The current state of pertussis vaccination in pregnancy around the world, with recommendations for improved care: Consensus statements from the Global Pertussis Initiative

Bordetella pertussis, which causes a respiratory disease known as pertussis ("whooping cough") remains an important global challenge, with the incidence in pertussis cases increasing in recent years. Newborns and infants are at increased risk for severe morbidity and mortality from this bacterium. Vaccination in pregnancy has become an important strategy to both passively transfer immunity as well as prevent infection in pregnant persons, who are a major source of newborn infection, thus attempting to decrease the impact of this serious disease. It is considered safe for the pregnant person, the developing fetus, and the infant, and during the first 3 months of life it has been shown to be highly effective in preventing pertussis. There are a variety of strategies, recommendations, and adherence rates associated with pertussis vaccination in pregnancy around the world. We summarize the 2021 Global Pertussis Initiative Annual Meeting that reviewed the current global status of pertussis vaccination in pregnancy and remaining medical and scientific questions, with a focus on vaccination challenges and strategies for obstetric and gynecologic healthcare providers.

Neurodevelopmental Outcomes After Late Preterm Antenatal Corticosteroids: The ALPS Follow-Up Study

Importance

The Antenatal Late Preterm Steroids (ALPS) trial changed clinical practice in the United States by finding that antenatal betamethasone at 34 to 36 weeks decreased short-term neonatal respiratory morbidity. However, the trial also found increased risk of neonatal hypoglycemia after betamethasone. This follow-up study focused on long-term neurodevelopmental outcomes after late preterm steroids.

Objective

To evaluate whether administration of late preterm (34-36 completed weeks) corticosteroids affected childhood neurodevelopmental outcomes.

Design, Setting, and Participants

Prospective follow-up study of children aged 6 years or older whose birthing parent had enrolled in the multicenter randomized clinical trial, conducted at 13 centers that participated in the Maternal-Fetal Medicine Units (MFMU) Network cycle from 2011-2016. Follow-up was from 2017-2022.

Exposure

Twelve milligrams of intramuscular betamethasone administered twice 24 hours apart.

Main Outcome and Measures

The primary outcome of this follow-up study was a General Conceptual Ability score less than 85 (-1 SD) on the Differential Ability Scales, 2nd Edition (DAS-II). Secondary outcomes included the Gross Motor Function Classification System level and Social Responsiveness Scale and Child Behavior Checklist scores. Multivariable analyses adjusted for prespecified variables known to be associated with the primary outcome. Sensitivity analyses used inverse probability weighting and also modeled the outcome for those lost to follow-up.

Results

Of 2831 children, 1026 enrolled and 949 (479 betamethasone, 470 placebo) completed the DAS-II at a median age of 7 years (IQR, 6.6-7.6 years). Maternal, neonatal, and childhood characteristics were similar between groups except that neonatal hypoglycemia was more common in the betamethasone group. There were no differences in the primary outcome, a general conceptual ability score less than 85, which occurred in 82 (17.1%) of the betamethasone vs 87 (18.5%) of the placebo group (adjusted relative risk, 0.94; 95% CI, 0.73-1.22). No differences in secondary outcomes were observed. Sensitivity analyses using inverse probability weighting or assigning outcomes to children lost to follow-up also found no differences between groups.

Conclusion and Relevance

In this follow-up study of a randomized clinical trial, administration of antenatal corticosteroids to persons at risk of late preterm delivery, originally shown to improve short-term neonatal respiratory outcomes but with an increased rate of hypoglycemia, was not associated with adverse childhood neurodevelopmental outcomes at age 6 years or older.

The Association between Prenatal Nicotine Exposure and Offspring's Hearing Impairment

OBJECTIVES

 The objective of this study is to evaluate whether there is an association between in-utero exposure to nicotine and subsequent hearing dysfunction.

MATERIALS AND METHODS

 Secondary analysis of a multicenter randomized trial to prevent congenital cytomegalovirus (CMV) infection among gravidas with primary CMV infection was conducted. Monthly intravenous immunoglobulin hyperimmune globulin therapy did not influence the rate of congenital CMV. Dyads with missing urine, fetal or neonatal demise, infants diagnosed with a major congenital anomaly, congenital CMV infection, or with evidence of middle ear dysfunction were excluded. The primary outcome was neonatal hearing impairment in one or more ears defined as abnormal distortion product otoacoustic emissions (DPOAEs; 1 to 8 kHz) that were measured within 42 days of birth. DPOAEs were interpreted using optimized frequency-specific level criteria. Cotinine was measured via enzyme-linked immunosorbent assay kits in maternal urine collected at enrollment and in the third trimester (mean gestational age 16.0 and 36.7 weeks, respectively). Blinded personnel ran samples in duplicates. Maternal urine cotinine >5 ng/mL at either time point was defined as in-utero exposure to nicotine. Multivariable logistic regression included variables associated with the primary outcome and with the exposure (p < 0.05) in univariate analysis.

RESULTS

 Of 399 enrolled patients in the original trial, 150 were included in this analysis, of whom 46 (31%) were exposed to nicotine. The primary outcome occurred in 18 (12%) newborns and was higher in nicotine-exposed infants compared with those nonexposed (15.2 vs. 10.6%, odds ratio [OR] 1.52, 95% confidence interval [CI] 0.55-4.20), but the difference was not significantly different (adjusted odds ratio [aOR] = 1.0, 95% CI 0.30-3.31). This association was similar when exposure was stratified as heavy (>100 ng/mL, aOR 0.72, 95% CI 0.15-3.51) or mild (5-100 ng/mL, aOR 1.28, 95% CI 0.33-4.95). There was no association between nicotine exposure and frequency-specific DPOAE amplitude.

CONCLUSION

 In a cohort of parturients with primary CMV infection, nicotine exposure was not associated with offspring hearing dysfunction assessed with DPOAEs.

KEY POINTS

· Nicotine exposure was quantified from maternal urine.. · Nicotine exposure was identified in 30% of the cohort.. · Exposure was not associated with offspring hearing dysfunction..

Obstetric Racial Disparities in the Era of the ARRIVE (A Randomized Trial of Induction Versus Expectant Management) Trial and the Coronavirus Disease 2019 (COVID-19) Pandemic

OBJECTIVE

To evaluate the influence of the ARRIVE (A Randomized Trial of Induction Versus Expectant Management) trial and the coronavirus disease 2019 (COVID-19) pandemic on racial and ethnic differences in labor induction, pregnancy-associated hypertension, and cesarean delivery among non-Hispanic Black and non-Hispanic White low-risk, first-time pregnancies.

METHODS

We conducted an interrupted time series analysis of U.S. birth certificate data from maternal non-Hispanic Black and non-Hispanic White race and ethnicity, first pregnancy, 39 or more weeks of gestation, with no documented contraindication to vaginal delivery or expectant management beyond 39 weeks. We compared the rate of labor induction (primary outcome), pregnancy-associated hypertension, and cesarean delivery during three time periods: pre-ARRIVE (January 1, 2015-July 31, 2018), post-ARRIVE (November 1, 2018-February 29, 2020), and post-COVID-19 (March 1, 2020-December 31, 2021).

RESULTS

In the post-ARRIVE period, the rate of labor induction increased in both non-Hispanic White and non-Hispanic Black patients, with no statistically significant difference in the magnitude of increase between the two groups (rate ratio for race [RR race ] 0.98, 95% CI, 0.95-1.02, P =.289). Post-COVID-19, the rate of labor induction increased in non-Hispanic White but not non-Hispanic Black patients. The magnitude of the rate change between non-Hispanic White and non-Hispanic Black patients was significant (RR race 0.95, 95% CI, 0.92-0.99, P =.009). Non-Hispanic Black pregnant people were more likely to have pregnancy-associated hypertension and more often delivered by cesarean at all time periods.

CONCLUSION

Changes in obstetric practice after both the ARRIVE trial and the COVID-19 pandemic were not associated with changes in Black-White racial differences in labor induction, cesarean delivery, and pregnancy-associated hypertension.

Prenatal Vaccination Patterns among Birthing Individuals with History of Preterm Birth in the Pre- and Post-COVID Era

OBJECTIVE

 This study aims to explore vaccination acceptance among individuals with a history of preterm birth between March and June during the pre-COVID (2019), early-COVID (2020), and late-COVID (2021) periods.

STUDY DESIGN

 This is a cross-sectional, retrospective cohort study of pregnant individuals with a history of preterm birth (<37 weeks' gestation) who initiated care of a subsequent pregnancy during pre-COVID (March-June 2019), early-COVID (March-June 2020), or late-COVID (March-June 2021). The primary outcome of interest was vaccination status for influenza, Tdap, and COVID-19 vaccines. Fisher's exact and chi-square tests were used to investigate association between vaccination status and time periods, race/ethnicity, and insurance.

RESULTS

 Among 293 pregnancies, influenza vaccination rate was highest in early-COVID (p < 0.05). There was no statistically significant difference in Tdap or COVID-19 vaccination between time periods. COVID-19 vaccination was highest in individuals with private insurance (p < 0.05). There was no statistically significant difference in vaccination status by race/ethnicity.

CONCLUSION

 In this study on high-risk pregnant individuals, the majority of our cohort remained unvaccinated against COVID-19 into the late-COVID period. Additionally, their influenza vaccination rates were greater than the national average in early-COVID and substantially lower than the national average in late-COVID. This shift in influenza vaccination acceptance may have been sparked by COVID-19 vaccine distribution beginning in January 2021 leading to overall vaccination hesitancy. Standardized guidelines and counseling concerning prenatal safety in recommended immunizations may serve as important tools of reassurance and health promotion.

KEY POINTS

· Maternal infections during pregnancy are a risk factor for preterm birth.. · High-risk cohort had low influenza vaccination post-COVID possibly due to COVID-19 vaccine hesitancy.. · Vaccination education may be a uniquely important tool among high-risk pregnant patients..

