Management of prelabour rupture of the membranes in term primigravidae: report of a randomized prospective trial

Maternal and perinatal infectious morbidity in term prelabor rupture of membrane according to two induction of labor protocols

PURPOSE

The optimal labor-induction protocol in women with prelabor rupture of membranes (PROM) is unknown. Whether the management of women with a previous cesarean delivery (CD) with PROM is different remains controversial. We investigated maternal and perinatal outcomes according to two induction protocols of 24 h vs. 12 h.

METHODS

In July 2021, our protocol of induction of labor in term-PROM was extended from 12 h to 24 h post-PROM. We compared obstetrical and neonatal outcomes before and after the change. A subgroup analysis of women with previous CD was performed. Results were compared using a univariate analysis. A multivariable model was described to predict neonatal intensive care unit admission (NICU) and clinical chorioamnionitis.

RESULTS

The 24 h and 12 h ROM-to-induction protocol groups included 962 and 802 women, respectively. In the 24 h group, a higher proportion of women labored spontaneously (p < 0.001), the rate of chorioamnionitis was higher (p = 0.017), and the CD rate was similar. Admission to the NICU (p = 0.012), antibiotic administration (p = 0.003), and respiratory distress (p = 0.002) were also greater in the 24 h induction group. Among women with a history of CD (n = 143), the need for oxytocin (p = 0.003) and delivery by CD (p = 0.016) were lower in the 24 vs. 12 h group.

CONCLUSION

Our results advocate shared decision-making in the expectant management of term-PROM. Women should be informed of the lower chance for induction and the higher risk of infections and neonatal complications with a 24-h induction approach. Longer expectant management in women with a previous CD resulted in significantly lower induction and CD rates.

Pre-labour Rupture of Membranes at Term in Women With Gestational Diabetes and the Risk of Neonatal Hypoglycemia

OBJECTIVES

The management for improving maternal and neonatal outcomes of women with gestational diabetes mellitus (GDM) arriving at the delivery ward with pre-labour rupture of membranes (PROM) has not been elucidated. We tested the hypothesis that prolonged PROM in women with GDM would result in higher rates of neonatal hypoglycemia.

METHODS

We retrospectively enrolled women with diet or insulin-controlled GDM who presented with spontaneous clear PROM. Each woman was allocated into one of two groups based on the PROM-delivery time: <18 hours (group 1) and ≥18 hours (group 2). The primary outcome was the incidence of neonatal hypoglycemia, defined as glucose <40 mg/dL (2.2 mmol/L) within 24 hours of birth.

RESULTS

We ultimately analyzed 631 cases of GDM (6.7%), 371 with PROM-delivery <18 hours, and 260 with PROM-delivery ≥18 hours. The incidence of neonatal hypoglycemia did not differ between the two groups, reaching 7.3%. Women in group 2 were at increased risk of both cesarean delivery (20% vs. 12.4%, P < 0.01) and maternal chorioamnionitis morbidity (6.5% vs. 1.3%, P < 0.001).

CONCLUSIONS

In a sub-group of women with GDM, a PROM-delivery time ≥18 hours is not associated with higher rates of neonatal hypoglycemia, but higher rates of chorioamnionitis and cesarean delivery were noted. Therefore, we suggest consideration for early delivery when managing women with GDM and PROM.

Systematic review on the management of term prelabour rupture of membranes

INTRODUCTION

Prelabour rupture of membranes at term affects approximately 10% of women during pregnancy, and it is often associated with a higher risk of infection than when the membranes are intact. In an attempt to control the risk of infection, two main approaches have been used most widely in clinical practice: induction of labour (IOL) soon after the rupture of membranes, also called active management (AM), and watchful waiting for the spontaneous onset of labour, also called expectant management (EM). In addition, previous studies have demonstrated that vaginal examinations increase the risk of chorioamnionitis. However, the effect of vaginal examinations in the context of prelabour rupture of membranes have not been researched to the same extent.

METHODS

This systematic review analyses and critiques the latest research on the management of term prelabour rupture of membranes, including the effect of vaginal examinations during labour, with a focus on the outcomes of both normal birth, and chorioamnionitis. Due to its complexity, three research questions were identified using the PICO diagram, and subsequently, the results from these searches were combined. The systematic review aimed to identify randomised controlled trials (RCTs) and observational studies that compared active vs expectant management, included number of vaginal examinations and had chorioamnionitis and/or normal birth as outcomes. The following databases were used: MEDLINE, EMBASE, Maternity and Infant care, LILACS, CINAHL and the Cochrane Central Register of Controlled trials. Quality was assessed using a tool developed especifically for this study that included questions from CASP and the Cochrane risk of bias tool. Due to the high degree of heterogeneity meta-analysis was not deemed appropriate. Therefore, simple narrative analysis was carried out.

RESULTS

Thirty-two studies met the inclusion criteria, of which 27 were RCTs and 5 observational studies. The overall quality of the studies wasn't high, 15 out of the 32 studies were deemed to be low quality and only 17 out of 32 studies were deemed to be of intermediate quality. The systematic review revealed that the management of term prelabour rupture of membranes continues to be controversial. Previous research has compared active management (Induction of labour shortly after the rupture of membrane) against expectant management (watchful waiting for the spontaneous onset of labour). Although previous studies have demonstrated that vaginal examinations increase the risk of chorioamnionitis, no prospective studies have included an intervention to reduce the number of vaginal examinations.

CONCLUSION

A RCT assessing the consequences of active management and expectant management as well as the effect of vaginal examinations during labour for term prelabour rupture of membranes is necessary.

Active versus expectant management for premature rupture of membranes at term: A randomized, controlled study

OBJECTIVE

To compare the effects on feto-maternal outcomes of expectant versus active management for premature rupture of membranes (PROM) at term.

METHODS

This was a prospective randomized (1:1) controlled study involving 86 pregnant-women who received either expectant management (n = 43) or active management with misoprostol (n = 43) for PROM at term. Primary outcome was route of delivery. Secondary outcomes were: PROM to presentation interval; latency period; PROM to delivery interval; recruitment to delivery interval; labour and delivery complications.

RESULTS

Baseline-characteristics were similar between groups. There was no significant difference between active and expectant groups in mean PROM to presentation/admission, or PROM to delivery. However, mean latency period (11.1 ± 7.3 hours vs 8.8 ± 5.5 hours) and mean recruitment to delivery intervals after PROM (14.7 ± 5.2 hours vs 11.8 ± 5.0 hours) were significantly shorter for the active group compared with the expectant group. Although the rate of caesarean section was less in expectant management group (21%) compared with the active management group (30%), the difference was not statistically significant. There were no significant differences between groups in delivery or perinatal complications.

