Premature rupture of the membranes between 20 and 25 weeks' gestation: role of amniotic fluid volume in perinatal outcome

Outcomes of pregnancies with preterm premature rupture of membranes occurring before 24 weeks of gestation: An 11-year observational study

OBJECTIVE

This study describes the fetal and neonatal outcomes and their predictive factors in pregnancies with preterm premature rupture of membranes (PPROM) before 24 weeks of gestation.

METHODS

A retrospective study was conducted using the patient database of a tertiary university hospital in Lyon, France. All of the medical data of women diagnosed with PPROM before 24 weeks of gestation from 2008 to 2018 were extracted. R software was used for descriptive and analytical statistics.

RESULTS

The study included 78 women. Mean gestational age (GA) at PPROM was 19.6 weeks (13.1 to 23.9 weeks). Fifteen (19.2%) pregnancies were terminated, 37 (47.4%) resulted in intrauterine fetal death (IUFD), and 26 (33.3%) children were born alive at an average of 26.9 weeks of gestation. Fourteen children survived and 12 died after birth; 50% of survivors had pulmonary hypoplasia. Within 7 days after PPROM, 46% of IUFD occurred and 36% of pregnancies ended. PPROM before 20 weeks of gestation and chorioamnionitis are statistically associated with IUFD, whereas a latency period of more than 2 weeks is statistically related to live birth.

CONCLUSION

PPROM before 24 weeks of gestation is associated with a high rate of IUFD, preterm birth, and postpartum mortality.

Maternal, perinatal and childhood outcomes of the PPROMEXIL-III cohort: Pregnancies complicated by previable prelabor rupture of membranes

OBJECTIVE

Perinatal mortality after previable prelabor rupture of membranes (previable PROM) might be underestimated as most studies exclude patients with poor prognosis, or solely include patients in tertiary-care centers. We aimed to report perinatal, neonatal and long-term outcomes in a consecutive series of women with pregnancies complicated by previable PROM.

STUDY DESIGN

We conducted a prospective cohort study including women with singleton pregnancies and previable PROM ≤ 23⁺⁶ weeks gestational age (GA) from one tertiary hospital and eight affiliated secondary hospitals in the region of Amsterdam, the Netherlands (June 2012 until January 2016, PPROMEXIL-III cohort). Exclusion criteria were signs of active labor before onset of PROM or fetal structural anomalies visible at ultrasound. We assessed perinatal mortality. Furthermore, outcomes were maternal, perinatal, neonatal and long-term child characteristics.

RESULTS

We included 98 pregnancies with previable PROM. Twelve women (12.2%) opted for termination of pregnancy, resulting in 86 pregnancies included in further analyses. Median GA at PROM was 20⁺² weeks (interquartile range (IQR) 17⁺⁶-22⁺⁰). Median GA at delivery was 22⁺⁶ weeks (IQR 20⁺¹-26⁺⁴). Delivery within 1 week occurred in 38.4% of women and 60.4% delivered before 24 weeks GA (viability). Perinatal mortality occurred in 73.3% of pregnancies. 23/33 (69.7%) live-born neonates survived to discharge, representing 26.7% of total. None of the children died after discharge. Developmental data at two and/or five years of age was available for 13/23 children (i.e. all children born before 32 weeks of gestation), with 69.2% of children reporting a normal neurodevelopment. However, more than half of children reported respiratory problems.

CONCLUSION

In women with previable PROM perinatal mortality was 73.3%, with a normal neurodevelopment in 69.2% of surviving children with follow-up data. Due to broad inclusion criteria, this cohort represents a population more generalizable to daily practice as compared to previous studies.

Neonatal Outcomes according to the Latent Period from Membrane Rupture to Delivery among Extremely Preterm Infants Exposed to Preterm Premature Rupture of Membrane: a Nationwide Cohort Study

BACKGROUND

In accordance with the guidelines for the expectant management of women exposed to previable preterm premature rupture of membrane, we compared neonatal outcomes according to the latent period from membrane rupture to delivery among extremely preterm infants exposed to maternal preterm premature rupture of membrane using the Korean Neonatal Network database.

METHODS

Of the 3,305 extremely preterm infants born at 23-27 weeks' gestation between 2014 and 2017 who were registered in the Korean Neonatal Network, 1,464 infants were born to pregnant women who were exposed to preterm premature rupture of membrane. The short latency group was defined as infants born with a latent period between membrane rupture and delivery < 7 days (n = 450), whereas the prolonged latency group was defined as infants born with a latent period of ≥ 7 days (n = 434). Using well-established risk factors for adverse short-term outcomes, multivariate logistic regression analysis was performed to assess a prolonged latent period in preterm premature rupture of membrane as an independent risk factor for neonatal outcomes in extremely preterm infants exposed to preterm premature rupture of membrane.

RESULTS

The mean gestational age at membrane rupture in the prolonged latency group was significantly lower than that in the short latency group (22.7 ± 2.5 vs. 25.4 ± 1.3 weeks, P < 0.001). Nevertheless, the mean gestational age at delivery and birth weight were not significantly different between the two groups. The incidence of oligohydramnios and histologic chorioamnionitis in the prolonged latency group was significantly higher than that in the short latency group (38.7 [155/401] vs. 26.1 [105/403], 69.8 [270/384] vs. 61.0 [242/397], respectively, P < 0.05). The survival rate in the prolonged latency group did not differ from that in the short latency group (71.2 [309/434] vs. 73.3 [330/450], P = 0.478). Although the prolonged latency group was not associated with mortality during hospitalization in the multivariate logistic regression analysis, the prolonged latency group's early pulmonary hypertension and bronchopulmonary dysplasia rates were increased by 1.8 and 1.5 times, respectively.

CONCLUSION

A prolonged latent period of 7 days or more does not affect the survival rate but increases the risk of bronchopulmonary dysplasia occurrence among extremely preterm infants who are exposed to maternal preterm premature rupture of membrane.

Predictors of Short Latency Period Exceeding 48 h after Preterm Premature Rupture of Membranes

Background: Preterm premature rupture of membranes (PPROM) is a complication responsible for a third of preterm births. Clinical management is initially hospital based, but homecare management is possible if patients are clinically stable 48 h after PPROM. This study set out to determine factors that are predictive of short latency (delivery ≤ 7 days) exceeding 48 h after PPROM, enabling estimation of the prevalence of maternal and neonatal complications and comparison of maternal and fetal outcomes between inpatient and outpatient management. Method: This was a monocentric retrospective study conducted between 1 January 2010 and 28 February 2017 on all patients experiencing PPROM at 24 to 34 weeks + 6 days and who gave birth after 48 h. Maternal, obstetric, fetal, and neonatal variables were included in the data collected. The primary endpoint was latency, defined as the number of days between rupture of membranes and delivery. Results: 170 consecutive patients were analyzed. Short latency could be predicted by the need for tocolysis, a cervical length less than 25 mm at admission and the existence of anamnios. Outpatient follow-up was not found to lead to increased maternal morbidity or neonatal mortality. Conclusion: Our study highlights predictive factors of short latency exceeding 48 h after PPROM. Knowledge of these factors may provide justification for outpatient monitoring of patients presenting with a long cervix, absence of need for tocolysis and persistence of amniotic fluid and, thus, no risk factors after 48 h of admission.