RSV Prefusion F Protein-Based Maternal Vaccine - Preterm Birth and Other Outcomes

BACKGROUND

Vaccination against respiratory syncytial virus (RSV) during pregnancy may protect infants from RSV disease. Efficacy and safety data on a candidate RSV prefusion F protein-based maternal vaccine (RSVPreF3-Mat) are needed.

METHODS

We conducted a phase 3 trial involving pregnant women 18 to 49 years of age to assess the efficacy and safety of RSVPreF3-Mat. The women were randomly assigned in a 2:1 ratio to receive RSVPreF3-Mat or placebo between 24 weeks 0 days and 34 weeks 0 days of gestation. The primary outcomes were any or severe medically assessed RSV-associated lower respiratory tract disease in infants from birth to 6 months of age and safety in infants from birth to 12 months of age. After the observation of a higher risk of preterm birth in the vaccine group than in the placebo group, enrollment and vaccination were stopped early, and exploratory analyses of the safety signal of preterm birth were performed.

RESULTS

The analyses included 5328 pregnant women and 5233 infants; the target enrollment of approximately 10,000 pregnant women and their infants was not reached because enrollment was stopped early. A total of 3426 infants in the vaccine group and 1711 infants in the placebo group were followed from birth to 6 months of age; 16 and 24 infants, respectively, had any medically assessed RSV-associated lower respiratory tract disease (vaccine efficacy, 65.5%; 95% credible interval, 37.5 to 82.0), and 8 and 14, respectively, had severe medically assessed RSV-associated lower respiratory tract disease (vaccine efficacy, 69.0%; 95% credible interval, 33.0 to 87.6). Preterm birth occurred in 6.8% of the infants (237 of 3494) in the vaccine group and in 4.9% of those (86 of 1739) in the placebo group (relative risk, 1.37; 95% confidence interval [CI], 1.08 to 1.74; P = 0.01); neonatal death occurred in 0.4% (13 of 3494) and 0.2% (3 of 1739), respectively (relative risk, 2.16; 95% CI, 0.62 to 7.56; P = 0.23), an imbalance probably attributable to the greater percentage of preterm births in the vaccine group. No other safety signal was observed.

CONCLUSIONS

The results of this trial, in which enrollment was stopped early because of safety concerns, suggest that the risks of any and severe medically assessed RSV-associated lower respiratory tract disease among infants were lower with the candidate maternal RSV vaccine than with placebo but that the risk of preterm birth was higher with the candidate vaccine. (Funded by GlaxoSmithKline Biologicals; ClinicalTrials.gov number, NCT04605159.).

Breastfeeding Initiation, Duration, and Associated Factors Among People With Hepatitis C Virus Infection

OBJECTIVE

To characterize breastfeeding behaviors and identify factors associated with breastfeeding initiation among people with hepatitis C virus (HCV) infection.

METHODS

We conducted a secondary analysis of a multicenter observational cohort of pregnant people with singleton gestations and HCV seropositivity. This analysis includes individuals with data on breastfeeding initiation and excludes those with human immunodeficiency virus (HIV) co-infection. The primary outcome was self-reported initiation of breastfeeding or provision of expressed breast milk. Secondary outcomes included duration of breastfeeding. Demographic and obstetric characteristics were compared between those who initiated breastfeeding and those who did not to identify associated factors. Univariable and multivariable analyses were performed.

RESULTS

Overall, 579 individuals (75.0% of participants in the parent study) were included. Of those, 362 (62.5%) initiated breastfeeding or provided breast milk to their infants, with a median duration of breastfeeding of 1.4 months (interquartile range 0.5-6.0). People with HCV viremia , defined as a detectable viral load at any point during pregnancy, were less likely to initiate breastfeeding than those who had an undetectable viral load (59.4 vs 71.9%, adjusted odds ratio [aOR] 0.61, 95% CI, 0.41-0.92). People with private insurance were more likely to initiate breastfeeding compared with those with public insurance or no insurance (80.0 vs 60.1%; aOR 2.43, 95% CI, 1.31-4.50).

CONCLUSION

Although HCV seropositivity is not a contraindication to breastfeeding regardless of viral load, rates of breastfeeding initiation were lower among people with HCV viremia than among those with an undetectable viral load.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov , NCT01959321 .

Delta variant neutralizing antibody response following maternal COVID-19 vaccination

The Delta pandemic wave saw increased maternal morbidity and mortality compared to prior viral strains. COVID-19 vaccination in pregnancy elicits detectable levels of neutralizing antibodies to SARS-CoV-2 wild type and SARS-CoV-2 Delta variants in both maternal and neonatal samples at delivery. Our results demonstrate the effectiveness of vaccination which confers an immunological response against newer, and potentially more dangerous, viral variants.

Immunogenicity and safety of varying dosages of a fifth-wave influenza A/H7N9 inactivated vaccine given with and without AS03 adjuvant in healthy adults

BACKGROUND

Human infections with the avian influenza A(H7N9) virus were first reported in China in 2013 and continued to occur in annual waves. In the 2016/2017 fifth wave, Yangtze River Delta (YRD) lineage viruses, which differed antigenically from those of earlier waves, predominated.

METHODS

In this phase 2 double-blinded trial we randomized 720 adults ≥ 19 years of age to receive two injections of a YRD lineage inactivated A/Hong Kong/125/2017 fifth-wave H7N9 vaccine, given 21 days apart, at doses of 3.75, 7.5, and 15 µg of hemagglutinin (HA) with AS03A adjuvant and at doses of 15 and 45 µg of HA without adjuvant.

RESULTS

Two doses of adjuvanted vaccine were required to induce HA inhibition (HI) antibody titers ≥ 40 in most participants. After two doses of the 15 µg H7N9 formulation, given with or without AS03 adjuvant, the proportion achieving a HI titer ≥ 40 against the vaccine strain at 21 days after the second vaccination was 65 % (95 % CI, 57 %-73 %) and 0 % (95 % CI, 0 %-4%), respectively. Among those who received two doses of the 15 µg adjuvanted formulation the proportion with HI titer ≥ 40 at 21 days after the second vaccination was 76 % (95 % CI, 66 %-84 %) in those 19-64 years of age and 49 % (95 % CI, 37 %-62 %) in those ≥ 65 years of age. Responses to the adjuvanted vaccine formulations did not vary by HA content. Antibody responses declined over time and responses against drifted H7N9 strains were diminished. Overall, the vaccines were well tolerated but, as expected, adjuvanted vaccines were associated with more frequent solicited systemic and local adverse events.

CONCLUSIONS

AS03 adjuvant improved the immune responses to an inactivated fifth-wave H7N9 influenza vaccine, particularly in younger adults, but invoked lower responses to drifted H7N9 strains. These findings may inform future influenza pandemic preparedness strategies.

Risk Factors for Perinatal Transmission of Hepatitis C Virus

OBJECTIVE

To estimate the rate of perinatal transmission of hepatitis C virus (HCV) infection, to identify risk factors for perinatal transmission of HCV infection, and to determine the viremic threshold for perinatal transmission.

METHODS

This was a prospective, multicenter, observational study of pregnant individuals at less than 24 weeks of gestation screened for HCV infection from 2012 to 2018 in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network. Individuals found to be HCV antibody-positive were followed throughout pregnancy. Children were followed for evidence of perinatal transmission at 2-6 months (HCV RNA testing) and at 18-24 months (HCV RNA and antibody testing) of life. The primary outcome was perinatal transmission, defined as positive test results at either follow-up time point.

RESULTS

A total of 109,379 individuals were screened for HCV infection. Of the 1,224 participants who screened positive, 772 (63.1%) enrolled and 432 of those 772 (56.0%) had data available to assess primary outcome. The overall rate of perinatal transmission was 6.0% (26/432, 95% CI 4.0-8.7%). All children with HCV infection were born to individuals with demonstrable viremia. In viremic participants (n=314), the perinatal transmission rate was 8.0% (95% CI 5.2-11.5%). Risk factors for perinatal transmission included HCV RNA greater than 106 international units/mL (adjusted odds ratio [aOR] 8.22, 95% CI 3.16-21.4) and vaginal bleeding reported at any time before delivery (aOR 3.26, 95% CI 1.32-8.03). A viremic threshold for perinatal transmission could not be established.

CONCLUSION

Perinatal transmission of HCV infection was limited to viremic individuals. High viral loads and antepartum bleeding were associated with perinatal transmission.

Factors Associated with Guideline Concordant Clinician Counseling about Low-Dose Aspirin to Prevent Preeclampsia in Nulliparous Patients

OBJECTIVE

 The primary aim of this study was to examine the United States Preventative Services Task Force (USPSTF) guidelines concordant low-dose aspirin (LDA) counseling and factors associated with counseling in nulliparous birthing individuals.

STUDY DESIGN

 We conducted a retrospective cohort study of nulliparous birthing individuals who delivered between January 1, 2019 and June 30, 2020 and received prenatal care at the Duke High Risk Obstetrical Clinics (HROB). All nulliparous patients over 18 years old who established or transferred care to HROB by 16 weeks, 6 days were included in the analysis. We excluded patients with more than two previous first-trimester pregnancy losses, multiple gestation, a known contraindication to LDA, initiation of LDA prior to their prenatal care, or documented medical history of coagulation disorder. Bivariate associations between demographic/medical characteristics and our primary outcome, receipt of counseling (yes/no), were assessed using two-sample t-tests for continuous variables and chi-square or Fisher's exact test for categorical variables. Factors significantly associated with the primary outcome (p < 0.05) were entered into the multivariable logistic regression model.