CONCLUSION

Active and expectant management for PROM at term gave comparable outcomes in terms of methods of delivery and complications. However, active management significantly shortened the latency period and induction to delivery intervals compared with expectant management.Trial-Registration: Pan-African-trial-registry-(PACTR)-approval-number PACTR202206797734088.

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.

ACOG Committee Opinion No. 766: Approaches to Limit Intervention During Labor and Birth

Obstetrician-gynecologists, in collaboration with midwives, nurses, patients, and those who support them in labor, can help women meet their goals for labor and birth by using techniques that require minimal interventions and have high rates of patient satisfaction. Many common obstetric practices are of limited or uncertain benefit for low-risk women in spontaneous labor. For women who are in latent labor and are not admitted to the labor unit, a process of shared decision making is recommended to create a plan for self-care activities and coping techniques. Admission during the latent phase of labor may be necessary for a variety of reasons, including pain management or maternal fatigue. Evidence suggests that, in addition to regular nursing care, continuous one-to-one emotional support provided by support personnel, such as a doula, is associated with improved outcomes for women in labor. Data suggest that for women with normally progressing labor and no evidence of fetal compromise, routine amniotomy need not be undertaken unless required to facilitate monitoring. The widespread use of continuous electronic fetal monitoring has not been shown to significantly affect such outcomes as perinatal death and cerebral palsy when used for women with low-risk pregnancies. Multiple nonpharmacologic and pharmacologic techniques can be used to help women cope with labor pain. Women in spontaneously progressing labor may not require routine continuous infusion of intravenous fluids. For most women, no one position needs to be mandated or proscribed. Obstetrician-gynecologists and other obstetric care providers should be familiar with and consider using low-interventional approaches, when appropriate, for the intrapartum management of low-risk women in spontaneous labor. Birthing units should carefully consider adding family-centric interventions that are otherwise not already considered routine care and that can be safely offered, given available environmental resources and staffing models. These family-centric interventions should be provided in recognition of the value of inclusion in the birthing process for many women and their families, irrespective of delivery mode. This Committee Opinion has been revised to incorporate new evidence for risks and benefits of several of these techniques and, given the growing interest on the topic, to incorporate information on a family-centered approach to cesarean birth.

[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).

Which method is best for the induction of labour? A systematic review, network meta-analysis and cost-effectiveness analysis

BACKGROUND

More than 150,000 pregnant women in England and Wales have their labour induced each year. Multiple pharmacological, mechanical and complementary methods are available to induce labour.

OBJECTIVE

To assess the relative effectiveness, safety and cost-effectiveness of labour induction methods and, data permitting, effects in different clinical subgroups.

METHODS

We carried out a systematic review using Cochrane methods. The Cochrane Pregnancy and Childbirth Group's Trials Register was searched (March 2014). This contains over 22,000 reports of controlled trials (published from 1923 onwards) retrieved from weekly searches of OVID MEDLINE (1966 to current); Cochrane Central Register of Controlled Trials (The Cochrane Library); EMBASE (1982 to current); Cumulative Index to Nursing and Allied Health Literature (1984 to current); ClinicalTrials.gov; the World Health Organization International Clinical Trials Registry Portal; and hand-searching of relevant conference proceedings and journals. We included randomised controlled trials examining interventions to induce labour compared with placebo, no treatment or other interventions in women eligible for third-trimester induction. We included outcomes relating to efficacy, safety and acceptability to women. In addition, for the economic analysis we searched the Database of Abstracts of Reviews of Effects, and Economic Evaluations Databases, NHS Economic Evaluation Database and the Health Technology Assessment database. We carried out a network meta-analysis (NMA) using all of the available evidence, both direct and indirect, to produce estimates of the relative effects of each treatment compared with others in a network. We developed a de novo decision tree model to estimate the cost-effectiveness of various methods. The costs included were the intervention and other hospital costs incurred (price year 2012-13). We reviewed the literature to identify preference-based utilities for the health-related outcomes in the model. We calculated incremental cost-effectiveness ratios, expected costs, utilities and net benefit. We represent uncertainty in the optimal intervention using cost-effectiveness acceptability curves.

RESULTS

We identified 1190 studies; 611 were eligible for inclusion. The interventions most likely to achieve vaginal delivery (VD) within 24 hours were intravenous oxytocin with amniotomy [posterior rank 2; 95% credible intervals (CrIs) 1 to 9] and higher-dose (≥ 50 µg) vaginal misoprostol (rank 3; 95% CrI 1 to 6). Compared with placebo, several treatments reduced the odds of caesarean section, but we observed considerable uncertainty in treatment rankings. For uterine hyperstimulation, double-balloon catheter had the highest probability of being among the best three treatments, whereas vaginal misoprostol (≥ 50 µg) was most likely to increase the odds of excessive uterine activity. For other safety outcomes there were insufficient data or there was too much uncertainty to identify which treatments performed 'best'. Few studies collected information on women's views. Owing to incomplete reporting of the VD within 24 hours outcome, the cost-effectiveness analysis could compare only 20 interventions. The analysis suggested that most interventions have similar utility and differ mainly in cost. With a caveat of considerable uncertainty, titrated (low-dose) misoprostol solution and buccal/sublingual misoprostol had the highest likelihood of being cost-effective.

LIMITATIONS

There was considerable uncertainty in findings and there were insufficient data for some planned subgroup analyses.

CONCLUSIONS

Overall, misoprostol and oxytocin with amniotomy (for women with favourable cervix) is more successful than other agents in achieving VD within 24 hours. The ranking according to safety of different methods was less clear. The cost-effectiveness analysis suggested that titrated (low-dose) oral misoprostol solution resulted in the highest utility, whereas buccal/sublingual misoprostol had the lowest cost. There was a high degree of uncertainty as to the most cost-effective intervention.

FUTURE WORK

Future trials should be powered to detect a method that is more cost-effective than misoprostol solution and report outcomes included in this NMA.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013005116.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

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.

Orally administered misoprostol for induction of labor with prelabor rupture of membranes at term

Prelabor rupture of membranes (PROM) occurs in approximately 8% to 10% of women with term pregnancies. The management of PROM continues to be controversial. Approaches include expectant management and immediate induction of labor. The use of orally administered misoprostol for the management of women with PROM may provide significant advantages when they choose immediate induction of labor. This literature review presents current evidence that supports the use of oral misoprostol for women with PROM, including the benefits of a decreased interval time from PROM to vaginal birth, good safety profile, and reductions in the use of oxytocin augmentation and epidural anesthesia. In addition to clinically proven benefits to women of oral misoprostol for PROM, it also has the potential to reduce chorioamnionitis by reducing the number of sterile vaginal examinations performed thereby reducing the risk of ascending bacteria. Women have also reported acceptability and satisfaction when using oral misoprostol for immediate induction of labor. This review of literature discusses what is known about the use of orally administered misoprostol for the management of term PROM and makes recommendations for clinical use.

