Premature rupture of membrane at term: early induction versus expectant management

Use of vaginal dinoprostone for women with term prelabor rupture of membranes and an unfavorable cervix within 6 h versus within 6-24 h

BACKGROUND

Most guidelines propose inducing labor within 24 h following term (37 or more weeks of gestation) prelabor rupture of membranes (PROM). However, the exact timing for initiating induction within the 24 h period remains unknown. This study aims to comparatively assess the efficacy and safety of the use of vaginal dinoprostone within 6 h versus within 6-24 h for singleton pregnancies with PROM and an unfavorable cervix (Bishop score < 6).

METHODS

This was a retrospective cohort study including singleton pregnancies with PROM and an unfavorable cervix (Bishop score < 6) in which labor was induced using vaginal dinoprostone. Women were divided into two groups according to the timing of the use of induction (within 6 h versus within 6-24 h after PROM). Baseline maternal data, maternal and neonatal outcomes were recorded for statistical analysis.

RESULTS

450 women were included, 146 (32.4%) of whom were induced within 6 h of PROM and 304 (67.6%) were induced within 6-24 h. Cesarean delivery rate (15.8% versus 29.3%, p = 0.002) and nonreassuring fetal heart rate tracing (4.8% versus 10.5%, p = 0.043) in group with vaginal dinoprostone within 6 h were significantly lower than those in group with vaginal dinoprostone within 6-24 h. There was no significant differences in terms of duration from IOL to vaginal delivery.

CONCLUSION

Induction of labor within 6 h with vaginal dinoprostone after PROM for singleton pregnancies with an unfavorable cervix (Bishop score < 6) significantly associated with less cesarean section, less nonreassuring fetal heart rate tracing, compared to induction of labor within 6-24 h after PROM.

Chorioamnionitis after premature rupture of membranes in nulliparas undergoing labor induction: prostaglandin E2 vs. oxytocin

OBJECTIVES

To assess the risk of chorioamnionitis in nulliparous, term, singleton, vertex (NTSV) pregnancies with premature rupture of membranes (PROM) and an unfavorable cervix undergoing labor induction with either prostaglandin E2 (PGE2) or oxytocin only.

METHODS

Retrospective cohort of NTSV pregnancies presenting with PROM who underwent labor induction with either PGE2 (n=94) or oxytocin (n=181) between October 2015 and March 2019. The primary outcome of chorioamnionitis was compared between the two groups. Statistical analysis included Chi-squared and Wilcoxon rank-sum tests, as well as logistic regression. For time to delivery, a Cox proportional hazard regression was used to determine the hazard ratio (HR) and adjusted HR (aHR).

RESULTS

Baseline characteristics were similar between the two groups. Cervical ripening with PGE2 was associated with an increased rate of chorioamnionitis (18.1 vs. 6.1%; aOR 4.14, p=0.001), increased neonatal intensive care unit admissions (20.2 vs. 9.9%; aOR 2.4, p=0.02), longer time interval from PROM to delivery (24.4 vs. 17.9 h; aHR 0.56, p=<0.0001), and lower incidence of meconium (7.4 vs. 14.4%; aOR 0.26, p=0.01), compared to the oxytocin group.

CONCLUSIONS

Based on our data, the use of oxytocin appears both superior and safer compared to PGE2 in NTSV pregnancies with PROM undergoing labor induction.

Preterm and term prelabour rupture of membranes: A review of timing and methods of labour induction

Prelabour rupture of membranes (PROM) exposes both foetuses and mothers to the risk of infection. Induction of labour has been proposed to reduce this risk, but its neonatal and maternal risks and benefits must be balanced against those of expectant management (EM). Recent randomized studies of preterm PROM show that EM until 37 weeks of gestation is associated with lower overall neonatal morbidity. In term PROM, active management is associated with a shorter birth interval but not with lower rates of neonatal infection. Similar maternal and neonatal outcomes are reported regardless of whether induction uses oxytocin, PGE2, or oral misoprostol.

A systematic scoping review of clinical indications for induction of labour

BACKGROUND

The proportion of women undergoing induction of labour (IOL) has risen in recent decades, with significant variation within countries and between hospitals. The aim of this study was to review research supporting indications for IOL and determine which indications are supported by evidence and where knowledge gaps exist.

METHODS

A systematic scoping review of quantitative studies of common indications for IOL. For each indication, we included systematic reviews/meta-analyses, randomised controlled trials (RCTs), cohort studies and case control studies that compared maternal and neonatal outcomes for different modes or timing of birth. Studies were identified via the databases PubMed, Maternity and Infant Care, CINAHL, EMBASE, and ClinicalTrials.gov from between April 2008 and November 2019, and also from reference lists of included studies. We identified 2554 abstracts and reviewed 300 full text articles. The quality of included studies was assessed using the RoB 2.0, the ROBINS-I and the ROBIN tool.