RESULTS

 Among 391 birthing individuals included in the final analysis cohort, 51.7% of eligible patients received guideline consistent LDA counseling. Factors associated with increased odds of LDA counseling were advanced maternal age (adjusted odds ratio [aOR]: 1.05, 95% confidence interval [CI]: 1.01-1.09), Black race compared with White race (aOR:1.75, 95% CI: 1.03-2.98), chronic hypertension (aOR: 4.17, 95% CI: 1.82-9.55), and obesity (aOR: 5.02, 95% CI: 3.12-8.08).

CONCLUSION

 Approximately half of all nulliparous birthing individuals had appropriately documented LDA counseling. The USPSTF guidelines on LDA for preeclampsia risk reduction are complex, which may lead to ineffective provider adherence. Efforts to simplify guidelines and improve LDA counseling are vital to ensuring this low-cost, evidence-based preeclampsia prevention is used in a consistent and equitable manner.

KEY POINTS

· A total of 51.7% of eligible patients received guideline consistent LDA counseling.. · Advanced maternal age , body mass index > 30, Black race, and chronic hypertension associated with increased odds of counseling.. · Among patients most likely to be counseled, high numbers did not receive LDA counseling..

Maternal and Delivery Characteristics and Self-Reported Perceived Control During Labor

OBJECTIVE

To evaluate the association between maternal and delivery characteristics and self-reported perceived control during childbirth.

METHODS

A secondary analysis of a multicenter randomized trial was conducted to compare labor induction at 39 weeks of gestation with expectant management in low-risk nulliparous people. Six to 96 hours after delivery, participants who experienced labor completed the Labor Agentry Scale, a validated self-administered questionnaire to ascertain perceived control during childbirth. Scores range from 29 to 203, with higher scores indicating a sense of greater control. Multivariable linear regression was used to determine which maternal and delivery characteristics were associated with the Labor Agentry Scale score. Eligible characteristics included age, self-reported race and ethnicity, marital status, employment status, type of insurance, previous pregnancy loss before 20 weeks of gestation, body mass index (BMI), smoking, alcohol use, mode of delivery, labor pain (0-10 points), and a composite of perinatal death or severe neonatal complications. Significant variables ( P <.05) were retained in the final multivariable model, and adjusted mean differences (95% CIs) between groups were estimated.

RESULTS

Of 6,106 people enrolled in the trial, 6,038 experienced labor, of whom 5,750 (95.2%) completed the Labor Agentry Scale and were included in this analysis. Mean [95% CI] adjusted Labor Agentry Scale scores were significantly lower among those who identified as Asian (-6.4 [-10.5 to -2.3]) or Hispanic (-3.7 [-5.7 to -1.7]) compared with White, smoked compared with did not smoke (-2.8 [-5.5 to -0.1]), had BMIs of 35 or higher compared with less than 30 (-2.0 [-3.8 to -0.2]), were unemployed (-3.15 [-4.76 to -1.55]), did not have private health insurance (-2.61 [-4.47 to -0.76]), underwent operative vaginal (-5.1 [-7.7 to -2.6]) or cesarean (-14.4 [-16.1 to -12.6]) delivery compared with spontaneous vaginal delivery, and reported greater labor pain score of 8 or higher compared with less than 8 (-11.9 [-13.4 to -10.4]). Mean [95% CI] adjusted Labor Agentry Scale scores were significantly higher among people who were employed compared with unemployed (3.2 [1.6-4.8]) and had private compared with nonprivate insurance (2.6 [0.76-4.5]).

CONCLUSION

In nulliparous people at low risk, unemployment, lack of private health insurance, Asian race, Hispanic ethnicity, smoking, operative delivery, and more labor pain were associated with lower perceived control during labor.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov , NCT01990612.

Efficacy and safety of azithromycin versus placebo to treat lower respiratory tract infections associated with low procalcitonin: a randomised, placebo-controlled, double-blind, non-inferiority trial

BACKGROUND

Lower respiratory tract infections are frequently treated with antibiotics, despite a viral cause in many cases. It remains unknown whether low procalcitonin concentrations can identify patients with lower respiratory tract infection who are unlikely to benefit from antibiotics. We aimed to compare the efficacy and safety of azithromycin versus placebo to treat lower respiratory tract infections in patients with low procalcitonin.

METHODS

We conducted a randomised, placebo-controlled, double-blind, non-inferiority trial at five health centres in the USA. Adults aged 18 years or older with clinically suspected non-pneumonia lower respiratory tract infection and symptom duration from 24 h to 28 days were eligible for enrolment. Participants with a procalcitonin concentration of 0·25 ng/mL or less were randomly assigned (1:1), in blocks of four with stratification by site, to receive over-encapsulated oral azithromycin 250 mg or matching placebo (two capsules on day 1 followed by one capsule daily for 4 days). Participants, non-study clinical providers, investigators, and study coordinators were masked to treatment allocation. The primary outcome was efficacy of azithromycin versus placebo in terms of clinical improvement at day 5 in the intention-to-treat population. The non-inferiority margin was -12·5%. Solicited adverse events (abdominal pain, vomiting, diarrhoea, allergic reaction, or yeast infections) were recorded as a secondary outcome. This trial is registered with ClinicalTrials.gov, NCT03341273.

FINDINGS

Between Dec 8, 2017, and March 9, 2020, 691 patients were assessed for eligibility and 499 were enrolled and randomly assigned to receive azithromycin (n=249) or placebo (n=250). Clinical improvement at day 5 was observed in 148 (63%, 95% CI 54 to 71) of 238 participants with full data in the placebo group and 155 (69%, 61 to 77) of 227 participants with full data in the azithromycin group in the intention-to-treat analysis (between-group difference -6%, 95% CI -15 to 2). The 95% CI for the difference did not meet the non-inferiority margin. Solicited adverse events and the severity of solicited adverse events were not significantly different between groups at day 5, except for increased abdominal pain associated with azithromycin (47 [23%, 95% CI 18 to 29] of 204 participants) compared with placebo (35 [16%, 12 to 21] of 221; between-group difference -7% [95% CI -15 to 0]; p=0·066).

INTERPRETATION

Placebo was not non-inferior to azithromycin in terms of clinical improvement at day 5 in adults with lower respiratory tract infection and a low procalcitonin concentration. After accounting for both the rates of clinical improvement and solicited adverse events at day 5, it is unclear whether antibiotics are indicated for patients with lower respiratory tract infection and a low procalcitonin concentration.

FUNDING

National Institute of Allergy and Infectious Diseases, bioMérieux.

Evaluation of Hypoglycemia in Neonates of Women at Risk for Late Preterm Delivery: An Antenatal Late Preterm Steroids Trial Cohort Study

OBJECTIVE

 In the antenatal late preterm steroids (ALPS) trial betamethasone significantly decreased short-term neonatal respiratory morbidity but increased the risk of neonatal hypoglycemia, diagnosed only categorically (<40 mg/dL). We sought to better characterize the nature, duration, and treatment for hypoglycemia.

STUDY DESIGN

 Secondary analysis of infants from ALPS, a multicenter trial randomizing women at risk for late preterm delivery to betamethasone or placebo. This study was a reabstraction of all available charts from the parent trial, all of which were requested. Unreviewed charts included those lost to follow-up or from sites not participating in the reabstraction. Duration of hypoglycemia (<40 mg/dL), lowest value and treatment, if any, were assessed by group. Measures of association and regression models were used where appropriate.

RESULTS

 Of 2,831 randomized, 2,609 (92.2%) were included. There were 387 (29.3%) and 223 (17.3%) with hypoglycemia in the betamethasone and placebo groups, respectively (relative risk [RR]: 1.69, 95% confidence interval [CI]: 1.46-1.96). Hypoglycemia generally occurred in the first 24 hours in both groups: 374/385 (97.1%) in the betamethasone group and 214/222 (96.4%) in the placebo group (p = 0.63). Of 387 neonates with hypoglycemia in the betamethasone group, 132 (34.1%) received treatment, while 73/223 (32.7%) received treatment in placebo group (p = 0.73). The lowest recorded blood sugar was similar between groups. Most hypoglycemia resolved by 24 hours in both (93.0 vs. 89.3% in the betamethasone and placebo groups, respectively, p = 0.18). Among infants with hypoglycemia in the first 24 hours, the time to resolution was shorter in the betamethasone group (2.80 [interquartile range: 2.03-7.03) vs. 3.74 (interquartile range: 2.15-15.08) hours; p = 0.002]. Persistence for >72 hours was rare and similar in both groups, nine (2.4%, betamethasone) and four (1.9%, placebo, p = 0.18).

CONCLUSION

 In this cohort, hypoglycemia was transient and most received no treatment, with a quicker resolution in the betamethasone group. Prolonged hypoglycemia was uncommon irrespective of steroid exposure.

KEY POINTS

· Hypoglycemia was transient and approximately two-thirds received no treatment.. · Neonates in the ALPS trial who received betamethasone had a shorter time to resolution than those with hypoglycemia in the placebo group.. · Prolonged hypoglycemia occurred in approximately 2 out of 100 late preterm newborns, irrespective of antenatal steroid exposure..

Safety and Immunogenicity of Influenza A/H5N8 Virus Vaccine in Healthy Adults: Durability and Cross-reactivity of Antibody Responses

BACKGROUND

Influenza A/H5N8 viruses infect poultry and wild birds in many countries. In 2021, the first human A/H5N8 cases were reported.

METHODS

We conducted a phase I, cohort-randomized, double-blind, controlled trial of inactivated influenza A/H5N8 vaccine (clade 2.3.4.4c) administered with or without adjuvant. Cohort 1 subjects received either two doses of AS03-adjuvanted vaccine containing 3.75 μg or 15 μg hemagglutinin (HA); two doses of 15 μg HA unadjuvanted vaccine; or one dose of AS03-adjuvanted vaccine (3.75 μg or 15 μg HA), followed by one dose of non-adjuvanted vaccine (same HA content). Cohort 2 subjects received two doses of MF59-adjuvanted vaccine containing 3.75 μg or 15 μg HA, or 15 μg HA of non-adjuvanted vaccine. Subjects were followed for 13 months for safety and immunogenicity.