Use of labour induction and risk of cesarean delivery: a systematic review and meta-analysis

BACKGROUND

Induction of labour is common, and cesarean delivery is regarded as its major complication. We conducted a systematic review and meta-analysis to investigate whether the risk of cesarean delivery is higher or lower following labour induction compared with expectant management.

METHODS

We searched 6 electronic databases for relevant articles published through April 2012 to identify randomized controlled trials (RCTs) in which labour induction was compared with placebo or expectant management among women with a viable singleton pregnancy. We assessed risk of bias and obtained data on rates of cesarean delivery. We used regression analysis techniques to explore the effect of patient characteristics, induction methods and study quality on risk of cesarean delivery.

RESULTS

We identified 157 eligible RCTs (n = 31,085). Overall, the risk of cesarean delivery was 12% lower with labour induction than with expectant management (pooled relative risk [RR] 0.88, 95% confidence interval [CI] 0.84-0.93; I(2) = 0%). The effect was significant in term and post-term gestations but not in preterm gestations. Meta-regression analysis showed that initial cervical score, indication for induction and method of induction did not alter the main result. There was a reduced risk of fetal death (RR 0.50, 95% CI 0.25-0.99; I(2) = 0%) and admission to a neonatal intensive care unit (RR 0.86, 95% CI 0.79-0.94), and no impact on maternal death (RR 1.00, 95% CI 0.10-9.57; I(2) = 0%) with labour induction.

INTERPRETATION

The risk of cesarean delivery was lower among women whose labour was induced than among those managed expectantly in term and post-term gestations. There were benefits for the fetus and no increased risk of maternal death.

Neuronal apoptosis in the neonates born to preeclamptic mothers

OBJECTIVE

Preeclampsia may result in uteroplacental insufficiency and chronic intrauterine fetal distress. The aim of this study is to address this issue investigating neuronal apoptosis in an experimental model of preeclampsia and to evaluate the neurological outcome of the perinatal asphyxia in the neonates born to preeclamptic mother.

MATERIALS AND METHODS

Two out of four pregnant Sprague-Dawley rats (preeclamptic group) were given water containing 1.8% NaCl on gestation day 15 and 22 in order to establish the model of preeclampsia whereas other two (non-preeclamptic group) received normal diet. A model of perinatal asphyxia was established on the postnatal 7th day to one preeclamptic and one non-preeclamptic dam. Overall 23 pups born to overall four dams were decapitated to assess neuronal apoptosis by the TUNEL assay.

RESULTS

The number of apoptotic neuronal cells was significantly higher in the preeclampsia groups in comparison with the control group (p = 0.006 and p = 0.006, respectively). It was also significantly higher in the asphyctic/non-preeclamptic group than the count in the control group (p = 0.01). There was also significant difference between both asphyctic groups (p = 0.003).

CONCLUSION

We conclude that preeclampsia causes small babies for the gestational age and cerebral hypoplasia. Both preeclampsia and perinatal asphyxia can cause increased neuronal apoptosis in the neonatal brains. However, the prognosis for neurological outcome is much worse when the perinatal asphyxia occurs in newborns born to preeclamptic mothers.

Midwifery Management of Prelabor Rupture of Membranes at Term

Spontaneous rupture of membranes before the onset of labor at term is commonly referred to as PROM (either premature or preterm rupture of membranes) and occurs in about 8% of term pregnancies. PROM is associated with an increased risk of infection. Many controversies exist regarding the optimal management of PROM, including the choice of induction or expectant management, use of digital vaginal exams, and routine administration of antibiotics. This article reviews the literature on PROM and illustrates some of the management issues encountered by presenting approaches used in three midwifery services.

Intravenous oxytocin alone for cervical ripening and induction of labour

BACKGROUND

Oxytocin is the commonest induction agent used worldwide. It has been used alone, in combination with amniotomy or following cervical ripening with other pharmacological or non-pharmacological methods.

OBJECTIVES

To determine the effects of oxytocin alone for third trimester cervical ripening and induction of labour in comparison with other methods of induction of labour or placebo/no treatment.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (January 2009) and bibliographies of relevant papers.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing intravenous oxytocin with placebo or no treatment, or with prostaglandins (vaginal or intracervical) for third trimester cervical ripening or labour induction.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility and carried out data extraction.

MAIN RESULTS

Sixty-one trials (12,819 women) are included.When oxytocin inductions were compared with expectant management, fewer women failed to deliver vaginally within 24 hours (8.4% versus 53.8%, risk ratio (RR) 0.16, 95% confidence interval (CI) 0.10 to 0.25). There was a significant increase in the number of women requiring epidural analgesia (RR 1.10, 95% CI 1.04 to 1.17). Fewer women were dissatisfied with oxytocin induction in the one trial reporting this outcome (5.9% versus 13.7%, RR 0.43, 95% CI 0.33 to 0.56).Compared with vaginal prostaglandins, oxytocin increased unsuccessful vaginal delivery within 24 hours in the two trials reporting this outcome (70% versus 21%, RR 3.33, 95% CI 1.61 to 6.89). There was a small increase in epidurals when oxytocin alone was used (RR 1.09, 95% CI 1.01 to 1.17).Most of the studies included women with ruptured membranes, and there was some evidence that vaginal prostaglandin increased infection in mothers (chorioamnionitis RR 0.66, 95% CI 0.47 to 0.92) and babies (use of antibiotics RR 0.68, 95% CI 0.53 to 0.87). These data should be interpreted cautiously as infection was not pre-specified in the original review protocol.When oxytocin was compared with intracervical prostaglandins, there was an increase in unsuccessful vaginal delivery within 24 hours (50.4% versus 34.6%, RR 1.47, 95% CI 1.10 to 1.96) and an increase in caesarean sections (19.1% versus 13.7%, RR 1.37, 95% CI 1.08 to 1.74) in the oxytocin group.

AUTHORS' CONCLUSIONS

Comparison of oxytocin with either intravaginal or intracervical PGE2 reveals that the prostaglandin agents probably increase the chances of achieving vaginal birth within 24 hours. Oxytocin induction may increase the rate of interventions in labour.A suggestion that for women with prelabour rupture of membranes induction with vaginal prostaglandin may increase risk of infection for mother and baby warrants further study.