RESULTS

68 studies were included which related to post-term pregnancy (15), hypertension/pre-eclampsia (15), diabetes (9), prelabour rupture of membranes (5), twin pregnancy (5), suspected fetal compromise (4), maternal elevated body mass index (BMI) (4), intrahepatic cholestasis of pregnancy (3), suspected macrosomia (3), fetal gastroschisis (2), maternal age (2), and maternal cardiac disease (1). Available evidence supports IOL for women with post-term pregnancy, although the evidence is weak regarding the timing (41 versus 42 weeks), and for women with hypertension/preeclampsia in terms of improved maternal outcomes. For women with preterm premature rupture of membranes (24-37 weeks), high-quality evidence supports expectant management rather than IOL/early birth. Evidence is weakly supportive for IOL in women with term rupture of membranes. For all other indications, there were conflicting findings and/or insufficient power to provide definitive evidence.

CONCLUSIONS

While for some indications, IOL is clearly recommended, a number of common indications for IOL do not have strong supporting evidence. Overall, few RCTs have evaluated the various indications for IOL. For conditions where clinical equipoise regarding timing of birth may still exist, such as suspected macrosomia and elevated BMI, researchers and funding agencies should prioritise studies of sufficient power that can provide quality evidence to guide care in these situations.

Neonatal complications in women with premature rupture of membranes (PROM) at term and near term and its correlation with time lapsed since PROM to delivery

Premature rupture of membranes (PROM) is a common problem with controversies in its management. The aim of our study was to find out the prevalence of neonatal complications and their correlation with the latent period in babies born to mothers with PROM at 34-40 weeks of gestation. This prospective cohort study was performed on 200 pregnant women with PROM at or near term. After birth, neonates were screened for sepsis. Other outcome measures included birth asphyxia, stay in the Neonatal Intensive Care Unit (NICU) and neonatal mortality. These were correlated against time spent from PROM. Duration after which risk of neonatal sepsis increased immensely was calculated by ROC. The prevalence of specific neonatal complications was as follows: birth asphyxia (8%); neonatal sepsis (4%); NICU admission (26%); and neonatal mortality (2%). Complications increased with an increasing latent period. Beyond 37 h of latency, the rate of neonatal sepsis increases dramatically. In conclusion, pregnancies with PROM at and near term should not be managed expectantly. All neonates born after 37 h of latent PROM should be stringently evaluated for sepsis.

[Term Prelabor Rupture of Membranes: CNGOF Guidelines for Clinical Practice - Timing of Labor Induction]

OBJECTIVE

To assess the effect of immediate induction versus expectant management on maternal and neonatal outcomes in case of term prelabor rupture of membranes.

METHODS

We searched Medline Database, Cochrane Library and consulted international guidelines.

RESULTS

In case of term prelabor rupture of membranes, induction of labor is associated with shorter rupture of membranes to delivery intervals when compared to expectant management, if induction is conducted with oxytocin (LE2), prostaglandin E2 (LE2) or misoprostol (LE2), but not when induction is conducted with Foley® catheter (LE2), osmotic dilatator (LE2) or acupuncture (LE2). The strongest evidence to date comes from a large international randomized study, the TERMPROM study, which included over 5000 women between 1992 and 1995. This study compared immediate induction with oxytocin or prostaglandin E2 to expectant management up to 96hours, followed by induction by oxytocin or prostaglandin E2. Immediate induction was not associated with a decreased neonatal infection rate (LE1), even among women with a positive streptococcus B vaginal swab (LE2). Thus, expectant management can be offered without increasing the neonatal infection risk (Grade B). Induction with oxytocin was associated with a decreased risk of intra-uterine infection and postpartum fever in the TERMPROM study (LE2), however, this study had significant limitations concerning this outcome (unknown streptococcus B status and low rate of prophylactic antibiotics), and this association was not found in other smaller studies. This decrease was not observed with induction by prostaglandin E2. In the TERMPROM study, induction was not associated with an increase or decrease in the rate of cesarean section (LE2), whatever the parity (LE2) or Bishop score at admission (LE3). Induction can thus be proposed without increasing the cesarean section risk (Grade B). There is no study evaluating expectant management over 4 days.

CONCLUSION

In case of term prelabor rupture of membranes, induction can be offered without increasing the cesarean section risk (Grade B). Expectant management can be offered without increasing the neonatal infection risk (Grade B), even among women with a positive streptococcus B vaginal swab (Professional consensus). The optimal moment of induction will therefore be guided by the maternity wards organization and women's preference after having informed them of the risks and benefits associated with induction and expectant management (Professional consensus). In case of meconial fluid or term prelabor rupture of membranes>4 days, induction must be offered (Professional consensus).

Planned early birth versus expectant management (waiting) for prelabour rupture of membranes at term (37 weeks or more)

BACKGROUND

Prelabour rupture of membranes (PROM) at term is managed expectantly or by planned early birth. It is not clear if waiting for birth to occur spontaneously is better than intervening, e.g. by inducing labour.

OBJECTIVES

The objective of this review is to assess the effects of planned early birth (immediate intervention or intervention within 24 hours) when compared with expectant management (no planned intervention within 24 hours) for women with term PROM on maternal, fetal and neonatal outcomes.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register (9 September 2016) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials of planned early birth compared with expectant management (either in hospital or at home) in women with PROM at 37 weeks' gestation or later.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion, extracted the data, and assessed risk of bias of the included studies. Data were checked for accuracy.