Prelabor Rupture of Membranes: ACOG Practice Bulletin, Number 217

Preterm birth occurs in approximately 10% of all births in the United States and is a major contributor to perinatal morbidity and mortality (). Prelabor rupture of membranes (PROM) that occurs preterm complicates approximately 2-3% of all pregnancies in the United States, representing a significant proportion of preterm births, whereas term PROM occurs in approximately 8% of pregnancies (). The optimal approach to assessment and treatment of women with term and preterm PROM remains challenging. Management decisions depend on gestational age and evaluation of the relative risks of delivery versus the risks (eg, infection, abruptio placentae, and umbilical cord accident) of expectant management when pregnancy is allowed to progress to a later gestational age. The purpose of this document is to review the current understanding of this condition and to provide management guidelines that have been validated by appropriately conducted outcome-based research when available. Additional guidelines on the basis of consensus and expert opinion also are presented. This Practice Bulletin is updated to include information about diagnosis of PROM, expectant management of PROM at term, and timing of delivery for patients with preterm PROM between 34 0/7 weeks of gestation and 36 6/7 weeks of gestation.

Progestins Inhibit Interleukin-1β-Induced Matrix Metalloproteinase 1 and Interleukin 8 Expression via the Glucocorticoid Receptor in Primary Human Amnion Mesenchymal Cells

Preterm premature rupture of membranes is a leading cause of preterm births. Cytokine induced matrix metalloproteinase1 and interleukin 8 production from amnion mesenchymal cells may contribute to fetal membrane weakening and rupture. Progestins inhibit inflammation induced fetal membrane weakening but their effect on the inflammatory response of amnion mesenchymal cells is unknown. This study was designed to determine the role of progesterone receptor membrane component 1 and the glucocorticoid receptor in mediating the effects of progestins on interleukin-1β induced matrix metalloproteinase 1 and interleukin-8 expression in human amnion mesenchymal cells. Primary amnion mesenchymal cells harvested from human fetal membranes were passaged once and treated with vehicle, progesterone or medroxyprogesterone acetate at 10-6 M for 1 h followed by stimulation with interleukin-1β at 1 ng/ml for 24 h. Medroxyprogesterone acetate but not progesterone inhibited interleukin-1β-induced interlukin-8 and matrix metalloproteinase 1 mRNA expression. In subsequent dose response studies, medroxyprogesterone acetate, but not progesterone, at doses of 10-6-10-8 M inhibited interleukin-1β induced interleukin-8 and matrix metalloproteinase 1 mRNA expression. We further demonstrated that inhibition of glucocorticoid receptor expression, but not progesterone receptor membrane component 1 knockdown with small interfering RNA transfection, resulted in a reversal in medroxyprogesterone acetate's (10-7 M) inhibition of interleukin-1β- induced matrix metalloproteinase 1 mRNA expression and interleukin-8 mRNA expression and protein expression. Our findings demonstrate that medroxyprogesterone acetate exerts its anti-inflammatory effect primarily through the glucocorticoid receptor in human amnion mesenchymal cells. Modulation of glucocorticoid receptor signaling pathways maybe a useful therapeutic strategy for preventing inflammation induced fetal membrane weakening leading to preterm premature rupture of membranes.

Case report and literature review of management of preterm prelabour rupture of membranes before fetal viability

Preterm prelabour rupture of membranes (PPROM) complicates up to 3% of pregnancy and is responsible for one third of preterm deliveries. PPROM at extremely preterm gestations (<24 weeks) affects 0.4% of pregnancies and is associated with low neonatal survival rates, high rate of neonatal complications in survivors, and carries major risk of maternal morbidity and mortality. We present a rare case of pregnancy complicated by PPROM at 14 weeks which resulted in a term delivery and a good neonatal outcome.

Amniotic fluid volume at presentation with early preterm prelabor rupture of membranes and association with severe neonatal respiratory morbidity

OBJECTIVE

Amniotic fluid volume (AFV) plays an important role in early fetal lung development, and oligohydramnios in early pregnancy is associated with pulmonary hypoplasia. The aim of this study was to evaluate the association between AFV at the time of presentation with early preterm prelabor rupture of membranes (PPROM) and severe neonatal respiratory morbidity and other adverse pregnancy outcomes.

METHODS

This was a retrospective study of all women with a singleton pregnancy, admitted to a single tertiary referral center between 2004 and 2014, for expectant management of PPROM at 20 + 0 to 28 + 6 weeks' gestation. The primary exposure was AFV at presentation, classified according to sonographic maximum vertical pocket (MVP) as: normal AFV (> 2 cm), oligohydramnios (≤ 2 cm and > 1 cm) or severe oligohydramnios (≤ 1 cm). The primary outcome was a composite variable of severe respiratory morbidity, defined as either of the following: (1) need for respiratory support in the form of mechanical ventilation using an endotracheal tube for ≥ 72 h and need for surfactant; or (2) bronchopulmonary dysplasia, defined as requirement for oxygen at postmenstrual age of 36 weeks or at the time of transfer to a Level-II facility. Adjusted odds ratios (aOR) and 95% CI for the primary and secondary outcomes were calculated for each AFV-at-presentation group (using normal AFV as the reference), adjusting for gestational age (GA) at PPROM, latency period, birth weight, mode of delivery and chorioamnionitis.

RESULTS

In total, 580 women were included, of whom 304 (52.4%) had normal AFV, 161 (27.8%) had oligohydramnios and 115 (19.8%) had severe oligohydramnios at presentation. The rates of severe respiratory morbidity were 16.1%, 26.7% and 45.2%, respectively. Compared with normal AFV at presentation, oligohydramnios (aOR, 3.27; 95% CI, 1.84-5.84) and severe oligohydramnios (aOR, 4.11; 95% CI, 2.26-7.56) at presentation were associated independently with severe respiratory morbidity. Other variables that were associated independently with the primary outcome were GA at PPROM (aOR, 0.54; 95% CI, 0.43-0.69), latency period (aOR, 0.94; 95% CI, 0.91-0.98) and Cesarean delivery (aOR, 2.01; 95% CI, 1.21-3.32).

CONCLUSIONS

In women with early PPROM, AFV at presentation, as assessed by the MVP on ultrasound examination, is associated independently with severe neonatal respiratory morbidity. This information may be taken into consideration when counseling women with early PPROM regarding neonatal outcome and management options. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

[Antenatal management in case of preterm premature rupture of membranes before fetal viability: CNGOF Preterm Premature Rupture of Membranes Guidelines]

OBJECTIVES

To evaluate the maternal, perinatal and long-term prognosis in the event of previable premature rupture of the membranes (PROM) and to specify the interventions likely to reduce the risks and improve the prognosis.

METHODS

The PubMed database, the Cochrane Library and the recommendations from the French and foreign obstetrical societies or colleges have been consulted.