Prelabor rupture of membranes at term requiring labor induction - a feature of occult fetal cephalopelvic disproportion?

AIM

To examine the maternal and neonatal characteristics related to labor outcome following induction for prelabor rupture of membranes (PROM) after 37 weeks' gestation.

METHOD

All singleton pregnancies delivered following spontaneous or induced labor after 37 weeks in four years were analyzed. Patients with labor induction for PROM comprised the study group. Outcome of labor was analyzed according to gestational age at delivery.

RESULTS

Among the 13,505 patients in the entire cohort, 1710 (12.7%) had labor induction for PROM. These women were older and heavier, were more nulliparas and had more large-for-gestational age (LGA) infants, higher rates of instrumental and cesarean deliveries, and a shorter mean gestation, but no difference in height, mean birth weight, or incidence of male infants. Multiple logistic regression analysis confirmed that labor induction was a weak but significant independent factor for cesarean delivery (aOR 1.18, 95% CI: 1.01-1.38). The rates of cesarean delivery significantly correlated with gestational age at delivery for both LGA (P<0.001) and non-LGA (P<0.001) infants, together with significantly increased birth weight.

CONCLUSION

The results suggest that a likely explanation for the cesarean delivery following labor induction for PROM at term in our population is underlying cephalopelvic disproportion.

Length of rupture of membranes in the setting of premature rupture of membranes at term and infectious maternal morbidity

OBJECTIVE

This study was undertaken to define the time thresholds of increased risk for infectious maternal morbidities with relationship to length of ruptured membranes at term.

STUDY DESIGN

We designed a retrospective cohort study of all women with premature rupture of membranes beyond 37 weeks' gestation at a single institution. Dichotomized time thresholds of length of ruptured membranes before delivery were examined in 2-hour increments using bivariate and multivariable analyses to assess the rates of chorioamnionitis and endomyometritis.

RESULTS

Among the 3841 women meeting inclusion criteria, increased rates of chorioamnionitis and endomyometritis were noted at time thresholds of 12 hours (adjusted odds ratio 2.3 [95% confidence interval, 1.2-4.4]) and 16 hours (adjusted odds ratio 2.5 [95% confidence interval, 1.1-5.6]), respectively.

CONCLUSION

We found that when length of time of ruptured membranes before delivery is examined via dichotomized time thresholds, the risks of chorioamnionitis and endomyometritis are significantly increased at 12 hours and 16 hours, respectively. These time thresholds derived from dichotomized time analyses should be considered during risk-based counseling and labor management in the setting of term premature rupture of membranes.

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

BACKGROUND

Prelabour rupture of membranes at term is managed expectantly or by elective birth, but it is not clear if waiting for birth to occur spontaneously is better than intervening.

OBJECTIVES

To assess the effects of planned early birth versus expectant management for women with term prelabour rupture of membranes on fetal, infant and maternal wellbeing.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group Trials Register (November 2004), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 4, 2004), MEDLINE (1966 to November 2004) and EMBASE (1974 to November 2004).

SELECTION CRITERIA

Randomised or quasi-randomised trials of planned early birth compared with expectant management in women with prelabour rupture of membranes at 37 weeks' gestation or more.

DATA COLLECTION AND ANALYSIS

Two review authors independently applied eligibility criteria, assessed trial quality and extracted data. A random-effects model was used.

MAIN RESULTS

Twelve trials (total of 6814 women) were included. Planned management was generally induction with oxytocin or prostaglandin, with one trial using homoeopathic caulophyllum. Overall, no differences were detected for mode of birth between planned and expectant groups: relative risk (RR) of caesarean section 0.94, 95% confidence interval (CI) 0.82 to 1.08 (12 trials, 6814 women); RR of operative vaginal birth 0.98, 95% 0.84 to 1.16 (7 trials, 5511 women). Significantly fewer women in the planned compared with expectant management groups had chorioamnionitis (RR 0.74, 95% CI 0.56 to 0.97; 9 trials, 6611 women) or endometritis (RR 0.30, 95% CI 0.12 to 0.74; 4 trials, 445 women). No difference was seen for neonatal infection (RR 0.83, 95% CI 0.61 to 1.12; 9 trials, 6406 infants). However, fewer infants under planned management went to neonatal intensive or special care compared with expectant management (RR 0.72, 95% CI 0.57 to 0.92, number needed to treat 20; 5 trials, 5679 infants). In a single trial, significantly more women with planned management viewed their care more positively than those expectantly managed (RR of "nothing liked" 0.45, 95% CI 0.37 to 0.54; 5031 women).

AUTHORS' CONCLUSIONS

Planned management (with methods such as oxytocin or prostaglandin) reduces the risk of some maternal infectious morbidity without increasing caesarean sections and operative vaginal births. Fewer infants went to neonatal intensive care under planned management although no differences were seen in neonatal infection rates. Since planned and expectant management may not be very different, women need to have appropriate information to make informed choices.

A randomized comparison of oral mifepristone to intravenous oxytocin for labor induction in women with prelabor rupture of membranes beyond 36 weeks' gestation

OBJECTIVE

This study was undertaken to compare the use of oral mifepristone with intravenous oxytocin for labor induction in women with prelabor rupture of membranes (PROM) at 36 weeks' or greater gestational age.

STUDY DESIGN

Sixty-five women with spontaneous PROM were randomly assigned to receive orally administered mifepristone or oxytocin infusion. Two hundred milligrams of mifepristone was administered, and subjects were observed for 18 hours, or intravenous oxytocin was administered.

RESULTS

Thirty-three women received mifepristone and 32 received oxytocin. The average interval from start of induction to delivery was 1194.1 +/- 568.7 minutes for mifepristone-treated subjects and 770.8 +/- 519.9 minutes for oxytocin-treated subjects ( P = .001, log-transformed data). Of 33 mifepristone-treated subjects and 32 oxytocin-treated subjects, 25 (78.1%) and 17 (51.5%), respectively, achieved successful induction (defined as vaginal delivery within 24 hours) (relative risk [RR] 0.66, 95% CI 0.45-0.96, P = .01). There was more fetal distress in the mifepristone-treated group (9 vs 2, RR 4.36, 95% CI 1.02-18.66, P = .02), and a trend toward more cesarean births (7 vs 3, RR 2.26, 95% CI 0.64-7.99, P = .19). Eleven infants of mifepristone-treated women (33.3%) and 3 infants of oxytocin-treated women (9.4%) were admitted to the neonatal intensive care unit (RR 3.56, 95% CI 1.09-11.58, P = .02).