MAIN RESULTS

Twenty-three trials involving 8615 women and their babies were included in the update of this review. Ten trials assessed intravenous oxytocin; 12 trials assessed prostaglandins (six trials in the form of vaginal prostaglandin E2 and six as oral, sublingual or vaginal misoprostol); and one trial each assessed Caulophyllum and acupuncture. Overall, three trials were judged to be at low risk of bias, while the other 20 were at unclear or high risk of bias.Primary outcomes: women who had planned early birth were at a reduced risk of maternal infectious morbidity (chorioamnionitis and/or endometritis) than women who had expectant management following term prelabour rupture of membranes (average risk ratio (RR) 0.49; 95% confidence interval (CI) 0.33 to 0.72; eight trials, 6864 women; Tau² = 0.19; I² = 72%; low-quality evidence), and their neonates were less likely to have definite or probable early-onset neonatal sepsis (RR 0.73; 95% CI 0.58 to 0.92; 16 trials, 7314 infants;low-quality evidence). No clear differences between the planned early birth and expectant management groups were seen for the risk of caesarean section (average RR 0.84; 95% CI 0.69 to 1.04; 23 trials, 8576 women; Tau² = 0.10; I² = 55%; low-quality evidence); serious maternal morbidity or mortality (no events; three trials; 425 women; very low-quality evidence); definite early-onset neonatal sepsis (RR 0.57; 95% CI 0.24 to 1.33; six trials, 1303 infants; very low-quality evidence); or perinatal mortality (RR 0.47; 95% CI 0.13 to 1.66; eight trials, 6392 infants; moderate-quality evidence).

SECONDARY OUTCOMES

women who had a planned early birth were at a reduced risk of chorioamnionitis (average RR 0.55; 95% CI 0.37 to 0.82; eight trials, 6874 women; Tau² = 0.19; I² = 73%), and postpartum septicaemia (RR 0.26; 95% CI 0.07 to 0.96; three trials, 263 women), and their neonates were less likely to receive antibiotics (average RR 0.61; 95% CI 0.44 to 0.84; 10 trials, 6427 infants; Tau² = 0.06; I² = 32%). Women in the planned early birth group were more likely to have their labour induced (average RR 3.41; 95% CI 2.87 to 4.06; 12 trials, 6945 women; Tau² = 0.05; I² = 71%), had a shorter time from rupture of membranes to birth (mean difference (MD) -10.10 hours; 95% CI -12.15 to -8.06; nine trials, 1484 women; Tau² = 5.81; I² = 60%), and their neonates had lower birthweights (MD -79.25 g; 95% CI -124.96 to -33.55; five trials, 1043 infants). Women who had a planned early birth had a shorter length of hospitalisation (MD -0.79 days; 95% CI -1.20 to -0.38; two trials, 748 women; Tau² = 0.05; I² = 59%), and their neonates were less likely to be admitted to the neonatal special or intensive care unit (RR 0.75; 95% CI 0.66 to 0.85; eight trials, 6179 infants), and had a shorter duration of hospital (-11.00 hours; 95% CI -21.96 to -0.04; one trial, 182 infants) or special or intensive care unit stay (RR 0.72; 95% CI 0.61 to 0.85; four trials, 5691 infants). Women in the planned early birth group had more positive experiences compared with women in the expectant management group.No clear differences between groups were observed for endometritis; postpartum pyrexia; postpartum antibiotic usage; caesarean for fetal distress; operative vaginal birth; uterine rupture; epidural analgesia; postpartum haemorrhage; adverse effects; cord prolapse; stillbirth; neonatal mortality; pneumonia; Apgar score less than seven at five minutes; use of mechanical ventilation; or abnormality on cerebral ultrasound (no events).None of the trials reported on breastfeeding; postnatal depression; gestational age at birth; meningitis; respiratory distress syndrome; necrotising enterocolitis; neonatal encephalopathy; or disability at childhood follow-up.In subgroup analyses, there were no clear patterns of differential effects for method of induction, parity, use of maternal antibiotic prophylaxis, or digital vaginal examination. Results of the sensitivity analyses based on trial quality were consistent with those of the main analysis, except for definite or probable early-onset neonatal sepsis where no clear difference was observed.

AUTHORS' CONCLUSIONS

There is low quality evidence to suggest that planned early birth (with induction methods such as oxytocin or prostaglandins) reduces the risk of maternal infectious morbidity compared with expectant management for PROM at 37 weeks' gestation or later, without an apparent increased risk of caesarean section. Evidence was mainly downgraded due to the majority of studies contributing data having some serious design limitations, and for most outcomes estimates were imprecise.Although the 23 included trials in this review involved a large number of women and babies, the quality of the trials and evidence was not high overall, and there was limited reporting for a number of important outcomes. Thus further evidence assessing the benefits or harms of planned early birth compared with expectant management, considering maternal, fetal, neonatal and longer-term childhood outcomes, and the use of health services, would be valuable. Any future trials should be adequately designed and powered to evaluate the effects on short- and long-term outcomes. Standardisation of outcomes and their definitions, including for the assessment of maternal and neonatal infection, would be beneficial.