RESULTS

We enrolled 386 adult subjects in good health. Solicited adverse events were generally mild and more common among subjects who received adjuvanted vaccines. Antibody responses (hemagglutination inhibition or microneutralization assays) were highest in the two-dose AS03 group, followed by the one-dose AS03 group, the MF59 groups, and the non-adjuvanted groups. Antibody levels returned to baseline 12 months after the second vaccination in all groups except the 15 μg AS03-adjuvanted group. Cross-reactive antibodies to clade 2.3.4.4b strains isolated from recent human cases were demonstrated in a subset of both 15 μg adjuvanted groups.

CONCLUSIONS

Two doses of influenza A/H5N8 vaccine were well-tolerated. Immunogenicity improved with receipt of two doses of adjuvanted vaccine and higher antigen content. (Funded by the National Institute of Allergy and Infectious Diseases.

Population Pharmacokinetics of Piperacillin/Tazobactam Across the Adult Lifespan

BACKGROUND AND OBJECTIVE

Piperacillin/tazobactam is one of the most frequently used antimicrobials in older adults. Using an opportunistic study design, we evaluated the pharmacokinetics of piperacillin/tazobactam as a probe drug to evaluate changes in antibacterial drug exposure and dosing requirements, including in older adults.

METHODS

A total of 121 adult patients were included. The population pharmacokinetic models that best characterized the observed plasma concentrations of piperacillin and tazobactam were one-compartment structural models with zero-order input and linear elimination.

RESULTS

Among all potential covariates, estimated creatinine clearance had the most substantial impact on the elimination clearance for both piperacillin and tazobactam. After accounting for renal function and body size, there was no remaining impact of frailty on the pharmacokinetics of piperacillin and tazobactam. Monte Carlo simulations indicated that renal function had a greater impact on the therapeutic target attainment than age, although these covariates were highly correlated. Frailty, using the Canadian Study of Health and Aging Clinical Frailty Scale, was assessed in 60 patients who were ≥ 65 years of age.

CONCLUSIONS

The simulations suggested that adults ≤ 50 years of age infected with organisms with higher minimum inhibitory concentrations may benefit from continuous piperacillin/tazobactam infusions (12 g/day of piperacillin component) or extended infusions of 4 g every 8 hours. However, for a target of 50% fT + minimum inhibitory concentration, dosing based on renal function is generally preferable to dosing by age, and simulations suggested that patients with creatinine clearance ≥ 120 mL/min may benefit from infusions of 4 g every 8 hours for organisms with higher minimum inhibitory concentrations.

IMPaCT: A Pilot Randomized Trial of an Intervention to Reduce Preterm Birth Among Non-Hispanic Black Patients at High Risk

Introduction

Preterm birth is a major cause of neonatal morbidity and mortality rate. Non-Hispanic black patients disproportionately experience preterm birth and nonadherence to evidence-based preventive measures. Interventions tailored to non-Hispanic black birthing individuals (NHBBIs) that address barriers to preterm birth preventions are urgently needed.

Methods

Together with a community-engaged multidisciplinary stakeholder group, we developed an intervention to improve adherence to preterm birth preventions among black pregnant patients with prior preterm birth. The intervention included the following: (1) preterm birth prevention education, (2) an employment navigation toolkit, and (3) encouragement text messages. We piloted the intervention by recruiting self-identified non-Hispanic black patients at or before 20 weeks of gestation with a prior preterm birth and randomizing them to the intervention or an active control. The primary outcomes were feasibility and acceptability. Our secondary outcomes were preliminary efficacy based on birth outcomes, patient experience, and pregnancy-specific anxiety (PSA). Descriptive statistics, analysis of verbatim survey responses, Wilcoxon signed rank, and Fisher's exact were used to describe and compare quantitative and qualitative data.

Results

We identified 53 individuals who met the inclusion criteria, 35 were reachable remotely and 30 were enrolled and randomized. More than 80% (n=26) were retained throughout the study, and 100% of participants identified at least one intervention component as helpful. In this small pilot, there were no detectable differences in adherence to preterm birth preventive recommendations. No difference in preterm births, other pregnancy, or patient experience outcomes was detected between the intervention and active control participants.

Discussion

The intervention is feasible and acceptable. Larger, appropriately powered studies are needed to assess whether the intervention will decrease PSA and reduce preterm birth. This trial was registered with ClinicalTrials.gov (NCT04933812).

Racial and ethnic representation in 17-hydroxyprogesterone caproate preterm birth prevention studies: a systematic review

OBJECTIVES

The US preterm birth rate varies dramatically by race and ethnicity yet the racial and ethnic representation within studies evaluating 17-hydroxprogesterone caproate (17-P) for preterm birth prevention is unknown. The objectives of our study were to 1) examine the racial and ethnic representation of participants in 17-P preterm birth prevention studies, 2) evaluate adherence to the NIH race and ethnicity reporting guidelines and 3) compare racial and ethnic representation in research studies to national preterm birth incidence.

METHODS

We systematically reviewed US studies published between January 2000 and December 2019. Study participant's race and ethnicity were reported using descriptive statistics then compared to US 2017//2018 preterm birth data using Pearson's chi-square.

RESULTS

Eighteen studies met the inclusion criteria, 17 studies reported race, 11 studies reported ethnicity, and yet none of the studies followed the NIH criteria. Compared to 2017/2018 US preterm births, the proportion of black/African American study participants was significantly higher whereas the proportions of all other race categories were lower.

CONCLUSIONS

More detailed reporting of race and ethnicity is needed in 17-P literature. Black women appear to be well represented while other racial and ethnic groups may be understudied.

Hypertension in pregnancy and adverse outcomes among low-risk nulliparous women expectantly managed at or after 39 weeks: a secondary analysis of a randomised controlled trial

OBJECTIVE

To evaluate whether hypertensive disorders of pregnancy (HDP) among low-risk nulliparous women expectantly managed at or after 39 weeks of gestation are associated with adverse outcomes.

DESIGN

Secondary analysis of a randomised trial.

SETTING

Multicentre, USA.

POPULATION

Individuals in the expectantly managed group who delivered on or after 39 weeks.

METHODS

Multivariable analysis to estimate adjusted relative risks (aRR) for binomial outcomes, adjusted odds ratios (aOR) for multinomial outcomes and 95% CI.

MAIN OUTCOME MEASURES

Composite adverse maternal outcome including placental abruption, pulmonary oedema, postpartum haemorrhage, postpartum infection, venous thromboembolism or intensive care unit admission. Secondary outcomes included a composite of perinatal death or severe neonatal complications, mode of delivery, small and large for gestational age and neonatal intermediate or intensive unit length of stay.

RESULTS

Of the 3044 women randomised to expectant management in the original trial, 2718 (89.3%) were eligible for this analysis, of whom 373 (13.7%) developed HDP. Compared with participants who remained normotensive, those who developed HDP were more likely to experience the maternal composite (12% versus 6%, aRR 1.84, 95% CI 1.33-2.54) and caesarean delivery (29% versus 23%, aOR 1.32, 95% CI 1.01-1.71). Differences between the two groups were not significantly different for the adverse perinatal composite (7% versus 5%, aRR 1.38, 95% CI 0.92-2.07) or for other secondary outcomes.

CONCLUSION

Almost 14% of low-risk nulliparous individuals expectantly managed at 39 weeks developed HDP, and were more likely to experience adverse maternal outcomes compared with those who did not develop HDP.

TWEETABLE ABSTRACT

Almost 14% of low-risk nulliparous individuals expectantly managed at 39 weeks developed hypertensive disorders of pregnancy, and were more likely to experience adverse maternal outcomes compared with those who did not develop hypertensive disorders.

Preparing for Disease X: Ensuring Vaccine Equity for Pregnant Women in Future Pandemics

Disease X represents a yet unknown human pathogen which has potential to cause a serious international epidemic or pandemic. The COVID-19 pandemic has illustrated that despite being at increased risk of severe disease compared with the general population, pregnant women were left behind in the development and implementation of vaccination, resulting in conflicting communications and changing guidance about vaccine receipt in pregnancy. Based on the COVID-19 experience, the COVAX Maternal Immunization Working Group have identified three key factors and five broad focus topics for consideration when proactively planning for a disease X pandemic, including 10 criteria for evaluating pandemic vaccines for potential use in pregnant women. Prior to any disease X pandemic, collaboration and coordination are needed to close the pregnancy data gap which is currently a barrier to gender equity in health innovation, which will aid in allowing timely access to life-saving interventions including vaccines for pregnant women and their infants.

A Qualitative Study Documenting Black Birthing Individuals' Perspectives on the Disproportionate Rate of Preterm Birth in the Black Community

Background:

Compared with all other racial and ethnic groups, the rate of preterm birth (PTB) is 50% higher among non-Hispanic Blacks (NHB). There are limited published data focused on the etiology of the racial disparity in PTB from the perspective of Black birthing individuals who have had a lived experience with PTB.

Methods:

To gain insights into the etiology of the race disparity in PTB from the NHB patient's perspective, we conducted a qualitative descriptive study with NHBs who have a history of PTB. We conducted both focus group discussions (FGDs), in-depth interviews (IDIs), and used applied thematic analysis to analyze the data.

Results:

Seven individuals participated in 3 FGDs and 15 individuals participated in an IDI. The majority of participants named stress as a contributor to PTB among NHBs. Participants described that stress becomes an ongoing cycle with a cumulative effect on health. Three primary sources of stress were identified: (1) individual including stress from lack of personal wellness, (2) relational stress from intimate partner and familial relationships, and (3) community-level stress from occupations and societal expectations.