RESULTS

Previable PROM is a rare event whose frequency varies from 0.3 to 1% according to estimates (NP4). When occurring as a complication of amniocentesis, the prognosis is generally better than when spontaneous (NP3). Between 23 and 39% of women will deliver in the week following PROM and nearly 40% of women will not have given birth 2 weeks after (NP3). The frequency of medical termination of pregnancy varies greatly according to the studies (NP4), as does that of fetal death (NP4). Hospital survival and survival rates without major morbidity as a proportion of conservatively treated patients range from 17-55% and 26-63%, respectively (NP4). Neonatal prognosis is largely dominated by prematurity and its complications (NP3). The frequency of maternal sepsis varies from 0.8 to 4.8% in the most recent studies (NP4). Only one case of maternal death is reported, although 3 cases were identified in France between 2007 and 2012 (NP3). Information is a major component of the care to be provided to women and their partners (Professional consensus). An initial period of hospitalization may be proposed after previable PROM (Professional consensus). Thereafter, there is no argument to recommend hospital management rather than extra-hospital management when there is no argument in favour of intrauterine infection (Professional consensus). An evaluation of the amount of amniotic fluid by ultrasound may be proposed at the initial consultation and after a period of 7 to 14 days if pregnancy continues (Professional consensus). Prophylactic antibiotic treatment is recommended as soon as PROM is diagnosed (Professional consensus). The gestational age at which corticosteroid therapy may be proposed will depend on the thresholds selected for neonatal resuscitation care. In particular, it will take into account parental positioning (Professional consensus). From the time of the decision to perform neonatal resuscitation until the gestational age of 32 weeks, it is recommended to administer MgSO₄ to the woman whose delivery is imminent (Grade A). Tocolysis is not recommended in this context (Professional consensus). In certain situations, meeting strictly the conditions mentioned by the CSP article L. 2213-1, a maternal request for medical interruption of pregnancy may be discussed.

CONCLUSION

The levels of evidence of scientific work on the management of previable PROM are low, therefore, most of the recommendations proposed here are based on professional agreement by "reasonable" extension of recommendations valid for later gestational ages.

Preterm delivery after fetoscopic laser surgery for twin-twin transfusion syndrome: etiology and risk factors

OBJECTIVE

Preterm delivery after fetoscopic laser surgery (FLS) for twin-twin transfusion syndrome (TTTS) is a major complication. The causative factors leading to preterm delivery continue to be elusive and a better understanding of the risk factors could reduce complications. The objective of this study was to determine the etiology of preterm delivery after FLS for TTTS and its associated risk factors.

METHODS

This was a secondary analysis of a prospective study of 203 patients with TTTS who underwent FLS at a single center between September 2011 and December 2014. Preoperative, operative, postoperative, delivery and neonatal data were reviewed. Preterm delivery was categorized according to etiology into three groups: spontaneous (SPT), indicated (IND) and elective (ELC). Comparisons between groups were performed by ANOVA. Kaplan-Meier survival analysis was performed to compare the procedure-to-delivery interval between groups. To identify risk factors for preterm delivery, logistic regression, with calculation of relative risks (RR), was performed, with P < 0.05 considered statistically significant.

RESULTS

Mean gestational age at time of FLS was 20.6 ± 2.4 weeks and mean gestational age at delivery was 30.9 ± 4.7 weeks. Iatrogenic preterm prelabor rupture of membranes (iPPROM) occurred in 39% of cases. SPT preterm delivery occurred in 97 (48%) patients, IND preterm delivery in 65 (32%) and ELC preterm delivery in 41 (20%). In the IND group, 30 (46%) patients delivered for fetal indications, 31 (48%) for maternal indications and four (6%) for combined fetal and maternal indications. The overall chorioamnionitis rate was 6.4%; of these, nine (9%) were in the SPT group and four (6%) were in the IND group, with no case occurring in the ELC group. There was a significant difference in procedure-to-delivery interval between groups (P < 0.0001). Using variables from the ELC group as a baseline, significant risk factors for SPT preterm delivery were iPPROM (RR, 16.2 (95% CI, 4.5-57.7)), preoperative cervical length (RR, 0.96 (95% CI, 0.92-0.998)) and number of anastomoses (RR, 1.14 (95% CI, 1.02-1.27)). Significant risk factors for IND preterm delivery were iPPROM (RR, 9.6 (95% CI, 2.6-35.0)) and number of ablated anastomoses (RR, 1.13 (95% CI, 1.02-1.30)).

CONCLUSION

iPPROM and an increased number of ablated placental anastomoses were associated independently with SPT and IND preterm deliveries. A shorter preoperative cervical length was associated with SPT preterm delivery. Strategies to prevent iPPROM and for management of cervical length shortening are needed urgently in these pregnancies. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Maternal and neonatal outcomes following expectant management of preterm prelabour rupture of membranes before viability

AIM

To assess the contemporary maternal and neonatal outcomes following expectant management of preterm premature rupture of membranes (PPROM) prior to 24 weeks' gestation and to identify prognostic indicators of this morbid presentation.

METHODS

We performed a systematic review in the Pubmed and EMBASE databases to identify the primary (perinatal mortality, severe neonatal morbidity and serious maternal morbidity) and secondary (neonatal survival and morbidity) outcomes following expectant management of previable PPROM.

RESULTS

Mean latency between PPROM and delivery ranged between 20 and 43 days. Women with PPROM <24 weeks had an overall live birth rate of 63.6% and a survival-to-discharge rate of 44.9%. The common neonatal morbidities were respiratory distress syndrome, bronchopulmonary dysplasia and sepsis. The majority of neonatal deaths within 24 h post birth were associated with pulmonary hypoplasia, severe intraventricular haemorrhage and neonatal sepsis. The common maternal outcomes were chorioamnionitis and caesarean sections. The major predictors of neonatal survival were later gestational age at PPROM, adequate residual amniotic fluid levels, C-reactive protein <1 mg/dL within 24 h of admission and PPROM after invasive procedures.

CONCLUSION

Pregnancy latency and neonatal survival following previable PPROM has improved in recent years, although neonatal morbidity remains unchanged despite recent advances in obstetric and neonatal care. There is heterogeneity in management practices across centres worldwide.

Sterile and microbial-associated intra-amniotic inflammation in preterm prelabor rupture of membranes

OBJECTIVE

The objectives of this study were to: (1) determine the amniotic fluid (AF) microbiology of patients with preterm prelabor rupture of membranes (PROM); and (2) examine the relationship between intra-amniotic inflammation with and without microorganisms (sterile inflammation) and adverse pregnancy outcomes in patients with preterm PROM.

METHODS

AF samples obtained from 59 women with preterm PROM were analyzed using cultivation techniques (for aerobic and anaerobic bacteria as well as genital mycoplasmas) and with broad-range polymerase chain reaction coupled with electrospray ionization mass spectrometry (PCR/ESI-MS). AF concentration of interleukin-6 (IL-6) was determined using ELISA. Results of both tests were correlated with AF IL-6 concentrations and the occurrence of adverse obstetrical/perinatal outcomes.

RESULTS

(1) PCR/ESI-MS, AF culture, and the combination of these two tests each identified microorganisms in 36% (21/59), 24% (14/59) and 41% (24/59) of women with preterm PROM, respectively; (2) the most frequent microorganisms found in the amniotic cavity were Sneathia species and Ureaplasma urealyticum; (3) the frequency of microbial-associated and sterile intra-amniotic inflammation was overall similar [ 29% (17/59)]: however, the prevalence of each differed according to the gestational age when PROM occurred; (4) the earlier the gestational age at preterm PROM, the higher the frequency of both microbial-associated and sterile intra-amniotic inflammation; (5) the intensity of the intra-amniotic inflammatory response against microorganisms is stronger when preterm PROM occurs early in pregnancy; and (6) the frequency of acute placental inflammation (histologic chorioamnionitis and/or funisitis) was significantly higher in patients with microbial-associated intra-amniotic inflammation than in those without intra-amniotic inflammation [93.3% (14/15) versus 38% (6/16); p = 0.001].

CONCLUSIONS

(1) The frequency of microorganisms in preterm PROM is 40% using both cultivation techniques and PCR/ESI-MS; (2) PCR/ESI-MS identified microorganisms in the AF of 50% more women with preterm PROM than AF culture; and (3) sterile intra-amniotic inflammation was present in 29% of these patients, and it was as or more common than microbial-associated intra-amniotic inflammation among those presenting after, but not before, 24 weeks of gestation.