CONCLUSION

Oral mifepristone administration 18 hours before oxytocin infusion did not improve labor stimulation in women with PROM near term, and was associated with more adverse fetal outcomes.

Prelabor rupture of the membranes at term: when to induce labor?

OBJECTIVES

To determine the significant predictors of clinical chorioamionitis and neonatal infection in patients with prelabor rupture of the membranes at term, and to apply this information to determination of optimal timing of labor induction.

STUDY DESIGN

A retrospective case control series of women at > or =37 weeks' with prelabor rupture of the membranes. The study group consisted of women with evidence of maternal or neonatal infection. Controls had no evidence of infection. Three types of management were compared. (1) Immediate induction of labor, (2) expectant management up to 24 h followed by induction of labor if still necessary, or (3) expectant management for over 24 h. Univariate and multivariate analyses were performed by stepwise logistic regression (SPSS software package). The size of the study and the control groups was calculated for a 90% power with two sided P value of 0.05 in order to demonstrate an odds ratio of 2 for expectant management (two groups: early and late) versus immediate induction of labor (132 and 279 women in the study and the control groups, respectively).

RESULTS

The rate of expectant management for over 24 h versus expectant management until 24 h followed by induction of labor when still necessary, was higher among cases than among controls ( OR = 1.84; P < 0.017; 95% CI, 1.127-3.003). Conversely, the rate of immediate induction of labor versus expectant management until 24 h followed by induction of labor when still necessary, was also higher among cases ( OR = 2.66; P < 0.001; 95% CI, 0.222-0.644).

CONCLUSION

In women with prelabor rupture of the membranes at term, the best approach is to induce labor if spontaneous labor has not begun after 24 h.

Induction of labour with a favourable cervix and/or pre-labour rupture of membranes

Premature rupture of membranes (PROM) occurs in 8% of term deliveries. In this situation labour induction with prostaglandins, compared with expectant management, results in a reduced risk of chorioamnionitis, neonatal antibiotic therapy, neonatal intensive care (NICU) admission, and increased maternal satisfaction. The use of prostaglandin is associated with an increased rate of diarrhoea and use of analgesia/anaesthesia. Compared with oxytocin, prostaglandin induction results in a lower rate of epidural use and internal fetal heart rate monitoring but a greater risk of chorioamnionitis, nausea, vomiting, more vaginal examinations, neonatal antibiotic therapy, NICU admission and neonatal infection. Women should be informed of the risks and benefits of each method of induction.Misoprostol is gaining increasing interest as an alternative induction agent. It appears to be an effective method of labour induction with term PROM. Further research is needed to identify the preferred dosage, route and interval of administration, and to assess uncommon maternal and neonatal outcomes. There has been limited research on the use of prostaglandins, including misoprostol, for induction of labour with a favourable cervix and intact membranes. Compared with intravenous oxytocin (with and without amniotomy), labour induction using vaginal prostaglandins in women with a favourable cervix (with and without PROM) results in a higher rate of vaginal delivery within 24 hours and increased maternal satisfaction. In women with a favourable cervix, artificial rupture of membranes followed by oral misoprostol has similar time to vaginal delivery compared with artificial rupture of membranes followed by oxytocin. Further research with prostaglandins, including misoprostol, is needed to evaluate other maternal and neonatal outcomes in women being induced with a favourable cervix. No form of prostaglandin induction in women with PROM or favourable cervix has proven clearly superior to oxytocin infusion.

Prevalence and risk factors for prelabor rupture of the membranes (PROM) at or near-term in an urban Swedish population

AIMS

To determine the prevalence, recurrence rate and to identify risk factors for prelabor rupture of the membranes (PROM) after 34 completed weeks in an urban Swedish population.

METHODS

In a retrospective cohort study a sample of 2880 women aged 25-41 years, resident in the city of Göteborg, was randomly selected from the population register. According to information from the national Medical Birth Register (MBR), 1507 of these 2880 women had given birth 2736 times. 2270 of these deliveries had occurred in hospitals in the city of Göteborg and case records for 2242 of these deliveries were found. The case records were systematically analyzed for the occurrence of PROM and potential risk factors for PROM. 2208 of these deliveries occurred after 34 weeks of gestation. The further analyses were based on these 2208 deliveries.

RESULTS

The prevalence of PROM after 34 week of gestation in this urban Swedish population was 12.9% and about 20% of the women in the population had experienced PROM at least once. In the multiple stepwise regression analysis, risk factors for PROM were primiparity, premature contractions, PROM in a previous pregnancy and bleeding in the first trimester.

CONCLUSIONS

PROM is a common complication at or near term. The risk factors for PROM found in this representative study are difficult to influence and thus provide no guidance about how pregnancies should be managed to reduce the occurrence of PROM in the future.

Intravenous oxytocin alone for cervical ripening and induction of labour

BACKGROUND

Oxytocin is the commonest induction agent used worldwide. It has been used alone, in combination with amniotomy or following cervical ripening with other pharmacological or non-pharmacological methods. Prior to the introduction of prostaglandin agents oxytocin was used as a cervical ripening agent as well. In developed countries oxytocin alone is more commonly used in the presence of ruptured membranes whether spontaneous or artificial. In developing countries where the incidence of HIV is high, delaying amniotomy in labour reduces vertical transmission rates and hence the use of oxytocin with intact membranes warrants further investigation. This review will address the use of oxytocin alone for induction of labour. Amniotomy alone or oxytocin with amniotomy for induction of labour has been reviewed elsewhere in the Cochrane Library. Trials which consider concomitant administration of oxytocin and amniotomy will not be considered. This is one of a series of reviews of methods of cervical ripening and labour induction using a standardised methodology.

OBJECTIVES

To determine the effects of oxytocin alone for third trimester cervical ripening or induction of labour in comparison with other methods of induction of labour or placebo/no treatment.

SEARCH STRATEGY

The Cochrane Pregnancy and Childbirth Group Trials Register, the Cochrane Controlled Trials Register and bibliographies of relevant papers. Last searched: May 2001.

SELECTION CRITERIA

The criteria for inclusion included the following: (1) clinical trials comparing vaginal prostaglandins used for third trimester cervical ripening or labour induction with placebo/no treatment or other methods listed above it on a predefined list of labour induction methods; (2) random allocation to the treatment or control group; (3) adequate allocation concealment; (4) violations of allocated management not sufficient to materially affect conclusions; (5) clinically meaningful outcome measures reported; (6) data available for analysis according to the random allocation; (7) missing data insufficient to materially affect the conclusions.