Conclusion:

Uncovering NHB patient's perspectives on the etiology of PTB is a critical step to develop interventions that mitigate the disparity impacting the Black community. Our findings suggest that multilevel interventions targeting individual-, relational-, and community-level stress may be necessary to reduce rates of PTB among NHB individuals.

Understanding COVID-19 vaccine uptake during pregnancy: 'Hesitance', knowledge, and evidence-based decision-making

Background

A key mitigation strategy to the COVID-19 pandemic has been the development and roll-out of vaccines. However, pregnant and lactating people were not included in initial vaccine trials and this population is hesitant to receive the vaccine, despite contrary recommendations from the American College of Obstetrics and Gynecology and the Centers for Disease Control and Prevention. Understanding the reasons behind this hesitancy is vital to promote vaccine uptake.

Methods

We surveyed pregnant people in California from December 2020 to January 2021 (n = 387) to describe cognitions and decision-making regarding COVID-19 vaccination. Using descriptive, regression-based analyses, we examined rates of planned uptake and reasoning among individuals who reported COVID-19 vaccine hesitancy.

Results

Overall, the pregnant Californians that we surveyed were aware of the COVID-19 vaccines. Of 387 participants, 43% reported planning to get the vaccine as soon as possible. The remaining 57% were hesitant: 27% responded that they would not receive the vaccine. Some demographic features did predict more COVID-19 vaccine hesitancy, particularly younger age (AOR = 0.95, p = 0.025) and living in a less urban context (AOR = 0.80, p = 0.041). Essential worker status also was associated with vaccine hesitancy. Having had, or intending to have, a flu vaccine was negatively associated with COVID-19 vaccine hesitancy (p < 0.001). The most commonly reported reason for COVID-19 vaccine hesitancy was “I don’t know enough about the vaccine.” Low levels of self-reported knowledge were highly predictive of hesitancy.

Conclusions

Terms like “vaccine hesitance” and “anti-vax” do not adequately characterize decisions regarding delaying COVID-19 vaccination. Rather, these decisions are largely based on the lack of knowledge about the impacts of vaccination on pregnancy, fetal development, and later child wellbeing. This lack of knowledge should be countered by conversations between individual healthcare providers and their pregnant patients, and better inclusion of pregnant people and children in vaccine trials.

Symptomatic versus asymptomatic COVID-19: does it impact placental vasculopathy?

This study sought to assess the impact of COVID-19 on placental vasculature in the context of maternal symptomatology - comparing asymptomatic to symptomatic pregnant patients - and disease severity - comparing pregnant patients with mild, moderate, severe, and critical COVID-19 infection. PCR-confirmed COVID-19 positive pregnant patients in a single health system who delivered between 3/2020-5/2021 included. All patients had positive COVID test and delivered during the study period. Primary outcome was incidence of any vascular malperfusion on placental pathology. Secondary outcomes were FVM and MVM on placental pathology. Placental pathology compared between symptomatic (sCOVID) and asymptomatic (aCOVID) patients. Secondary analysis of symptomatic patients, comparing placental pathology between mild disease(mCOVID) and worse disease(moderate, severe, or critical-defined by 2020 NIH guidelines) (dCOVID), also performed. Of 112 patients, 53 (47%) had symptoms. Twenty-seven (24.1%) patients had evidence of vascular malperfusion; 26 (23.2%) had MVM. When comparing aCOVID and sCOVID patients, no difference in rate of vascular malperfusion identified, nor any differences in rates of FVM or MVM. Among sCOVID patients (n = 53), 39 (74%) had mCOVID and 14 (26%) had dCOVID (moderate n = 4, severe n = 9, critical n = 1). Patients with dCOVID had earlier median delivery GA (37.4wks vs 39.2wks, p = .03). No difference in latency from diagnosis to delivery seen between mCOVID and dCOVID groups (4.4 vs 3.0wks, p = .96). Twelve (30.8%) patients had vascular malperfusion on pathology, all had mCOVID (p = .02). Eleven (28.2%) mCOVID patients had MVM; no dCOVID patients had evidence of vascular malperfusion (p = .03). No difference in FVM was found between cohorts. Symptomatic COVID-19 infection did not impact placental vasculature differently than asymptomatic infection, even when stratifying by trimester of infection. Among pregnant patients with symptomatic COVID-19, mild disease was associated with placental vascular changes on the maternal side while severe disease was not. Further studies are needed to understand the implications of these findings.

Estimated Prevalence of Risk Factors for Preeclampsia Among Individuals Giving Birth in the US in 2019

IMPORTANCE

Low-dose aspirin (LDA) is one of the few evidence-based interventions for preventing preeclampsia, which is a leading cause of maternal or fetal morbidity and mortality. Current guidelines recommend LDA based on the presence of risk factors for preeclampsia, but the population-based prevalence of these factors is unknown.

OBJECTIVE

To estimate population-level prevalence of preeclampsia risk factors used in prophylactic LDA guidelines for pregnant patients and the association of these risk factors with reported rates of pregnancy-related hypertension.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective cohort study was conducted using National Center for Health Statistics birth certificate data to describe the frequency of pregnant individuals with moderate to high-risk factors for preeclampsia and pregnancy-related hypertension rates. The study used all birth records in the United States for the 2019 calendar year.

EXPOSURES

Documentation of preeclampsia risk factors: multifetal gestation, pregestational diabetes, chronic hypertension (high-risk factors) and nulliparity, a body mass index greater than 30, African American race, a maternal age 35 years or older, an interval of more than 10-years since last birth, and having low socioeconomic status (moderate risk factors).

MAIN OUTCOMES AND MEASURES

Prevalence of each risk factor alone and in combinations leading to a recommendation for LDA; incidence of pregnancy-related hypertension by risk factor and combinations of risk factors.

RESULTS

There were 3 695 019 pregnancies in 2019, including 528 778 with no risk factors, 169 540 with 1 or more high-risk factors, and 2 996 701 with 1 or more moderate-risk factors. The mean (SD) of the cohort was 29.1 (5.8) years. Multifetal gestation was the most common high-risk factor and found in 123 995 pregnancies (3.4%), and low socioeconomic status was the most common moderate-risk factor and present in 1 732 729 pregnancies (46.9%). Based on 2021 criteria (a single high- or moderate-risk factors for preeclampsia), 3 166 241 pregnant patients (85.7%) were eligible for LDA. The incidence of pregnancy-related hypertension increased with the number of moderate-risk factors. The 2021 guidelines suggest considering or recommend LDA in 92.3% of pregnancies diagnosed with pregnancy-related hypertension.

CONCLUSIONS AND RELEVANCE

These data support the recently published guidelines and suggest further simplified guidelines recommending LDA to patients with any single moderate-risk factors.

Morbidity of late-season influenza during pregnancy

BACKGROUND

In the Northern Hemisphere, influenza season typically starts in December and lasts through March. Pregnant people are at increased risk for influenza-related morbidity and mortality. Potentially, new viral strains or reduced provider suspicion leading to delayed diagnosis of late-season influenza could result in an increased risk of severe infection.

OBJECTIVE

This study aimed to assess the incidence and morbidity associated with late-season influenza in pregnancy, compared with influenza in other seasons.

STUDY DESIGN

This was a retrospective cohort study using the 2007-2018 National Inpatient Sample. Pregnant patients with discharge diagnosis codes consistent with influenza infection were compared on the basis of hospital admission quarter (quarter 1: October to December; quarter 2: January to March; quarter 3: April to June; quarter 4: July to September), with quarter 3 defined as "late-season." The primary outcome was the severe maternal morbidity composite defined by the Centers for Disease Control and Prevention. The secondary outcomes included sepsis, shock, acute renal failure, acute heart failure, temporary tracheostomy, and invasive mechanical ventilation. Associations between outcomes and quarter of infection were adjusted for age, hospitalization type (antepartum, delivery, or postpartum), and comorbid conditions using relative risk regression, weighted to reflect the National Inpatient Sample design.

RESULTS

Of 7355 hospitalizations, corresponding to a weighted national estimate of 36,042, 2266 (30.8%) occurred in quarter 1, 4051 (55.0%) in quarter 2, 633 (8.6%) in quarter 3, and 405 (5.5%) in quarter 4. A nonsignificant trend toward higher rates of severe maternal morbidity was seen in the "late-season" compared with other quarters (13.9% [quarter 3] vs 10.5% [quarter 1] vs 12.1% [quarter 2] vs 13.6% [quarter 4]; P=.07). Moreover, sepsis was more common in patients with late-season influenza (8.0% [quarter 3] vs 4.8% [quarter 1] vs 5.8% [quarter 2] vs 5.9% [quarter 4]; P=.03). In the adjusted analyses, patients with late-season influenza had a 1.34 (95% confidence interval, 1.01-1.78) higher risk of severe maternal morbidity and 1.57 (95% confidence interval, 1.06-2.32) higher risk of sepsis than patients with influenza in quarter 1.

CONCLUSION

Influenza infection between April and June, that is, late-season influenza, is associated with a higher risk of severe maternal morbidity and sepsis in pregnant patients. Obstetrical providers must continue to have awareness and suspicion for influenza infection during these months.

Maternal and Neonatal Outcomes in Nulliparous Participants Undergoing Labor Induction by Cervical Ripening Method

OBJECTIVE

 This study aimed to evaluate maternal and neonatal outcomes by method of cervical ripening for labor induction among low-risk nulliparous individuals.

STUDY DESIGN

 This is a secondary analysis of a multicenter randomized trial of labor induction at 39 weeks versus expectant management in low-risk nulliparous participants. Participants undergoing cervical ripening for labor induction in either group were included. Participants were excluded for preripening membrane rupture, abruption, chorioamnionitis, fetal demise, or cervical dilation ≥3.5 cm. Cervical ripening was defined by the initial method used: prostaglandin only (PGE; referent), Foley with concurrent prostaglandin (Foley-PGE), Foley only (Foley), and Foley with concurrent oxytocin (Foley-oxytocin). Coprimary outcomes were adverse maternal and neonatal composites. Secondary outcomes included cesarean delivery and length of labor and delivery (L&D) stay. Multivariable analysis was used to adjust for patient characteristics.