Severe midtrimester oligohydramnios: treatment strategies

PURPOSE OF REVIEW

Nearly 1% of pregnancies are affected by some type of midtrimester oligohydramnios. Evidence is currently accumulating that suggests the better efficacy of the new therapeutic procedures relative to conventional management. This review summarizes the available evidence.

RECENT FINDINGS

The prolongation of the period between the diagnosis of oligohydramnios and delivery following amnioinfusion and amniopatch techniques appears to be strongly associated with the gestational age and whether the situation was based on rupture of the membranes or not. Case series reveal that amnioinfusion significantly improves the perinatal outcome and prolongs the pregnancy in severe second-trimester oligohydramnios in both idiopathic cases and those involving rupture of the amniotic membranes [preterm prelabor rupture of the membranes (PPROM)]. There is clear evidence of a lower frequency of perinatal complications and successfully prolonged gestation in iatrogenic PPROM after the amniopatch technique relative to population controls.

SUMMARY

Identification of potentially modifiable risk factors for the successful prolongation of pregnancy complicated with midtrimester oligohydramnios, and previable PPROM is needed for the improvement of treatment strategies and prognosis. Randomized trials are needed to determine whether amniotic fluid-replenishing strategies can improve pregnancy outcomes.

Amnioinfusion in very early preterm prelabor rupture of membranes (AMIPROM): pregnancy, neonatal and maternal outcomes in a randomized controlled pilot study

OBJECTIVE

To assess short- and long-term outcomes of pregnant women with very early rupture of membranes randomized to serial amnioinfusion or expectant management, and to collect data to inform a larger, more definitive clinical trial.

METHODS

This was a prospective non-blinded randomized controlled trial with randomization stratified for pregnancies in which the membranes ruptured between 16 + 0 and 19 + 6 weeks' gestation and 20 + 0 and 23 + 6 weeks' gestation to minimize the risk of random imbalance in gestational age distribution between randomized groups. Intention-to-treat analysis was used. The study was conducted in four UK hospital-based fetal medicine units (Liverpool Women's NHS Trust, St Mary's Hospital Manchester, Birmingham Women's NHS Foundation Trust and Wirral University Hospitals Trust). The participants were women with confirmed preterm prelabor rupture of membranes at 16 + 0 to 24 + 0 weeks' gestation. Women with multiple pregnancy, fetal abnormality or obstetric indication for immediate delivery were excluded. Participants were randomly allocated to either serial weekly transabdominal amnioinfusions if the deepest pool of amniotic fluid was < 2 cm or expectant management until 37 weeks' gestation. Short-term maternal, pregnancy and neonatal and long-term outcomes for the child were studied. Long-term respiratory morbidity was assessed using validated respiratory questionnaires at 6, 12 and 18 months of age and infant lung function test at around 12 months of age. Neurodevelopment was assessed using the Bayley Scales of Infant Development, second edition (BSID-II) at corrected age of 2 years.

RESULTS

Fifty-eight women were randomized to the study. Two babies were excluded from the analysis because of termination of pregnancy for lethal anomaly, leaving 56 participants (28 assigned to serial amnioinfusion and 28 to expectant management) recruited between 2002 and 2009. There was no significant difference in perinatal mortality (19/28 vs 19/28; relative risk (RR) 1.0 (95% CI, 0.70-1.43)) and maternal or neonatal morbidity. The overall chance of surviving without long-term respiratory or neurodevelopmental disability was 4/56 (7.1%); 4/28 (14.3%) in the amnioinfusion group and 0/28 in the expectant group (RR 9.0 (95% CI, 0.51-159.70)).

CONCLUSIONS

This pilot study found no major differences in maternal, perinatal or pregnancy outcomes. The study was not designed to show a difference between the groups and the number of survivors was too small to draw any conclusions about long-term outcomes. It does, however, signal that a larger definitive study to evaluate amnioinfusion for improvement in healthy survival is needed. The pilot suggests that, with appropriate funding, such a study is feasible.

Transabdominal amnioinfusion for improving fetal outcomes after oligohydramnios secondary to preterm prelabour rupture of membranes before 26 weeks

BACKGROUND

Preterm prelabour rupture of membranes (PPROM) before 26 weeks can delay lung development and can cause pulmonary hypoplasia, as a result of oligohydramnios. Restoring the amniotic fluid volume by transabdominal amnioinfusion might prevent abnormal lung development and might have a protective effect for neurological complications, fetal deformities and neonatal sepsis.

OBJECTIVES

To assess the effectiveness of transabdominal amnioinfusion in improving perinatal outcome in women with oligohydramnios secondary to rupture of fetal membranes before 26 weeks.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 April 2013).

SELECTION CRITERIA

All randomised controlled trials comparing transabdominal amnioinfusion with no transabdominal amnioinfusion. Cluster- or quasi-randomised trials were not eligible for inclusion. In cases where only an abstract was available, we attempted to find the full articles.

DATA COLLECTION AND ANALYSIS

Two review authors assessed trials for inclusion. No eligible trials were identified.

MAIN RESULTS

There are no included studies.

AUTHORS' CONCLUSIONS

There is currently no evidence to evaluate the use of transabdominal amnioinfusion in women with oligohydramnios secondary to rupture of fetal membranes before 26 weeks for improving perinatal outcome. Further research examining the effects of this intervention is needed. Two randomised controlled trials are ongoing but final data have not yet been published.

Predictive factors for neonatal survival in women with periviable preterm rupture of the membranes

OBJECTIVE

To identify clinical, hematological or instrumental factors available at the time of the diagnosis that may predict neonatal survival in periviable preterm premature rupture of the membranes (PROM).

METHODS

We report on a cohort (n = 85) of women with periviable PROM (14-23.6 weeks' gestation) occurring over a 10-year period in a single institution. The main outcome chosen was the survival rate beyond the neonatal period. Variables considered were those available at 24 h after admission.

RESULTS

The overall survival rate was 49%. In the multivariate analysis, significant contributions for the prediction of neonatal survival were provided by four variables: genetic amniocentesis-related cause of PROM (p < 0.001), gestational age at PROM (p = 0.019), CRP > 1 mg/dl within 24 h after admission (p = 0.042) and oligohydramnios (largest vertical pocket ≤2 cm) (p = 0.041). The corresponding adjusted odds ratio (OR)s were 73.9 (95% CI: 7.9-694.7), 1.5 (95% CI: 1.1-2.0) per week, 0.26 (95% CI: 0.07-0.95) and 0.20 (95% CI: 0.04-0.93), respectively.

CONCLUSIONS

Genetic amniocentesis-related cause of PROM, gestational age at PROM, C-reactive protein >1 mg/dl and oligohydramnios are significantly associated with survival in women with periviable PROM. The evaluation of these few and easily available variables may help physicians and patients in the decision-making process of this demanding condition.

