with significantly correlated signal between matched maternal plasma and umbilical cord plasma identified the above listed 3 microorganisms, all of which have previously been implicated in patients with chorioamnionitis (Mycoplasma hominis p = 0.0001; Ureaplasma parvum p = 0.002; Streptococcus mitis p = 0.007). These data show that the pathogen signal relevant for chorioamnionitis can be identified in both maternal and umbilical cord plasma.

Conclusion

This is the first report showing the detection of relevant microbial cell-free cfDNA in maternal plasma and umbilical cord plasma in patients with clinical and/or histological chorioamnionitis. These results may lead to the development of a specific assay to detect perinatal infections for targeted therapy to reduce early neonatal sepsis complications.

Risk Factors for Postpartum Maternal Infection Following Spontaneous Vaginal Delivery Complicated by Chorioamnionitis

Objective  Guidelines for the management of chorioamnionitis include intrapartum antibiotics, while postpartum antibiotics after spontaneous vaginal delivery (SVD) are reserved high-risk women. Our objective is to describe the incidence of and risk factors for postpartum infection after SVD complicated by chorioamnionitis. Study Design  This is a retrospective study of SVDs with clinically diagnosed chorioamnionitis at a single center. The primary outcome was a composite of postpartum infection. Women who developed the primary outcome were compared with those who did not using bivariate statistics. Regression models were developed to estimate adjusted odds of outcomes. Results  In this cohort, 346 women underwent SVD complicated by chorioamnionitis. Of these, 23 (6.6%) developed postpartum infections (endometritis n  = 7, urinary tract infection/pyelonephritis n  = 6, sepsis n  = 4, and perineal wound infection n  = 6). Receipt of antibiotics intra- or postpartum did not differ between groups, but women with postpartum infections were more likely to deliver prior to 32 weeks (17.4 vs. 4.9%, p  = 0.04). When controlling for antibiotic use, delivery at < 32 weeks was associated with 3.8-fold increased (95% confidence interval: 1.07-13.7) odds of postpartum infection. Conclusion  Postpartum infections occur in ∼1/15 women delivering vaginally with chorioamnionitis, with those who deliver at < 32 weeks' gestation being at increased risk.

Microbial burden and inflammasome activation in amniotic fluid of patients with preterm prelabor rupture of membranes

Background Intra-amniotic inflammation, which is associated with adverse pregnancy outcomes, can occur in the presence or absence of detectable microorganisms, and involves activation of the inflammasome. Intra-amniotic inflammasome activation has been reported in clinical chorioamnionitis at term and preterm labor with intact membranes, but it has not yet been investigated in women with preterm prelabor rupture of membranes (preterm PROM) in the presence/absence of detectable microorganisms. The aim of this study was to determine whether, among women with preterm PROM, there is an association between detectable microorganisms in amniotic fluid and intra-amniotic inflammation, and whether intra-amniotic inflammasome activation correlates with microbial burden. Methods Amniotic fluids from 59 cases of preterm PROM were examined for the presence/absence of microorganisms through culture and 16S ribosomal RNA (rRNA) gene quantitative real-time polymerase chain reaction (qPCR), and concentrations of interleukin-6 (IL-6) and ASC [apoptosis-associated spec-like protein containing a caspase recruitment domain (CARD)], an indicator of inflammasome activation, were determined. Results qPCR identified more microbe-positive amniotic fluids than culture. Greater than 50% of patients with a negative culture and high IL-6 concentration in amniotic fluid yielded a positive qPCR signal. ASC concentrations were greatest in patients with high qPCR signals and elevated IL-6 concentrations in amniotic fluid (i.e. intra-amniotic infection). ASC concentrations tended to increase in patients without detectable microorganisms but yet with elevated IL-6 concentrations (i.e. sterile intra-amniotic inflammation) compared to those without intra-amniotic inflammation. Conclusion qPCR is a valuable complement to microbiological culture for the detection of microorganisms in the amniotic cavity in women with preterm PROM, and microbial burden is associated with the severity of intra-amniotic inflammatory response, including inflammasome activation.

Using the new definition of intraamniotic infection - is there morbidity among the women left out?

Background: Recently, ACOG released updated definitions for intraamniotic infection (IAI): maternal fever (≥38.0 °C) and ≥1 symptom (fetal tachycardia, maternal white blood cell count >15,000/mm³ or purulent discharge). Treatment was no longer recommended for women with fever <39.0 °C plus maternal tachycardia or fundal tenderness (previous criteria). The objective of this study was to compare postpartum infectious morbidity among women meeting previous criteria (but not the new IAI criteria) to women meeting new IAI criteria.Methods: Retrospective cohort of women delivering vaginally at a single academic center. Demographics, antepartum and intrapartum characteristics of women who met diagnostic criteria for chorioamnionitis (previous criteria) compared to those who met IAI criteria using bivariate statistics. The primary outcome was a composite of postpartum infection, including: endometritis, perineal infection, sepsis, urinary tract infection, pyelonephritis. Backward-stepwise elimination used to estimate odds of primary outcome.Results: Of 229 women who met previous IAI criteria, 51 (22.3%) did not meet new IAI criteria. Women no longer meeting IAI criteria were younger (25 versus 27 years, p = .02), more likely to have gestational hypertension (16.0 versus 3.4%, p < .01), and less likely to have third or fourth degree lacerations (2.0 versus 13.4%, p = .02). No difference in antibiotic receipt was observed. Postpartum infection occurred in 16/229 (7.0%) women overall; five (9.8%) in those not meeting new IAI criteria, and 11 (6.2%) meeting new IAI criteria. After adjusting for confounders, there was no difference in odds of postpartum infection (aOR 1.65, 95% CI 0.55-4.99).Conclusions/implications: Among women who met old ACOG criteria for IAI, but not the new criteria, postpartum infection occurred in nearly 10%. This number could be higher if these women were not treated with antibiotics.