RESULTS

 Of 6,106 participants included in the trial, 2,376 (38.9%) met criteria for this analysis. Of these, 1,247 (52.4%) had cervical ripening with PGE, 290 (12.2%) had Foley-PGE, 385 (16.2%) had Foley, and 454 (19.1%) had Foley-oxytocin. The maternal composite outcome was similar among participants who received Foley-PGE (24.1%, adjusted relative risk [aRR] = 1.21, 95% confidence interval [CI]: 0.96-1.52), Foley (21.3%, aRR = 1.16, 95% CI: 0.92-1.45), or Foley-oxytocin (19.4%, aRR = 1.04, 95% CI: 0.83-1.29), compared with PGE (19.7%). The neonatal composite outcome was less frequent in participants who received the Foley-PGE (2.4%, aRR = 0.35, 95% CI: 0.16-0.75) or Foley (3.6%, aRR = 0.51, 95% CI: 0.29-0.89) but did not reach statistical significance for participants who received Foley-oxytocin (4.6%, aRR = 0.63, 95% CI: 0.40-1.01) compared with PGE only (6.8%). Participants who received Foley-PGE or Foley-oxytocin had a shorter L&D stay (adjusted mean difference = -1.97 hours, 95% CI: -3.45 to -0.49 and -5.92 hours, 95% CI: -7.07 to -4.77, respectively), compared with PGE.

CONCLUSION

 In term low-risk nulliparous participants, Foley alone or concurrent with PGE is associated with a lower risk of adverse neonatal outcomes than with PGE alone. Length of L&D stay was the shortest with concurrent Foley-oxytocin.

KEY POINTS

· Adverse maternal outcomes are similar among different methods of cervical ripening in low-risk women.. · Adverse neonatal outcomes are less frequent with use of Foley alone or in combination with PGE.. · The use of Foley alone, or in combination with other agents, appears to be beneficial..

Maternal and Neonatal Outcomes Associated with Amniotomy among Nulliparous Women Undergoing Labor Induction at Term

OBJECTIVE

The aim of the study is to evaluate the association between amniotomy at various time points during labor induction and maternal and neonatal outcomes among term, nulliparous women.

STUDY DESIGN

Secondary analysis of a randomized trial of term labor induction versus expectant management in low-risk, nulliparous women (2014-2017) was conducted. Women met inclusion criteria if they underwent induction ≥38 weeks' gestation using oxytocin with documented time and type of membrane rupture. Women with antepartum stillbirth or fetal anomaly were excluded. The primary outcome was cesarean delivery. Secondary outcomes included maternal and neonatal complications. Maternal and neonatal outcomes were compared among women with amniotomy versus women with intact membranes and no amniotomy at six 2-hour time intervals: before oxytocin initiation, 0 to <2 hours after oxytocin, 2 to <4 hours after, 4 to <6 hours after, 6 to <8 hours after, and 8 to <10 hours after. Multivariable logistic regression adjusted for maternal age, body mass index, race/ethnicity, modified Bishop score on admission, treatment group, and hospital (as a random effect).

RESULTS

Of 6,106 women in the parent trial, 2,854 (46.7%) women met inclusion criteria. Of these 2,340 (82.0%) underwent amniotomy, and majority of the women had amniotomy performed between 2 and <6 hours after oxytocin. Cesarean delivery was less frequent among women with amniotomy 6 to <8 hours after oxytocin compared with women without amniotomy (21.9 vs. 29.7%; adjusted odds ratio 0.61, 95% confidence interval 0.42-0.89). Amniotomy at time intervals ≥4 hours after oxytocin was associated with lower odds of labor duration >24 hours. Amniotomy at time intervals ≥2 hours and <8 hours after oxytocin was associated with lower odds of maternal hospitalization >3 days. Amniotomy was not associated with postpartum or neonatal complications.

CONCLUSION

Among a contemporary cohort of nulliparous women undergoing term labor induction, amniotomy was associated with either lower or similar odds of cesarean delivery and other adverse outcomes, compared with no amniotomy.

A Trial of Hyperimmune Globulin to Prevent Congenital Cytomegalovirus Infection

BACKGROUND

Primary cytomegalovirus (CMV) infection during pregnancy carries a risk of congenital infection and possible severe sequelae. There is no established intervention for preventing congenital CMV infection.

METHODS

In this multicenter, double-blind trial, pregnant women with primary CMV infection diagnosed before 24 weeks' gestation were randomly assigned to receive a monthly infusion of CMV hyperimmune globulin (at a dose of 100 mg per kilogram of body weight) or matching placebo until delivery. The primary outcome was a composite of congenital CMV infection or fetal or neonatal death if CMV testing of the fetus or neonate was not performed.

RESULTS

From 2012 to 2018, a total of 206,082 pregnant women were screened for primary CMV infection before 23 weeks of gestation; of the 712 participants (0.35%) who tested positive, 399 (56%) underwent randomization. The trial was stopped early for futility. Data on the primary outcome were available for 394 participants; a primary outcome event occurred in the fetus or neonate of 46 of 203 women (22.7%) in the group that received hyperimmune globulin and of 37 of 191 women (19.4%) in the placebo group (relative risk, 1.17; 95% confidence interval [CI] 0.80 to 1.72; P = 0.42). Death occurred in 4.9% of fetuses or neonates in the hyperimmune globulin group and in 2.6% in the placebo group (relative risk, 1.88; 95% CI, 0.66 to 5.41), preterm birth occurred in 12.2% and 8.3%, respectively (relative risk, 1.47; 95% CI, 0.81 to 2.67), and birth weight below the 5th percentile occurred in 10.3% and 5.4% (relative risk, 1.92; 95% CI, 0.92 to 3.99). One participant in the hyperimmune globulin group had a severe allergic reaction to the first infusion. Participants who received hyperimmune globulin had a higher incidence of headaches and shaking chills while receiving infusions than participants who received placebo.

CONCLUSIONS

Among pregnant women, administration of CMV hyperimmune globulin starting before 24 weeks' gestation did not result in a lower incidence of a composite of congenital CMV infection or perinatal death than placebo. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the National Center for Advancing Translational Sciences; ClinicalTrials.gov number, NCT01376778.).

Study Protocol for Preventing Early-Onset Pneumonia in Young Children Through Maternal Immunisation: A Multi-Centre Randomised Controlled Trial (PneuMatters)

Background: Preventing and/or reducing acute lower respiratory infections (ALRIs) in young children will lead to substantial short and long-term clinical benefits. While immunisation with pneumococcal conjugate vaccines (PCV) reduces paediatric ALRIs, its efficacy for reducing infant ALRIs following maternal immunisation has not been studied. Compared to other PCVs, the 10-valent pneumococcal-Haemophilus influenzae Protein D conjugate vaccine (PHiD-CV) is unique as it includes target antigens from two common lower airway pathogens, pneumococcal capsular polysaccharides and protein D, which is a conserved H. influenzae outer membrane lipoprotein. Aims: The primary aim of this randomised controlled trial (RCT) is to determine whether vaccinating pregnant women with PHiD-CV (compared to controls) reduces ALRIs in their infants' first year of life. Our secondary aims are to evaluate the impact of maternal PHiD-CV vaccination on different ALRI definitions and, in a subgroup, the infants' nasopharyngeal carriage of pneumococci and H. influenzae, and their immune responses to pneumococcal vaccine type serotypes and protein D. Methods: We are undertaking a parallel, multicentre, superiority RCT (1:1 allocation) at four sites across two countries (Australia, Malaysia). Healthy pregnant Australian First Nation or Malaysian women aged 17-40 years with singleton pregnancies between 27⁺⁶ and 34⁺⁶ weeks gestation are randomly assigned to receive either a single dose of PHiD-CV or usual care. Treatment allocation is concealed. Study outcome assessors are blinded to treatment arms. Our primary outcome is the rate of medically attended ALRIs by 12-months of age. Blood and nasopharyngeal swabs are collected from infants at birth, and at ages 6- and 12-months (in a subset). Our planned sample size (n = 292) provides 88% power (includes 10% anticipated loss to follow-up). Discussion: Results from this RCT potentially leads to prevention of early and recurrent ALRIs and thus preservation of lung health during the infant's vulnerable period when lung growth is maximum. The multicentre nature of our study increases the generalisability of its future findings and is complemented by assessing the microbiological and immunological outcomes in a subset of infants. Clinical Trial Registration: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=374381, identifier: ACTRN12618000150246.

Coronavirus disease 2019 vaccines in pregnancy

As of December 1, 2020, nearly 64 million people have been infected with the severe acute respiratory syndrome coronavirus 2 worldwide with nearly 1.5 million global deaths. The impact of this virus has continued to overwhelm hospital infrastructure and demanded remodeling of healthcare systems. With rising concerns for a third, and possibly the largest, wave of individuals infected with the virus, national leaders are continuing to seek avenues by which we can further limit disease transmission and prevent infection with the use of vaccination. To our knowledge, no clinical trial evaluating vaccines to prevent coronavirus disease 2019 has included pregnant women. In December 2020, it was anticipated that the Food and Drug Administration will approve at least 1 or 2 mRNA-based coronavirus disease 2019 vaccine under the Emergency Use Authorization based on phase 3 clinical trial efficacy data. Both Pfizer and Moderna have manufactured mRNA-based vaccines with 95% and 94.1% efficacy against the severe acute respiratory syndrome coronavirus 2. AstraZeneca has manufactured a vaccine using a viral vector demonstrating early efficacy as well, and this next-generation platform has previously been utilized with the Ebola vaccine and safely administered during pregnancy with an acceptable safety profile. Approval of these vaccines will have a tremendous impact on the ongoing pandemic, yet there remains a lack of data for use of coronavirus disease 2019 vaccine in pregnant women. In this article, we seek to discuss the available data regarding treatment and prevention of coronavirus disease 2019 in pregnancy and address the growing questions regarding how best to approach vaccine access and administration in the pregnant population.