[Rupture of membranes: pathophysiology, diagnosis, consequences and management]

Rupture of membranes (ROM) depends on mechanical stretch, extracellular matrix components imbalance and increased apoptosis. It occurs in 2 to 3% of all pregnancies before 37 weeks' gestation (WG) and in up to 10% at term. Main consequences are labor induction and risk of maternal-fetal infection. ROM is associated with one third of preterm births and about 20% of perinatal mortality. This review deals with recent knowledge concerning ROM including diagnosis and management. In many cases, ROM is easily identified by clinical examination. In other cases, the use of vaginal pH appears to be less efficient than the use of immunochromatographic strips based on IGFBP-1 or PAMG-1 detection. Before 34WG, conservative management consists in in utero transfer, antibioprophylaxis and corticosteroids. After 37WG, delivery is the most appropriate option. Between 34 and 37WG, recent studies demonstrate that induction of labour does not improve pregnancy outcomes. Therefore, expectant management can be the first option between 34 and 37WG when no active infection is suspected especially in case of unfavourable cervix.

Premature rupture of membranes before 28 weeks managed expectantly: maternal and perinatal outcomes in a developing country

This study aimed to assess outcomes of expectant management for early preterm premature rupture of membranes (PPROM). This retrospective cohort involved 66 women with PPROM <28 weeks managed in a single hospital (1999-2006). Main outcomes were chorioamnionitis, severe maternal morbidity (maternal sepsis, haemorrhage/blood transfusion, hysterectomy or admission to intensive care unit), maternal mortality, low birth weight, preterm birth, neonatal infection and perinatal mortality. Mean gestational ages at PPROM and delivery were 21.7 ± 4.2 and 28.4 ± 5.9 weeks, respectively. Chorioamnionitis was diagnosed in 47%; no cases of severe maternal morbidity or mortality occurred. Stillbirth rate was 25.7% and >80% of infants were delivered before 34 weeks. Neonatal infection was diagnosed in 42.9% of the 49 live-births. Overall survival rate was 57.6%. Expectant management of PPROM <28 weeks resulted in high rates of chorioamnionitis and preterm deliveries but in over half of the cases, a live infant was discharged home.

[Management and outcomes of pregnancies complicated by preterm premature rupture of membranes before 26 weeks of gestation]

OBJECTIVE

To evaluate short-term outcomes of pregnancies complicated by preterm premature rupture of membranes (PPROM) before 26 weeks of gestation (wg).

PATIENTS AND METHODS

Forty patients were included in a retrospective study from 1998 to 2008.

RESULTS

Fifty percent of PPROM occurred before 23 wg. Survival rate was 21.4% when PPROM occurred before 22 wg versus 54.5% when it occurred between 22 and 23+6 wg and reached 80% after 24 wg (P=0.006). Perinatal mortality affected more frequently primigravida women (OR=5.16; IC9 5% [0.99-36.59]). Invasive procedures before PPROM did not affect survival rates. Smoking induced shorter latency (19.1±13.8 vs. 40.3±2.3j; P=0.01). Chorioamnionitis complicated all pregnancies terminated before 26 wg versus 50% of pregnancies terminated after 26 wg (P=0.02). In case of chorioamnionitis, 70% of the germs were identified prenatally. Patients whose CRP was higher than 6 mg/L at the time of PPROM had a higher fetal mortality rate (63.6% vs. 27.8%; P=0.02; OR=4.3; IC95% [0,99-22,1]). No significant difference was found in the occurrence of chorioamnionitis based on gestational age at PPROM, result of the vaginal swab on admission or the amount of amniotic fluid.

DISCUSSION AND CONCLUSION

The gestational age of PPROM and the one of delivery are the major prognostic factors. Primigravida women are more exposed to perinatal mortality. CRP appears to be a predictive factor of perinatal mortality.

Rupture of membranes before the age of viability and birth after the age of viability: comparison of outcomes in a matched cohort study

OBJECTIVE

To compare composite adverse outcome rate of infants <32 weeks gestational age (GA) who were born after preterm premature rupture of membranes (PPROM) at previable gestation to those born without PPROM.

STUDY DESIGN

Retrospective review of prospective collected data for infants discharged between 2004 and 2007 was conducted. Cases were infants with >7 days of PPROM that occurred before 24 weeks. Matched cohort consisted of infants born without PPROM (matched for GA, sex and admission date). Composite adverse outcome was assessed considering death or any of the following three severe morbidities (severe neurological injury, severe retinopathy of prematurity or chronic lung disease).

RESULT

The 29 cases had higher mean severity of illness score compared with 74 matched infants. Mean duration of ROM was 45 vs 2 days and mean GA at the ROM was 21 vs 27 weeks, respectively. Logistic regression confirmed significantly higher risk of composite adverse outcome rates for cases (69 vs 47%; P=0.02, adjusted odds ratio 4.0, 95% CI 1.2, 13.6).

CONCLUSION

The survival rate for infants born at <32 weeks following PPROM at previable age has improved significantly; however, these infants had a higher rate of adverse composite neonatal outcome.

Transabdominal amnioinfusion in preterm premature rupture of membranes

OBJECTIVE

To evaluate the effect of transabdominal amnioinfusion on prolongation of pregnancy, and maternal and neonatal outcomes in preterm premature rupture of membranes (pPROM).

METHODS

We conducted a prospective randomized controlled study of women with pPROM during singleton live pregnancy-between 26 and 33+6weeks-whose amniotic fluid index (AFI) was less than the 5th percentile. The study group underwent transabdominal amnioinfusion at admission and then weekly if their AFI fell below the 5th percentile again. The control group received expectant management.

RESULTS

The difference in the mean interval from pPROM to delivery between the groups was not statistically significant. Neonatal and maternal outcomes were significantly improved in the study group compared with the control group (fetal distress [10% vs 37%]; early neonatal sepsis [17% vs 63%]; neonatal mortality [17% vs 63%]; spontaneous delivery [83% vs 53%]; and postpartum sepsis [7% vs 33%]).

CONCLUSION

Transabdominal amnioinfusion reduced fetal distress, early neonatal sepsis, and neonatal mortality. In the study group, more participants delivered spontaneously and there were fewer cases of postpartum sepsis, although the pPROM-delivery interval was not increased.

The management of preterm premature rupture of the membranes near the limit of fetal viability

Preterm premature rupture of the membranes near the limit of fetal viability is an uncommon complication of pregnancy, affecting approximately 4 in 1000 gravidas. However, maternal, fetal, and neonatal complications resulting from this condition are significant and include chorioamnionitis, pulmonary hypoplasia, restriction deformities, fetal loss, and complications of extreme prematurity among surviving infants. In this article, we review the literature regarding pregnancy outcomes after preterm premature rupture of the membranes near the limit of viability, and the data on traditional and nontraditional interventions to improve outcomes. An approach to patients who present with preterm premature rupture of the membranes near the limit of viability will be proposed.

[Premature rupture of membranes before 32 weeks of gestation: prenatal prognosis factors]

OBJECTIVE

Premature preterm rupture of membranes (PPROM) accounts for a significant part of overall perinatal mortality and morbidity. This study aims to define potential prognostic factors for neonatal outcome.

PATIENTS AND METHODS

One hundred and thirty-one pregnancies complicated with PPROM at between 26 and 32 weeks were retrospectively reviewed over a three-year period. The influence of chorioamnionitis on perinatal morbidity and mortality was assessed using a composite outcome.

RESULTS

On admission, gestational age (GA) at diagnosis, fetal heart rate anomalies and increasing severity of clinical features of chorioamnionitis were significantly related with an adverse outcome. Significant factors associated with a favourable outcome were an administration of steroids for lung maturation, prophylactic antibiotics and tocolytic therapies. Stratifying according to GA at PPROM, the survival rates were 43 and 52% at before 22 weeks and between 22 and 26 weeks respectively. The prognosis dramatically improved after 26 weeks with an 84.6% rate of survival without impairment. Although this rate reached 97.5% after 30 weeks, there was no statistical evidence supporting any benefit to prolong pregnancies beyond this point. The complete expression of chorioamnionitis independently increased the mortality rate by 41% (OR=1.41; 95% CI [0.99-2.01]. Overall, the most relevant factor was GA at delivery, levelling the prognostic value of GA at diagnosis.