DATA COLLECTION AND ANALYSIS

A strategy was developed to deal with the large volume and complexity of trial data relating to labour induction. This involved a two-stage method of data extraction. The initial data extraction was done centrally, and incorporated into a series of primary reviews arranged by methods of induction of labour, following a standardised methodology. The data is to be extracted from the primary reviews into a series of secondary reviews, arranged by category of woman.

MAIN RESULTS

In total, 110 trials were considered; 52 have been excluded and 58 included examining a total of 11,129 women. Comparing oxytocin alone with expectant management: Oxytocin alone reduced the rate of unsuccessful vaginal delivery within 24 hours when compared with expectant management (8.3% versus 54%, relative risk (RR) 0.16, 95% confidence interval (CI) 0.10,0.25) but the caesarean section rate was increased (10.4% versus 8.9%, RR 1.17, 95% CI 1.01,1.36). This increase in caesarean section rate was not apparent in the subgroup analyses. Women were less likely to be unsatisfied with induction rather than expectant management, in the one trial reporting this outcome (5.5% versus 13.7%, RR 0.43, 95% CI 0.33, 0.56). Comparing oxytocin alone with vaginal prostaglandins: Oxytocin alone was associated with an increase in unsuccessful vaginal delivery within 24 hours (52% versus 28%, RR 1.85, 95% CI 1.41, 2.43), irrespective of membrane status, but there was no difference in caesarean section rates (11.4% versus 10%, RR 1.12, 95% CI 0.95, 1.33). Comparing oxytocin alone with intracervical prostaglandins: Oxytocin alone was associated with an increase in unsuccessful vaginal delivery within 24 hours when compared with intracervical PGE2 (51% versus 35%, RR 1.49, 95% CI 1.12,1.99). For all women with an unfavourable cervix regardless of membrane status, the caesarean section rates were increased (19.0% versus 13.1%, RR 1.42, 95% CI 1.11, 1.82).

REVIEWER'S CONCLUSIONS

Overall, comparison of oxytocin alone with either intravaginal or intracervical PGE2 reveals that the prostaglandin agents probably overall have more benefits than oxytocin alone. The amount of information relating to specific clinical subgroups is limited, especially with respect to women with intact membranes. Comparison of oxytocin alone to vaginal PGE2 in women with ruptured membranes reveals that both interventions are probably equally efficacious with each having some advantages and disadvantages over the others. With respect to current practice in women with ruptured membranes induction can be recommended by either method and in women with intact membranes there is insufficient information to make firm recommendations.

Oxytocin for prelabour rupture of membranes at or near term

BACKGROUND

Induction of labour after prelabour rupture of membranes may reduce the risk of neonatal infection.

OBJECTIVES

The objective of this review was to assess the effects of induction of labour with oxytocin versus expectant management for prelabour rupture of membranes at or near term (34 weeks or more).

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register.

SELECTION CRITERIA

Randomised and quasi-randomised trials of early use of oxytocin versus no early use of oxytocin for spontaneous rupture of membranes, before labour (34 weeks gestation or more).

DATA COLLECTION AND ANALYSIS

Trials were assessed for quality and data were abstracted.

MAIN RESULTS

Eighteen studies were included. The trials were of variable quality with potential for significant bias. Compared to expectant management, induction of labour by oxytocin was associated with a decreased risk of maternal infection (odds ratio for chorioamnionitis of 0.63, 95% confidence interval 0.51 to 0.78, endometritis 0.72, 95% confidence interval 0.52 to 0.99). There was also a decreased risk of neonatal infection (odds ratio 0.64, 95% confidence interval 0.44 to 0.93). The size of this effect may have been biased in favour of oxytocin. Based on one trial, women were more likely to view their care positively if labour was induced with oxytocin. Caesarean section rates were not statistically different between groups, although the trend was towards fewer interventions with expectant management. Oxytocin was associated with more frequent use of pain relief and internal fetal heart rate monitoring. Perinatal mortality rates were low and not significantly different between groups, although the trend was towards fewer deaths with induction of labour by oxytocin.

REVIEWER'S CONCLUSIONS

Induction of labour by oxytocin may decrease the risk of maternal and neonatal infection compared to expectant management. Induction of labour with oxytocin does not appear to increase the rate of caesarean section, although it may increase use of pain relief and internal fetal heart rate monitoring.

Prelabour rupture of the membranes at term--no advantage of delaying induction for 24 hours

We performed a prospective randomized study to compare maternal and fetal outcomes in pregnancies with prelabour rupture of the membranes (PROM) at term with early induction of labour or expectant management, 126 women with singleton pregnancy, cephalic presentation and gestational duration > or = 37 weeks, were randomized either to immediate induction of labour with oxytocin (Group 1) (n=52), or conservative management (Group 2) (n=74). Women who constituted Group 2 were divided into 2 groups. The first group (Group 2A) (n=25) included women in whom spontaneous labour did not begin after a waiting period of 24 hours, in which case labour was induced with oxytocin i.e. expectant management. The second group consisted of women (Group 2B) (n=49) in whom labour began spontaneously within 24 hours. The base Caesarean section rate was significantly higher in Group 2 (28.4%) (p<0.05). The rates of Caesarean section in the Groups 1-2A-2B were 19.2%, 60%, and 12.2%, respectively for nulliparous and parous women together. The rate of fetal distress was significantly higher in Group 2 (p<0.05). For determining maternal outcomes, the other parameters such as clinical chorioamnionitis, fever before or during labour, receiving antibiotics before or during labour, postpartum fever, analgesia, anaesthesia did not differ in Groups 1 and 2. Women in Group 1 went into active labour sooner, had fewer digital vaginal examinations, had a shorter interval between membrane rupture and delivery, and spent less time in the hospital before delivery than those in Group 2 (p<0.05). Babies in Group 2 were more likely to receive antibiotics, and more likely to stay in an intensive care nursery for more than 24 hours, and more likely to receive ventilation after initial resuscitation than those babies in Group 1. For developing apnoea and hypotonia, there was no significant difference between Groups 1 and 2. However, for babies in Group 2A there was a significant difference. We conclude that immediate induction of labour with oxytocin does not increase the risk of Caesarean section, compared with a practice of expectant management. Women at term with prelabour rupture of the membranes should therefore be reassured that immediate induction with oxytocin currently appears to be the best policy with respect to maternal and neonatal morbidity.