Pregnancy vs. paycheck: a qualitative study of patient's experience with employment during pregnancy at high risk for preterm birth

Background

Pregnant women with a history of preterm birth are at risk for recurrence, often requiring frequent prenatal visits for close monitoring and/or preventive therapies. Employment demands can limit uptake and adherence to recommended monitoring and preterm birth prevention therapies.

Method

We conducted a qualitative descriptive study using in-depth interviews (IDIs) of pregnant women with a history of preterm birth. IDIs were conducted by trained qualitative interviewers following a semi-structured interview guide focused on uncovering barriers and facilitators to initiation of prenatal care, including relevant employment experiences, and soliciting potential interventions to improve prompt prenatal care initiation. The IDIs were analyzed via applied thematic analysis.

Results

We described the interview findings that address women’s employment experiences. The current analysis includes 27 women who are majority self-described as non-Hispanic Black (74%) and publically insured (70%). Participants were employed in a range of professions; food services, childcare and retail were the most common occupations. Participants described multiple ways that being pregnant impacted their earning potential, ranging from voluntary work-hour reduction, involuntary duty hour reductions by employers, truncated promotions, and termination of employment. Participants also shared varying experiences with workplace accommodations to their work environment and job duties based on their pregnancy. Some of these accommodations were initiated by a collaborative employee/employer discussion, others were initiated by the employer’s perception of safe working conditions in pregnancy, and some accommodations were based on medical recommendations. Participants described supportive and unsupportive employer reactions to requests for accommodations.

Conclusions

Our findings provide novel insights into women’s experiences balancing a pregnancy at increased risk for preterm birth with employment obligations. While many women reported positive experiences, the most striking insights came from women who described negative situations that ranged from challenging to potentially unlawful. Many of the findings suggest profound misunderstandings likely exist at the patient, employer and clinical provider level about the laws surrounding employment in pregnancy, safe employment responsibilities during pregnancy, and the range of creative accommodations that often allow for continued workplace productivity even during high risk pregnancy.

Safety and immunogenicity of an investigational maternal trivalent group B streptococcus vaccine in pregnant women and their infants: Results from a randomized placebo-controlled phase II trial

BACKGROUND

This study evaluated the safety and immunogenicity of an investigational trivalent group B streptococcus (GBS) vaccine in US pregnant women, transplacental serotype-specific antibody transfer and persistence in infants, and serotype-specific antibodies in breast milk.

METHODS

This randomized, observer-blind, placebo-controlled trial administered one dose of trivalent GBS vaccine (n = 49) or placebo (n = 26) to healthy pregnant 18-40-year-old women at 24^0/7-34^6/7 weeks' gestation. Women were enrolled from March 2014 to August 2015. Safety follow-up continued through postpartum day 180. Primary immunogenicity objectives were to evaluate serotype Ia/Ib/III-specific immunoglobulin G (IgG) levels in sera from women on day 1 (pre-vaccination), day 31, delivery and postpartum days 42 and 90, and from infants at birth (cord blood), days 42 and 90. Antibody transfer ratios (cord blood/maternal sera at delivery) and serotype-specific secretory immunoglobulin A (sIgA) and IgG in breast milk after delivery and on postpartum days 42 and 90 were evaluated. The planned sample size was not based on statistical assumptions for this descriptive study.

RESULTS

Baseline characteristics were similar between groups. Serious adverse events were reported for 16% of GBS-vaccinated women and 15% of their infants, and 15% of placebo recipients and 12% of their infants; none were fatal or deemed vaccine-related. Serotype-specific IgG geometric mean concentrations (GMCs) were 13-23-fold higher in vaccine vs placebo recipients on day 31 and persisted until postpartum day 90. Median antibody concentrations were substantially higher in women with detectable pre-vaccination antibody concentrations. Antibody transfer ratios in the vaccine group were 0.62-0.82. Infant IgG GMCs and breast milk sIgA GMCs were higher in the vaccine vs the placebo group at all timepoints.

CONCLUSIONS

Maternal immunization with the trivalent GBS vaccine in US women had a favorable safety profile, elicited antibodies that were transplacentally transferred and persisted in infants for a minimum of 3 months.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov, NCT02046148.

Respiratory Syncytial Virus Vaccination during Pregnancy and Effects in Infants

BACKGROUND

Respiratory syncytial virus (RSV) is the dominant cause of severe lower respiratory tract infection in infants, with the most severe cases concentrated among younger infants.

METHODS

Healthy pregnant women, at 28 weeks 0 days through 36 weeks 0 days of gestation, with an expected delivery date near the start of the RSV season, were randomly assigned in an overall ratio of approximately 2:1 to receive a single intramuscular dose of RSV fusion (F) protein nanoparticle vaccine or placebo. Infants were followed for 180 days to assess outcomes related to lower respiratory tract infection and for 364 days to assess safety. The primary end point was RSV-associated, medically significant lower respiratory tract infection up to 90 days of life, and the primary analysis of vaccine efficacy against the primary end point was performed in the per-protocol population of infants (prespecified criterion for success, lower bound of the 97.52% confidence interval [CI] of ≥30%).

RESULTS

A total of 4636 women underwent randomization, and there were 4579 live births. During the first 90 days of life, the percentage of infants with RSV-associated, medically significant lower respiratory tract infection was 1.5% in the vaccine group and 2.4% in the placebo group (vaccine efficacy, 39.4%; 97.52% CI, -1.0 to 63.7; 95% CI, 5.3 to 61.2). The corresponding percentages for RSV-associated lower respiratory tract infection with severe hypoxemia were 0.5% and 1.0% (vaccine efficacy, 48.3%; 95% CI, -8.2 to 75.3), and the percentages for hospitalization for RSV-associated lower respiratory tract infection were 2.1% and 3.7% (vaccine efficacy, 44.4%; 95% CI, 19.6 to 61.5). Local injection-site reactions among the women were more common with vaccine than with placebo (40.7% vs. 9.9%), but the percentages of participants who had other adverse events were similar in the two groups.

CONCLUSIONS

RSV F protein nanoparticle vaccination in pregnant women did not meet the prespecified success criterion for efficacy against RSV-associated, medically significant lower respiratory tract infection in infants up to 90 days of life. The suggestion of a possible benefit with respect to other end-point events involving RSV-associated respiratory disease in infants warrants further study. (Funded by Novavax and the Bill and Melinda Gates Foundation; ClinicalTrials.gov NCT02624947.).

Safety and immunogenicity of three seasonal inactivated influenza vaccines among pregnant women and antibody persistence in their infants

OBJECTIVE

Inactivated influenza virus vaccines (IIVs) are recommended for all pregnant women in the United States. We conducted a prospective, randomized, double blind study of three licensed seasonal trivalent IIVs (IIV3s) to assess their safety and immunogenicity in pregnant women and determine the level and persistence of passively transferred maternal antibody in infants.

STUDY DESIGN

139 pregnant women ages 18-39 years and 14-33 weeks' gestation, and 44 non-pregnant women, were randomized 1:1:1 to receive a single intramuscular dose of one of three licensed IIV3s (Agriflu®, Fluzone®, or Fluarix®) prior to the 2010-2011 influenza season. Reactogenicity, adverse events (AEs) and pregnancy outcomes were documented. Serum samples for hemagglutination inhibition (HAI) and neutralization antibody assays were collected prior to and 28 and 180 days after immunization. Maternal sera and cord blood were collected at the time of delivery and sera were obtained from 44 infants at 6 weeks of age.

RESULTS

Pregnant and non-pregnant women experienced similar frequency of injection site (92% and 86%, respectively) and systemic (95% and 87%, respectively) reactions, the majority of which were mild. There were no vaccine-associated maternal or infant serious AEs. Antibody responses to the three vaccine antigens were not different between pregnant and non-pregnant women. The ratios of cord blood (infant) to maternal HAI antibody titers at delivery ranged between 1.1 and 1.7 for each of the vaccine antigens. Influenza antibody concentrations in infants were 70-40% of the birth titer by 6 weeks of age.

CONCLUSIONS

The three IIV3s were well tolerated in pregnant women. Antibody responses were comparable in pregnant and non-pregnant women, and after second or third trimester vaccination. Transplacental transfer of maternal antibodies to the infant was efficient. However, antibody titers decline rapidly in the first 6 weeks of life.

Efficacy of a Texting Program to Promote Cessation Among Pregnant Smokers: A Randomized Control Trial

INTRODUCTION

Smoking during pregnancy poses serious risks to baby and mother. Few disseminable programs exist to help pregnant women quit or reduce their smoking. We hypothesized that an SMS text-delivered scheduled gradual reduction (SGR) program plus support texts would outperform SMS support messages alone.

METHODS

We recruited 314 pregnant women from 14 prenatal clinics. Half of the women received theory-based support messages throughout their pregnancy to promote cessation and prevent relapse. The other half received the support messages plus alert texts that gradually reduced their smoking more than 3-5 weeks. We conducted surveys at baseline, end of pregnancy, and 3 months postpartum. Our primary outcome was biochemically validated 7-day point prevalence abstinence at late pregnancy. Our secondary outcome was reduction in cigarettes per day.

RESULTS

Adherence to the SGR was adequate with 70% responding to alert texts to smoke within 60 minutes. Women in both arms quit smoking at the same rate (9%-12%). Women also significantly reduced their smoking from baseline to the end of pregnancy from nine cigarettes to four; we found no arm differences in reduction.