DISCUSSION AND CONCLUSION

If no consensus rules PPROM at the moment, the most efficient prognosis factor before 34 weeks is mostly determined by GA at delivery.

Amnioinfusion in preterm PROM: effects on amnion and cord histology

OBJECTIVE

To investigate the effects of transabdominal amnioinfusion (TA) on the histology of amnion (A) and umbilical cord (UC).

STUDY DESIGN

From a cohort of 56 singleton pregnancies with premature rupture of membranes (PROM) at <or=24.6 weeks, we excluded those who did not develop severe oligohydramnios (n=12). Of the 44 patients, 29 consented to TA and 15 declined the procedure. TA was performed with normal saline solution.

RESULT

Women who consented to TA underwent a median of three procedures had a gestational age at PROM of 18.7 weeks and at delivery of 26.1 weeks, with a latency of 50 days. Compared with subjects who declined the procedure, TA had a beneficial effect on clinical variables, mediated primarily by a longer latency. TA was not associated with identifiable effects on the histologic features of A or UC.

CONCLUSION

A and UC histology is not significantly affected by exposure to saline solution even for prolonged periods of time.

Acute and chronic respiratory diseases in pregnancy: associations with spontaneous premature rupture of membranes

OBJECTIVE

To examine whether acute and chronic respiratory diseases are associated with an increased risk of spontaneous premature rupture of the membranes (PROM).

METHODS

We used the 1993-2004 National Hospital Discharge Survey data of singleton deliveries in the USA (N = 41 250 539). The International Classification of Diseases Ninth Revision was utilized to identify acute (acute upper respiratory diseases, viral/bacterial pneumonia, and acute bronchitis/bronchiolitis) and chronic (chronic bronchitis and asthma) respiratory conditions and spontaneous PROM. All analyses were adjusted for potential confounders.

RESULTS

The incidence of PROM was 5%, and rates of acute and chronic respiratory conditions were 2.1 and 9.5 per 1000 pregnancies, respectively. Chronic bronchitis was associated with a reduced risk of PROM (RR 0.39, 95% CI 0.31, 0.48). Asthma was significantly associated with PROM at preterm (RR 1.15, 95% CI 1.14, 1.17) and term (RR 1.27, 95% CI 1.23, 1.30). Stratification by race showed that acute upper respiratory disease was associated with preterm PROM in whites (RR 1.90, 95% CI 1.71, 2.11) and blacks (RR 6.76, 95% CI 5.67, 8.07). Viral/bacterial pneumonia was associated with preterm PROM in blacks and term PROM in both races. Asthma was associated with term PROM in blacks but not whites.

CONCLUSIONS

Acute respiratory diseases and asthma during pregnancy are associated with spontaneous PROM, with substantially stronger association among blacks than whites. We speculate that timely diagnosis and treatment, coupled with closely mentoring of pregnant women may help reduce the rate of PROM and associated complications.

Management of premature rupture of membranes before 25 weeks

OBJECTIVES

The aim of our study was to define the benefits and risks related to expectant management in the midtrimester rupture of membranes and to assess the prognostic factors in order to give objective informations to parents facing these obstetrical situations.

STUDY DESIGN

We conducted a retrospective study. The study population included 49 patients with premature rupture of membranes at 16-23 weeks' gestation during the period January 1998-June 2003. The main criterion for judgement was neonate survival. Statistical analysis included chi2-test for the qualitative variables and Student's test for the quantitative variables. The threshold for significance was 5%.

RESULTS

Twenty couples out of 49 chose medical termination of pregnancy. Among the 29 other pregnancies, the mean latency period was 2.1 weeks. The mean gestational age at delivery was 23.2 weeks. Nineteen patients were delivered after 22 weeks. The main prognostic factors were the initial amniotic fluid index (2.9 cm versus 0.8 cm) (p=0.042) and gestational age at delivery (26.7 weeks versus 22.6 weeks) (p<0.001). About 2% of the pregnancies were complicated by maternal infection. Eighty-three percent of the survivors had neonatal respiratory distress syndrome. 41.2% of them presented sepsis. We observed no cases of severe intraventricular haemorrhage. The number of infants born after 24 weeks of gestation and still alive at 1 week was 12, representing 24% of pregnancies and 63% of the infants born after 24 weeks.

CONCLUSION

Expectant management can be widely suggested to patients. However, termination of pregnancy is acceptable, in cases with a poor prognosis including anamnios and premature rupture of membranes before 21 weeks.

Successful outcome following pre-viability amniorrhexis

A 34-years-old primigravida conceived following a fourth attempt at in vitro fertilization and embryo transfer for severe bilateral tubal disease and grade IV endometriosis. Pregnancy progressed well until 17 weeks gestation when she spontaneously ruptured her membranes. She elected to continue with the pregnancy despite the significant risks associated with prolonged rupture of membranes (PROM) and anhydramnion at extremes of viability. Pregnancy was carried to 28 weeks gestation, when delivery was necessitated by a major antepartum haemorrhage following abruption placentae. A male infant weighing 1,100 g was delivered by emergency caesarean section in good condition, and with no features oligohydramnion tetrad (Potter's features, skeletal deformities, intrauterine growth restriction, and pulmonary hypoplasia). This case adds to the small number of cases in the literature of successful outcome following prolonged pre-viability PROM. Counselling and psychological support to the parents in this situation is extremely important since the anxiety and uncertainty associated with expectant management of PROM does not end with the "successful" delivery of the baby but persists all through the neonatal period and for several years later.

Manufacture of a Cell-free Amnion Matrix Scaffold that Supports Amnion Cell Outgrowth In Vitro

We manufactured a cell-free extracellular matrix scaffolds in order to obtain a support material for amnion cell outgrowth, eventually being used for repair of prematurely ruptured fetal membrane. Human preterm or term amnion tissue was separated into its collagenous extracellular matrix and cell components. The acellular scaffold was explored for its capacity to support regrowth of isolated human amnion epithelial or mesenchymal cells in vitro. The outgrowth of amnion cells on and in the scaffold was investigated by scanning and transmission electron microscopy, and confocal laser scanning microscopy. Cell-free amnion matrix scaffolds demonstrated a porous collagen fiber network similar as in native amnion. Inoculation of acellular amnion scaffolds with human amnion cells revealed that its property to support amnion cell outgrowth was retained. Amnion epithelial and mesenchymal cells were found to grow into dense layers on the surface of the scaffold within 3-4 days and 7-8 days, respectively, and to some extent, invaded the scaffold during the culture period. Manufactured acellular amnion matrix retains structural and functional properties required for cell outgrowth in vitro. It may become useful to repair prematurely ruptured fetal membranes.