Risk factors for neonatal sepsis in offspring of women with prelabor rupture of the membranes at 34-42 weeks

One thousand three hundred eighty-five women with PROM (prelabor rupture of the membranes) participated in a prospective randomized study. Women with PROM were randomized to induction the following morning after PROM (early induction group) or induction two days later (late induction group). If contractions started within 2 hours after admission these women were included in the short latency group. All neonatal infections were classified as verified sepsis (positive culture) or clinical sepsis. The aim of the study was to compare the perinatal infectious outcome between the groups with different expectant managements in women with PROM and to study the association between demographic, intrapartum and postpartum variables and neonatal sepsis. In the short latency group one neonate had a proven sepsis while four neonates with proven sepsis were found in the early induction group. No proven sepsis was detected in the late induction group. Univariate analyses showed a significant association between clinical sepsis and: induction of labor (OR = 2.94, 95% CI 1.30-6.68), established labor 24.1-32 hours after ROM (OR = 5.89, 95% CI 1.68-20.63), established labor > 32 hours after ROM (OR = 4.59, 95% CI 1.52-13.87), time from ROM to delivery > 32 hours (OR = 5.07, 95% CI 1.40-18.39), cesarean section (OR = 11.03, 95% CI 4.10-29.68), chorioamnionitis before or during delivery (OR = 27.14, 95% CI 2.38-309.16), endometritis (OR = 18.08, 95% CI 1.82-179.87), CRP over 20 mg/l in the umbilical cord (OR = 17.12, 95% CI 5.68-52.12) and Apgar score < 7 after 1, 5 or 10 minutes. In a stepwise logistic regression analysis a significant association was found between clinical sepsis and cesarean section (OR = 10.08, 95% CI = 3.26-31.20), time from ROM to delivery > 32 h (OR = 3.74, 95% CI 1.62-8.62), gestational age 34-36 weeks (OR = 3.16, 95% CI 1.11-8.96) and parous women (OR = 2.41, 95% CI 1.04-5.57). In conclusion, this study indicates that that there was no difference in the incidence of neonatal infections between those with early and late induction. Clinical neonatal sepsis was associated with time from PROM to delivery over 32 hours, cesarean section, parous women and gestational age between 34 and 36 weeks.

Induction of labor with misoprostol for premature rupture of membranes beyond thirty-six weeks' gestation

OBJECTIVE

Our purpose was to compare vaginally administered misoprostol (Cytotec) with intravenous oxytocin for labor induction in women with premature rupture of membranes beyond 36 weeks' gestation.

STUDY DESIGN

Two hundred subjects with rupture of membranes without labor were randomly assigned to receive vaginally administered misoprostol or intravenous oxytocin. Twenty-five micrograms of misoprostol (Cytotec) was placed in the posterior vaginal fornix. If cervical ripening (Bishop score of > or = 8 or cervical dilatation of > or = 3 cm) or active labor did not occur, a single repeat dose of misoprostol was given 6 hours later. Oxytocin was administered intravenously by a standardized incremental infusion protocol to a maximum dose of 22 mU per minute.

RESULTS

Of the 197 subjects evaluated, 98 received misoprostol and 99 oxytocin. The average interval from start of induction to vaginal delivery was about 1 hour longer in the misoprostol group (811.5 +/- 511.4 minutes) than in the oxytocin group (747.0 +/- 448.0 minutes) (P = .65, log transformed data). Oxytocin administration was necessary in 37 of 98 (37.8%) of misoprostol-treated subjects. Vaginal delivery occurred in 85 misoprostol-treated subjects (86.7%) and 82 (85.9%) oxytocin-treated subjects (relative risk 1.17, 95% confidence interval 0.78 to 1.78, P = .45) with the remainder undergoing cesarean birth. There was no difference in the incidence of tachysystole (six or more uterine contractions in a 10-minute window for two consecutive 10-minute periods) or hypertonus between the two groups. There was no significant difference in frequency of abnormal fetal heart rate tracings between the two groups (29.6% in the misoprostol group and 28.9% in the oxytocin group, P = .91). Chorioamnionitis was diagnosed in 28 (28.6%) misoprostol-treated subjects and 26 (26.3%) oxytocin-treated subjects (P = .72, relative risk 1.06, 95% confidence interval 0.78 to 1.45). No significant differences were found in the incidence of fetal meconium (8.1% and 9.1%), 1- or 5-minute Apgar scores < 7 (11.0% and 10.2% of 1-minute Apgar scores, and 2.0% and 2.0% of 5-minute Apgar scores), neonatal resuscitation (24.5% and 27.6%), or admission to the neonatal intensive care unit (25.5% and 32.3%) between the two groups.

CONCLUSIONS

Vaginal administration of misoprostol (Cytotec) is an effective alternative to oxytocin infusion for labor induction in women with premature rupture of the membranes near term. The incidence of untoward effects is similar with use of the two agents.

Prelabour rupture of membranes at term: early induction of labour versus expectant management

OBJECTIVES

To compare expectant management with early induction of labour in pregnant patients with prelabour rupture of membranes at term and unfavourable cervix.

STUDY DESIGN

A prospective, randomised study of 154 women with prelabour rupture of membranes at term of whom 80 had been managed expectantly, and 74 had undergone oxytocin induction at a rate of 2.5 mU/min. Digital examination was not performed before oxytocin infusion, and the first was delayed until 4 h (nulliparae), or 2 h (multiparae) of regular uterine contractions.

RESULTS

The mean period from rupture of membranes to delivery was significantly shorter in the induction group. The mean duration of labour was significantly shorter in the expectant group. Operative vaginal deliveries were more common in the induction group, and fetal distress was the most common cause of operative vaginal deliveries. The caesarean rates were low and similar in both groups. Maternal and neonatal infectious morbidity was similar and no difference was found in the length of hospitalisation.

CONCLUSIONS

Expectant management in patients with ruptured membranes at term is safe and reduces the frequency of operative vaginal deliveries.

Premature rupture of the membranes in term patients

Premature rupture of the membranes (PROM) occurs in 5-10% of pregnancies. Approximately 60% of cases are in term patients. Infection of the lower genital tract and/or amniotic cavity is one of the most important etiologies of PROM. The diagnosis is usually established by direct observation of pooling of amniotic fluid in the vaginal vault. In problematic cases, the nitrazine and fern tests can be used to confirm the diagnosis. Term patients with PROM and favorable cervices should undergo induction of labor with oxytocin. Patients with unfavorable cervices probably are best managed by induction of labor with prostaglandin compounds, although, in highly selected cases, expectant management may be considered. During induction of labor, long latent phases should be anticipated, and vaginal examinations should be minimized. Patients should receive prophylactic antibiotics, if indicated, for prevention of group B streptococcal infection and should be observed carefully for early signs of chorioamnionitis.

A randomised trial of two expectant managements of prelabour rupture of the membranes at 34 to 42 weeks

OBJECTIVE

To compare obstetric and perinatal outcome between two different expectant managements in women with prelabour rupture of the membranes (PROM).