CONCLUSIONS

Support text messages alone produced significant quit rates above naturally occurring quitting. SGR did not add significantly to helping women quit or reduce. Sending support messages can reach many women and is low-cost. More obstetric providers might consider having patients who smoke sign up for free texting programs to help them quit.

IMPLICATIONS

A disseminable texting program helped some pregnant women quit smoking.Clinical Trial Registration number: NCT01995097.

Efficiency of placental transfer of vaccine-elicited antibodies relative to prenatal Tdap vaccination status

Administration of vaccines during pregnancy provides maternal protection against infectious diseases. This protection is extended to their infants during the first months of life, as pathogen-specific antibodies formed in response to maternal vaccination are transferred across the placenta to the fetus. Notably, Tdap (tetanus-diphtheria-acellular pertussis) vaccination booster is routinely administered to pregnant women both to prevent neonatal tetanus and to ensure that infants have protective levels of pertussis antibodies until they are able to establish their own vaccine-induced levels. Whether infant protection through maternal immunization is merely due to an increase in maternal antibody levels or whether maternal immunization enhances the transfer of vaccine-specific antibodies is unclear. Moreover, the potential impact of prenatal vaccinations on the transplacental transfer of other antibodies, such as antibodies raised as a result of infections or other vaccines administered prior to pregnancy, has not been studied. The goal of this study was to define the impact of maternal vaccination on IgG transplacental transfer efficiency. We analyzed antigen-specific antibody populations and IgG subclass distribution in maternal and cord blood samples from 58 mother-infant pairs. All women received the seasonal inactivated influenza vaccine during pregnancy and 25 women received the Tdap vaccine during the second or third trimester of gestation. Prenatal Tdap vaccination did not impact the efficiency of IgG transplacental transfer; however, it was associated with higher maternal and infant vaccine-elicited Tdap-specific antibody levels, and with a higher proportion of infants with protective levels of antibodies, especially against diphtheria. There was also no difference in the IgG transplacental transfer rate of antibodies against non-Tdap vaccines between the two groups of women. Our results confirm previous reports demonstrating the benefits of prenatal Tdap immunization and indicate that this strategy does not impede the transplacental transfer of other antibodies that are also important for infant protection.

Safety and Immunogenicity of a Respiratory Syncytial Virus Fusion (F) Protein Nanoparticle Vaccine in Healthy Third-Trimester Pregnant Women and Their Infants

BACKGROUND

Respiratory syncytial virus (RSV) is the leading cause of infant lower respiratory tract disease and hospitalization worldwide.

METHODS

Safety and immunogenicity of RSV fusion (F) protein nanoparticle vaccine or placebo were evaluated in 50 healthy third-trimester pregnant women. Assessments included vaccine tolerability and safety in women and infants, and RSV-specific antibody measures in women before and after vaccination, at delivery and post partum.

RESULTS

The vaccine was well tolerated; no meaningful differences in pregnancy or infant outcomes were observed between study groups. RSV-specific antibody levels increased significantly among vaccine recipients, including responses competitive with well-described monoclonal antibodies specific for multiple RSV neutralizing epitopes. No significant antibody increase was seen among placebo recipients, although a shallow upward trend across the RSV season was noted. Transplacental antibody transfer was 90%-120% across assays for infants of vaccinated women. Women with an interval of ≥30 days between vaccination and delivery demonstrated higher placental antibody transfer rates than women with an interval <30 days. Half-lives of RSV-specific antibodies in infants approximated 40 days. There was no evidence of severe RSV disease in infants of vaccinated mothers.

CONCLUSIONS

Data from this phase 2 study support a maternal immunization strategy to protect infants from RSV disease.

CLINICAL TRIALS REGISTRATION

NCT02247726.

Hydroxychloroquine in Patients with Rheumatic Disease Complicated by COVID-19: Clarifying Target Exposures and the Need for Clinical Trials

OBJECTIVE

To characterize hydroxychloroquine (HCQ) exposure in patients with rheumatic disease receiving longterm HCQ compared to target concentrations with reported antiviral activity against the coronavirus disease 2019 caused by SARS-CoV-2 (COVID-19).

METHODS

We evaluated total HCQ concentrations in serum and plasma from published literature values, frozen serum samples from a pediatric systemic lupus erythematosus trial, and simulated concentrations using a published pharmacokinetic model during pregnancy. For each source, we compared observed or predicted HCQ concentrations to target concentrations with reported antiviral activity against SARS-CoV-2.

RESULTS

The average total serum/plasma HCQ concentrations were below the lowest SARS-CoV-2 target of 0.48 mg/l in all studies. Assuming the highest antiviral target exposure (total plasma concentration of 4.1 mg/l), all studies had about one-tenth the necessary concentration for in vitro viral inhibition. Pharmacokinetic model simulations confirmed that pregnant adults receiving common dosing for rheumatic diseases did not achieve target exposures; however, the models predict that a dosage of 600 mg once a day during pregnancy would obtain the lowest median target exposure for most patients after the first dose.

CONCLUSION

We found that the average patient receiving treatment with HCQ for rheumatic diseases, including children and non-pregnant/pregnant adults, are unlikely to achieve total serum or plasma concentrations shown to inhibit SARS-CoV-2 in vitro. Nevertheless, patients receiving HCQ long term may have tissue concentrations far exceeding that of serum/plasma. Because the therapeutic window for HCQ in the setting of SARS-CoV-2 is unknown, well-designed clinical trials that include patients with rheumatic disease are urgently needed to characterize the efficacy, safety, and target exposures for HCQ.

OB/GYN Providers' Knowledge of Racial and Ethnic Reproductive Health Disparities

OBJECTIVE

This study explores OB/GYN providers' knowledge about published health and healthcare disparities in women's reproductive health.

METHOD

We collected demographic and health disparities knowledge information from OB/GYN providers who were members of ACOG District IV using an online survey (n = 483). We examined differences across groups using statistical tests and regression analyses in a structural equation modeling approach.

RESULTS

Receiving disparities education was positively associated with higher self-reported disparities knowledge and disparities quiz performance (p < 0.05). African American/Black providers had higher quiz scores than their white counterparts, and providers varied in their levels of disparities knowledge across practice settings (p < 0.05).

CONCLUSIONS

Differences in levels of knowledge of racial/ethnic disparities in health and healthcare outcomes among OB/GYN providers varied across race/ethnicity, practice context, and whether providers had received formal disparities education. Future research should explore these differences at a population level and develop interventions to improve health disparities education among OB/GYN providers.

Health resource utilization of labor induction versus expectant management

BACKGROUND

Although induction of labor of low-risk nulliparous women at 39 weeks reduces the risk of cesarean delivery compared with expectant management, concern regarding more frequent use of labor induction remains, given that this intervention historically has been thought to incur greater resource utilization.

OBJECTIVE

The objective of the study was to determine whether planned elective labor induction at 39 weeks among low-risk nulliparous women, compared with expectant management, was associated with differences in health care resource utilization from the time of randomization through 8 weeks postpartum.

STUDY DESIGN

This is a planned secondary analysis of a multicenter randomized trial in which low-risk nulliparous women were assigned to induction of labor at 39 weeks or expectant management. We assessed resource utilization after randomization in 3 time periods: antepartum, delivery admission, and discharge through 8 weeks postpartum.

RESULTS

Of 6096 women with data available, those in the induction of labor group (n = 3059) were significantly less likely in the antepartum period after randomization to have at least 1 ambulatory visit for routine prenatal care (32.4% vs 68.4%), unanticipated care (0.5% vs 2.6%), or urgent care (16.2% vs 44.3%), or at least 1 antepartum hospitalization (0.8% vs 2.2%, P < .001 for all). They also had fewer tests (eg, sonograms, blood tests) and treatments (eg, antibiotics, intravenous hydration) prior to delivery. During the delivery admission, women in the induction of labor group spent a longer time in labor and delivery (median, 0.83 vs 0.57 days), but both women (P = .002) and their neonates (P < .001) had shorter postpartum stays. Women and neonates in both groups had similar frequencies of postpartum urgent care and hospital readmissions (P > .05 for all).

CONCLUSION

Women randomized to induction of labor had longer durations in labor and delivery but significantly fewer antepartum visits, tests, and treatments and shorter maternal and neonatal hospital durations after delivery. These results demonstrate that the health outcome advantages associated with induction of labor are gained without incurring uniformly greater health care resource use.

Association Between Features of Spontaneous Late Preterm Labor and Late Preterm Birth

OBJECTIVE

This study aimed to evaluate the association between clinical and examination features at admission and late preterm birth.

STUDY DESIGN

The present study is a secondary analysis of a randomized trial of singleton pregnancies at 340/7 to 365/7 weeks' gestation. We included women in spontaneous preterm labor with intact membranes and compared them by gestational age at delivery (preterm vs. term). We calculated a statistical cut-point optimizing the sensitivity and specificity of initial cervical dilation and effacement at predicting preterm birth and used multivariable regression to identify factors associated with late preterm delivery.

RESULTS

A total of 431 out of 732 (59%) women delivered preterm. Cervical dilation ≥ 4 cm was 60% sensitive and 68% specific for late preterm birth. Cervical effacement ≥ 75% was 59% sensitive and 65% specific for late preterm birth. Earlier gestational age at randomization, nulliparity, and fetal malpresentation were associated with late preterm birth. The final regression model including clinical and examination features significantly improved late preterm birth prediction (81% sensitivity, 48% specificity, area under the curve = 0.72, 95% confidence interval [CI]: 0.68-0.75, and p-value < 0.01).

CONCLUSION

Four in 10 women in late-preterm labor subsequently delivered at term. Combination of examination and clinical features (including parity and gestational age) improved late-preterm birth prediction.