Premature rupture of membranes at 20 weeks: report of a successful outcome after transcervical application of fibrin glue

A 30-year-old primigravida was admitted to hospital at 20 weeks of gestation because of premature rupture of membranes and oligohydramnios. The patient was maintained in bed rest and given intravenous ampicillin. Forty-eight hours later, after documenting the absence of infection and maintenance of the oligohydramnios, fibrin glue was applied transcervically under ultrasound control. There was subjective improvement in amniotic fluid volume after treatment, but always within the criteria of oligohydramnios. Fibrin glue application was repeated twice due to reported increase in fluid loss and diminished amniotic fluid volume on ultrasound. Amoxicillin per os was started at 23 weeks, and clavulanic acid was added at 26 weeks due to the isolation of an Escherichia coli on cervical-vaginal cultures. No signs of infection ensued until 34 weeks, when an axillary temperature of 39.5 degrees C was detected together with a non-reassuring cardiotocographic pattern, the latter leading to the performance of an urgent cesarean section. The newborn had an Apgar score of 9/10/10, umbilical artery pH of 7.32, and no external deformities. He showed no signs of lung hypoplasia and required no oxygen supplementation. Oropharyngeal and blood cultures revealed an E. coli infection and antibiotic treatment was started. No further complications occurred and he was discharged home on the 8th day of life. At 12 months, the child reveals a normal development. The mother had a mild and short-lasting wound infection and was discharged on the 8th postoperative day.

Predictors of perinatal survival in a cohort of pregnancies with severe oligohydramnios due to premature rupture of membranes at <26 weeks managed with serial amnioinfusions

OBJECTIVE

To evaluate whether successful amnioinfusion is an independent predictor of perinatal survival in a cohort of cases with extreme and persistent oligohydramnios due to preterm premature rupture of membranes (pPROM) who reached viability and were managed with serial amnioinfusions.

STUDY DESIGN

We included all consecutive singleton pregnancies with pPROM at <26 weeks and oligohydramnios lasting >4 days between 1/1991 and 12/2001 and who consented to undergo amnioinfusion (n=77). Women received serial transabdominal amnioinfusions in an attempt to maintain a pocket of fluid >2 cm. The procedure was deemed successful if the median deepest pocket of fluid during the latency period was >2 cm. Excluded were miscarriages (n=10), fetal deaths before viability (24 weeks) (n=15), and cases that did not develop oligohydramnios (n=17). Prenatal predictors of outcome were compared between cases who survived the perinatal period and those who did not using Wilcoxon rank-sum test, Fisher's exact test and stepwise logistic regression analysis, with a two-tailed P<0.05 considered significant.

RESULTS

Of the 35 patients fulfilling the study criteria, 20 (57%) survived the perinatal period. Perinatal survivors had similar gestational age at pPROM (P=0.68) and at first amnioinfusion (P=0.53) as those who died in the perinatal period, but longer latency (P=0.013). Consequently, median gestational age at delivery [29.2 (25.4-35.3) weeks versus 26.1 (24.0-34.0) weeks, P<0.001] and median birth weight [1220 (650-2240) g versus 863 (520-2200) g, P=0.001] were significantly greater among survivors than among those who died. Significant predictors of survival at univariate analysis were entered into a stepwise logistic regression analysis in the chronological order in which they normally occur. The analysis demonstrated that successful amnioinfusion (OR=6.9, 95% CI 1.2-40.4) and administration of steroids (OR=14.6, 95% CI 1.5-144.1) were independent and significant predictors of perinatal survival.

CONCLUSION

In a cohort of women with pPROM at <26 weeks and severe oligohydramnios managed with serial amnioinfusions, successful procedures and prenatal administration of corticosteroids are the only independent predictors of perinatal survival.

Risk factors for previable premature rupture of membranes or advanced cervical dilation: a case control study

OBJECTIVE

The purpose of this study was to identify risk factors for second trimester premature preterm rupture of membranes or advanced cervical dilation in a high-risk population.

STUDY DESIGN

A retrospective case control study was performed that compared women with premature preterm rupture of membranes or advanced cervical dilation to term control subjects. The cases included all singleton pregnancies between 14 and 24 weeks of gestation with premature preterm rupture of membranes or advanced cervical dilation between 1996 and 2000. The next 2 term deliveries were chosen as control subjects. The variables compared between cases and control subjects included pregnancy history, infectious and medical histories, cervical/uterine procedures, and habits. This study had institutional review board approval.

RESULTS

There were 102 women with premature preterm rupture of membranes, 56 women with advanced cervical dilation, and 316 control subjects. The mean gestational ages for premature preterm rupture of membranes or advanced cervical dilation were 20 +/- 2.6 and 19.9 +/- 2.6 weeks. Tobacco use, history of or current cervical incompetence, previous second trimester delivery, previous termination at <20 weeks of gestation, and previous premature preterm rupture of membranes were associated significantly with premature preterm rupture of membranes or advanced cervical dilation compared with term control subjects. When controlled for parity, age, marital status, and race, these variables remained significant. Bacterial vaginosis in current pregnancy was associated significantly with only advanced cervical dilation but not premature preterm rupture of membranes compared with control subjects. A history of Chlamydia was most common in the term control subjects (19.6%).

CONCLUSION

In a high-risk population of inner city women, only pregnancy history and tobacco use distinguished women with second trimester premature preterm rupture of membranes or advanced cervical dilation from term control subjects. No infectious risk factors distinguished control women from women with premature preterm rupture of membranes. The only modifiable risk identified was tobacco use.

Intracervical application of synthetic hydrogel sealant for preterm prelabor rupture of membranes: a case report

We report a case of prelabor rupture of membranes at 20 weeks' gestation where a hydrogel sealant was applied to the cervical canal in order to maintain an adequate liquor volume in the second trimester. The use of this agent for the purpose of creating plug has not been reported to date.

Preterm prelabour rupture of the membranes before 28 weeks: better than feared outcome of expectant management in Africa

OBJECTIVE

To document the prognosis after conservative management of patients with membrane rupture at gestations less than 28 weeks.

STUDY DESIGN

Prospective observational study of 78 women with confirmed membrane rupture at less than 28 weeks gestation, managed conservatively. Antibiotics were given from the time of membrane rupture till delivery. Patients were delivered if clinical infection supervened, there was fetal compromise, spontaneous labour ensued or if the pregnancy continued to 34 completed weeks gestation.

RESULTS

The mean gestational age at membrane rupture was 23.3+/-3.17 weeks (16.5-27.8) and the median 24 weeks. Mean latency period was 24.1+/-29.1 days (1.5-154) with a median of 12.5 days. Eight women (10%) delivered between 24 and 48 h, 25 (32%) within 7 days and 55 (70%) within 1 month. Of note is that 23 patients (30%) had latency periods of greater than 1 month. The mean gestational age at delivery was 26.7+/-3.92 weeks. Overall of the 78 women there were 81 fetuses delivered, of which 35 (43%) survived. Survival was related to latency period, birth weight and gestational age at delivery. Sixteen women (20%) developed chorioamnionitis. There was no increase in the incidence of clinical infection with increasing latency period. Compression limb abnormalities occurred in 17% of neonates and lung hypoplasia in 18%.

CONCLUSION

Conservative management of patients with very preterm prelabour membrane rupture offers a survival rate of at least 40% with no serious complications in a study of 78 women.

Sonographic myometrial thickness predicts the latency interval of women with preterm premature rupture of the membranes and oligohydramnios

OBJECTIVE

Term labor is associated with global thinning of the myometrium. We hypothesized that a thickened myometrium at the time of preterm premature rupture of membranes (PPROM) predicts less myometrial wall stress and, consequently, a longer latency interval.