DESIGN

A randomised study.

PARTICIPANTS

One thousand three hundred and eighty-five women with rupture of the membranes at 34 to 42 weeks without contractions.

INTERVENTIONS

Women without contractions 2 h after admission were randomised to early induction the following morning after PROM (early induction group) or induction two days later (late induction group). Women with contractions starting within 2 h after admission were included in the calculations as a short latency group. Digital examinations of the cervix were avoided until onset of active labour. Labour was induced with oxytocin in both groups if no spontaneous contractions occurred or if chorioamnionitis or fetal distress was detected.

MAIN OUTCOME MEASURES

The frequency of spontaneous deliveries, operative deliveries, maternal and neonatal infections.

RESULTS

In nulliparous women, a higher rate of spontaneous deliveries was found in the late induction group (89%) compared with the early induction group (81%) (P < 0.05). The ventouse extraction rate was 7% and 14% respectively (P < 0.05). A low (2-4%) caesarean section rate was recorded and did not differ between the groups. Endometritis was detected in six women after delivery. Sixty-one children were treated with antibiotics, and no difference could be detected between the groups.

CONCLUSIONS

A higher rate of spontaneous deliveries was found among nulliparous women with prolonged latency as compared with brief latency prior to induction. A protocol of no digital examination before labour was associated with infrequent maternal and fetal morbidity, regardless of latency.

Induction of labor compared with expectant management for prelabor rupture of the membranes at term. TERMPROM Study Group

BACKGROUND

As the interval between rupture of the fetal membranes at term and delivery increases, so may the risk of fetal and maternal infection. It is not known whether inducing labor will reduce this risk or whether one method of induction is better then another.

METHODS

We studied 5041 women with prelabor rupture of the membranes at term. The women were randomly assigned to induction of labor with intravenous oxytocin; induction of labor with vaginal prostaglandin E2 gel; or expectant management for up to four days, with labor induced with either intravenous oxytocin or vaginal prostaglandin E2 gel if complications developed. The primary outcome was neonatal infection. Secondary outcomes were the need for cesarean section and women's evaluations of their treatment.

RESULTS

The rates of neonatal infection and cesarean section were not significantly different among the study groups. The rates of neonatal infection were 2.0 percent for the induction-with-oxytocin group, 3.0 percent for the induction-with-prostaglandin group, 2.8 percent for the expectant-management (oxytocin) group, and 2.7 percent for the expectant-management (prostaglandin) group. The rates of cesarean section ranged from 9.6 to 10.9 percent. Clinical chorioamnionitis was less likely to develop in the women in the induction-with-oxytocin group than in those in the expectant-management (oxytocin) group (4.0 percent vs. 8.6 percent, P<0.001), as was postpartum fever (1.9 percent vs. 3.6 percent, P=0.008). Women in the induction groups were less likely to say they liked "nothing" about their treatment than those in the expectant-management groups.

CONCLUSIONS

In women with prelabor rupture of the membranes at term, induction of labor with oxytocin or prostaglandin E2 and expectant management result in similar rates of neonatal infection and cesarean section. Induction of labor with intravenous oxytocin results in a lower risk of maternal infection than does expectant management. Women view induction of labor more positively than expectant management.

Induction of labour: a randomised clinical trial of amniotomy versus amniotomy with oxytocin infusion

OBJECTIVE

To compare two methods of induction of labour-amniotomy with oxytocin infusion versus amniotomy alone.

DESIGN

Prospective randomised clinical trial.

SETTING

The department of obstetrics in a Swedish central hospital.

PARTICIPANTS

One hundred and ninety-six pregnant women with indication for induction of labour at term and a favourable cervix (modified Bishop score > or = 6).

INTERVENTIONS

The women were randomised to amniotomy followed by oxytocin infusion after 1 h (group A, n = 98) or amniotomy alone (group B, n = 98). If labour had not ensued on the following morning, after approximately 24 h, the women in group B were given an oxytocin infusion.

MAIN OUTCOME MEASURES

Induction-delivery interval, duration of labour, time spent in delivery ward, oxytocin use, maternal and neonatal clinical outcome.

RESULTS

Amniotomy combined with early oxytocin infusion resulted in shorter induction-delivery interval (median 6.0 h; 95% confidence interval (CI) 5.0 to 6.5 h) than amniotomy alone (median 9.0 h; 95% CI 7.5 to 10.0 h). This was due to a shorter latent period in the former group (median 2.3 h; 95% CI 2.0 to 3.0 h) compared to the latter (median 4.3 h; 95% CI 3.0 to 5.5 h). The duration of labour stages 1 and 2 were similar in both groups. The time spent in the delivery ward was slightly reduced for women managed by amniotomy alone (median 5.0 h; 95% CI 4.5 to 6.0 h) compared with those managed by the combination of amniotomy and oxytocin infusion (median 6.0 h; 95% CI 5.0 to 6.5 h). Eighty-seven percent in group A and 32% in group B were given oxytocin, and the total oxytocin infusion time was nearly five times longer in group A. No other important effect on maternal or fetal outcomes was demonstrated.

CONCLUSION

With regard to safety the results do not warrant recommending either type of labour induction. The minor differences observed between the induction groups justify an individual management policy, with attention paid to both the indication for induction of labour and the woman's choice.

Controlled comparison of induction versus expectant care for prelabor rupture of the membranes at term

This randomized clinical trial compared oxytocin induction of labor with expectant care for 48 hours after prelabor rupture of the membranes at term. Women at term with prelabor rupture of the membranes for at least 8 hours were assigned at random to induction with oxytocin or to expectant management for 48 hours followed by induction if necessary. Of 168 eligible women, 123 (73%) agreed to participate. More women in the induction group (23%) than in the expectant group (10%) had operative delivery, either cesarean section or instrumental vaginal delivery. In the induction group 41% received analgesia versus 24% in the expectant group (p < 0.005). There was no difference in the rate of maternal and neonatal infection between groups and sepsis was not observed. The active policy of oxytocin induction exposed the mother to a higher risk of operative delivery and a less comfortable labor than the 48 hours expectant care option.

Controversies: the mature breech should be delivered by elective cesarean section

The fetal hazards of vaginal breech delivery have been recognised for centuries. In recent years the increased safety of Cesarean delivery has prompted a steady rise in its use for the delivery of the term breech fetus. In many maternity units more than 90% of breech babies are delivered in this way. In contrast some obstetricians argue that with appropriate selection criteria, safe, selective, vaginal breech delivery is possible. This argument is not supported by population studies, which indicate that perinatal mortality and morbidity rates associated with attempts at vaginal breech delivery are between 1-2%.