STUDY DESIGN

Myometrial thickness was measured prospectively in 76 pregnant women enrolled in the following groups: PPROM (n=28, mean [range], gestational age [GA]: 29.5 weeks [w] [21.0 w-33.0 w]), preterm nonlabor control group (P-CTR), (n=21, GA: 27.5 w [23.0 w-32.0 w]) and term nonlabor control (T-CTR) (n=27, GA: 38.6 w [37.0 w-41.6 w]). All PPROM women had oligohydramnios (AFI: 1.4 cm [0.0 cm-5.1 cm]). MT was measured ultrasonographically at the midanterior, fundal, posterior, and lower uterine segment wall in cases and controls with an intraoperator variability <10%.

RESULTS

Women in the PPROM group displayed uniform thickness of the uterine body (mean +/- SEM, anterior: 10.6 +/- 0.6 mm, fundal: 10.7 +/- 0.7 mm, posterior: 8.9 +/- 0.5 mm, P=.078). At midanterior site the myometrium of the PPROM group was thicker compared to both P-CTR (P < .001) and T-CTR (P=.025) groups. This difference was preserved at the fundus (PPROM vs P-CTR, P < .001; PPROM vs T-CTR, P=.015). There was a positive correlation between fundal MT and latency period (r=0.43, P=0.02) that persisted after adjusting for GA (P=.04). A fundal MT less than 12.1 mm was 93.7% sensitive and 63.6% specific for the identification of women whose latency period was less than 120 hours.

CONCLUSION

Significant thickening of the anterior and fundal walls of the uterus follows PPROM. A thick myometrium in nonlaboring patients with PPROM is associated with longer latency interval. Sonographic evaluation of MT may represent an alternative clinical tool for the prediction of a short latency interval in women with PPROM.

Transabdominal amnioinfusion in preterm premature rupture of membranes: a randomised controlled trial

OBJECTIVE

To evaluate the role of transabdominal amnioinfusion in improving the perinatal outcomes of pregnancies complicated by preterm premature rupture of membranes (pPROM).

DESIGN

A randomised controlled trial.

SETTING

A teaching hospital in Italy, obstetric unit. Population Women with singleton pregnancies complicated by pPROM, between 24 + 0 and 32 + 6 weeks of gestation.

METHODS

Patients were randomised 24 hours after admission to our referral hospital, to expectant management with transabdominal amnioinfusion or expectant management only.

MAIN OUTCOME MEASURES

The effects of transabdominal amnioinfusion on pPROM-delivery interval and on perinatal outcomes.

RESULTS

Of the 65 women with pPROM 34 met the inclusion criteria. Seventeen women were assigned to amnioinfusion (the amnioinfusion group) and the other 17 to expectant management. Compared with the control group (median: 8 days; range: 3-14), the pPROM-delivery period was significantly longer in women who underwent amnioinfusion (median: 21 days; range: 15-29) (P < 0.05). Women with amnioinfusion were less likely to deliver within seven days since pPROM (RR: 0.18; range: 0.04-0.69 95% CI) or within two weeks (RR: 0.46; range: 0.21-1.02 95% CI). In the amnioinfusion group the neonatal survival was significantly higher at each gestational age (P < 0.01, Yates's correction for Log Rank Test) with a reduction in pulmonary hypoplasia.

CONCLUSIONS

We demonstrated that compared with standard expectant management the treatment with transabdominal amnioinfusion after pPROM resulted in significant prolongation of pregnancy and better neonatal outcomes.

Expectant management in spontaneous preterm premature rupture of membranes between 14 and 24 weeks' gestation

OBJECTIVE

To examine maternal and neonatal outcomes in expectant management of spontaneous preterm premature rupture of membranes (PPROM) before 24 weeks.

STUDY DESIGN

Patients presenting with spontaneous PPROM from 14 to 23 completed weeks' gestation between January 1, 1995 and December 31, 1999 were reviewed. A total of 108 pregnancies were evaluated; 57 patients elected expectant management.

RESULTS

Median latency from rupture of membranes (ROM) to delivery was 6 days; the overall survival rate was 26.3%. In ROM <20 weeks, a twin and a triplet pregnancy with loss of the presenting fetuses yielded the only survivors. In patients with ROM from 20 to 21 and 22 to 23 weeks, survival rates were 2/16 (12.5%) and 11/20 (55.0%), respectively. In all, 18/57 (31.6%) of patients developed chorioamnionitis. There was no maternal sepsis or death. There were three cases of pulmonary hypoplasia, all in patients with ROM <20 weeks.

CONCLUSIONS

Neonatal survival in spontaneous PPROM before 20 weeks is rare, irrespective of latency from ROM to delivery. When PPROM occurs from 20 to 24 weeks, survival improves with increasing gestational age at ROM and at delivery.

Preterm premature rupture of membranes, intrauterine infection, and oligohydramnios: risk factors for placental abruption

OBJECTIVE

To examine whether preterm premature rupture of membranes (PROM), intrauterine infection, and oligohydramnios are risk factors for placental abruption.

METHODS

Data for this retrospective cohort study were derived from the 1988 National Maternal and Infant Health Survey (N = 11,777). Association between abruption and these clinical risk factors was expressed as relative risk (RR) and 95% confidence interval (CI), with multivariate adjustment for potential confounders.

RESULTS

The overall incidence of abruption was 0.87%. The risk of abruption was 3.58-fold higher (95% CI 1.74-7.39) among women with preterm PROM (2.29%) compared with women with intact membranes (0.86%). The rates of abruption among women with and without intrauterine infection were 4.81% and 0.83%, respectively (RR 9.71, 95% CI 3.23-29.17). However, oligohydramnios was not associated with abruption (1.46% compared with 0.87%; RR 2.09, 95% CI 0.92-5.31). Compared with women with intact membranes, the RR for abruption among preterm PROM and whose membranes were ruptured for 24-47 hours and 48 hours or more before delivery, respectively, were 2.37 (95% CI 0.99-9.09), and 9.87 (95% CI 3.57-27.82). When preterm PROM was accompanied by intrauterine infections, the RR for abruption was 9.03 (95% CI 2.80-29.15) compared with women with intact membranes and no infections. Similarly, preterm PROM accompanied by oligohydramnios conferred over a 7.17-fold risk (95% CI 1.35-38.10) for abruption compared with women with neither of these 2 conditions.

CONCLUSION

Women presenting with preterm PROM are at increased risk of developing abruption, with the risk being higher either in the presence of intrauterine infections or oligohydramnios. Physicians managing patients with preterm PROM should be aware that these patients are at increased risk of developing abruption after 24 hours following preterm PROM.

Outcomes after expectant management of extremely preterm premature rupture of the membranes

OBJECTIVE

This study was undertaken to assess contemporary outcomes in pregnancies managed expectantly after extremely preterm premature (< or =24 weeks) premature rupture of the membranes (EPPROM).

STUDY DESIGN

We queried antepartum and ultrasound databases for patients with EPPROM. Data on pregnancy outcome and short-term neonatal outcomes were collected.

RESULTS

Forty-six patients with EPPROM were studied. Patients were hospitalized at 24 weeks' gestation and given antibiotics and antenatal steroids. Median gestational age at PPROM was 22.0 weeks (range 16.9-24 weeks); 43 (93%) elected expectant management, 2 of whom later had an intrauterine fetal death. Median latency period to delivery was 13 days (range 0-96 days), with mean gestational age at delivery of 25.8+/-3.4 weeks. Overall survival was 47% (27 of 57 infants), after a median hospital stay of 71 days (range 17-209 days). Ten (37%) of the survivors have serious sequelae.

CONCLUSION

Although significant pregnancy prolongation after previable PPROM occurs in many cases, neonatal outcomes remain poor.