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

Vaginal prostaglandin (PGE2 and PGF2a) for induction of labour at term

BACKGROUND

Prostaglandins have been used for induction of labour since the 1960s. Initial work focused on prostaglandin F2a as prostaglandin E2 was considered unsuitable for a number of reasons. With the development of alternative routes of administration, comparisons were made between various formulations of vaginal prostaglandins. This is one of a series of reviews of methods of cervical ripening and labour induction using standardised methodology.

OBJECTIVES

To determine the effects of vaginal prostaglandins E2 and F2a for third trimester cervical ripening or induction of labour in comparison with placebo/no treatment or other vaginal prostaglandins (except misoprostol).

SEARCH STRATEGY

The Cochrane Pregnancy and Childbirth Group trials register (May 2003) and bibliographies of relevant papers.

SELECTION CRITERIA

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.

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.

MAIN RESULTS

In total, 101 studies were considered: 43 excluded and 57 (10,039 women) included. One study is awaiting assessment. Vaginal prostaglandin E2 compared with placebo or no treatment reduced the likelihood of vaginal delivery not being achieved within 24 hours (18% versus 99%, relative risk (RR) 0.19, 95% confidence interval (CI) 0.14 to 0.25, 2 trials, 384 women), there was no evidence of a difference between caesarean section rates although the risk of uterine hyperstimulation with fetal heart rate changes was increased (4.6% versus 0.51%, RR 4.14, 95% CI 1.93 to 8.90, 13 trials, 1203 women). Comparison of vaginal prostaglandin F2a with placebo showed similar caesarean section rates but the cervical score was more likely to be improved (15% versus 60%, RR 0.25, 95% CI 0.13 to 0.49, 5 trials, 467 women), and the risk of oxytocin augmentation reduced (53.9% versus 89.1%, RR 0.60, 95% CI 0.43 to 0.84, 11 trials, 1265 women) with the use of vaginal PGF2a. There were insufficient data to make meaningful conclusions for the comparison of vaginal PGE2 and PGF2a.PGE2 tablet, gel and pessary appear to be as efficacious as each other. Lower dose regimens, as defined in the review, appear as efficacious as higher dose regimens.

REVIEWER'S CONCLUSIONS

The primary aim of this review was to examine the efficacy of vaginal prostaglandin E2 and F2a. This is reflected by an increase in successful vaginal delivery rates in 24 hours, no increase in operative delivery rates and significant improvements in cervical favourability within 24 to 48 hours. Further research is needed to quantify the cost-analysis of induction of labour with vaginal prostaglandins, with special attention to different methods of administration.

Active management of term prelabour rupture of membranes with oral misoprostol

OBJECTIVE

To compare the active management of term prelabour rupture of membranes with oral misoprostol with conservative management for 24 hours followed by induction with oxytocin or prostaglandin E(2) (PGE(2)) gel.

DESIGN

A non-blinded randomised controlled trial.

SETTING

Induction and labour wards, Aberdeen Maternity Hospital.

POPULATION

Sixty-one women with confirmed prelabour rupture of the membranes at > or =36 weeks of gestation.

METHODS

The women were randomised to 50 microg of oral misoprostol repeated every 4 hours, if required, to a maximum of five doses (active group), or to induction of labour with PGE(2) gel or oxytocin only if not in spontaneous labour 24 hours after prelabour rupture of membranes (conservative group).

MAIN OUTCOME MEASURES

Number of women in active labour within 24 hours of the prelabour rupture of membranes, preference of women for any one particular method of management in any subsequent pregnancy with prelabour rupture of membranes.

RESULTS

93.3% of the active group and 54.8% of the conservative group were in spontaneous labour within 24 hours of the prelabour rupture of membranes (RR 1.7, 95% CI 1.2 to 2.4). Of those achieving a vaginal delivery, 72% of the active group did so within 24 hours of the prelabour rupture of membranes as compared with 26.9% of the conservative group (RR 2.7, 95% CI 1.4 to 5.3, P = 0.002). There were no significant differences in the neonatal or maternal outcomes. In the active group, 78% felt they would have the same method of induction as compared with 40% in the conservative group (RR 1.9, 95% CI 1.1 to 3.3, P = 0.03).

CONCLUSIONS

Active management with oral misoprostol resulted in more women going into labour and delivering within 24 hours of the prelabour rupture of membranes with no increase in maternal or neonatal complications. Women tended to view active management of prelabour rupture of membranes more positively. Oral misoprostol might be an option to consider in those wishing active management.

The effect of the publication of a major clinical trial in a high impact journal on clinical practise: the ORACLE Trial experience

OBJECTIVE

To estimate the short term effect of the publication of a major clinical trial on clinical practise.

DESIGN

Questionnaire survey of clinical practise.

SETTING

UK.

POPULATION

All maternity units in the UK.

METHOD

A self-administered questionnaire completed by lead consultants on delivery suite of maternity units.

MAIN OUTCOME MEASURES

Changes in antibiotic prescription.

RESULTS

Within six months of publication, approximately 50% of maternity units had changed their guidelines for the care of women with preterm prelabour rupture of the fetal membranes.

CONCLUSION

Publication of a major clinical trial does impact on clinical practise but the impact is heterogeneous in terms of time and consistency.

Differences in management and results in term-delivery in nine European referral hospitals: descriptive study

OBJECTIVE

To compose obstetric interventions around Europe.

STUDY DESIGN

A survey of obstetric practices, logistics and statistical outcomes in nine tertiary referral hospitals in Europe between November 1999 and October 2000.

RESULTS

There was wide variation in the management of pre labour rupture of the membranes at term, methods of analgesia, induction of labour, and mode of cephalic and breech delivery. Midwives practised normal deliveries at only three sites. Rates of epidural analgesia varied from 0% in Perugia to 98% in Barcelona, instrumental delivery from 3% in Perugia to 40% in Barcelona, episiotomy from 9.7% in Uppsala to 58% in Perugia, caesarean section before and during labour from 12% in Paris to 32% in Athens, vaginal breech delivery from 15% in Barcelona to 70% in Paris. The percentage of primipara varied from 40% in Uppsala to 65% in Perugia; birth weight under 2500g from 5% in Uppsala to 23% in Amsterdam, over 4000g from 3.1% in Athens to 22% in Uppsala and gestational age less than 37 weeks from 6% in Dublin to 26% in Amsterdam.

CONCLUSION

There are considerable differences in obstetric practices without any major difference in maternal and perinatal mortality.

Crossing international boundaries: implications for the Term Breech Trial Data Coordinating Centre

The Term Breech Trial (TBT) is a multicenter, international randomized trial that compared a policy of planned cesarean section with a policy of planned vaginal birth for selected pregnancies with a fetus in breech presentation at term. The TBT involved 121 centers in 26 countries that recruited 2088 women between January 9, 1997 and April 21, 2000. This paper briefly describes the impact of broad international collaboration on data coordinating center activities, including center selection, obtaining ethics approvals, data management, center funding, and recruitment.

Antibiotics for prelabour rupture of membranes at or near term

BACKGROUND

Prelabour rupture of the membranes at or near term (term PROM) increases the risk of infection for the woman and her baby. The routine use of antibiotics for women at the time of term PROM may reduce this risk. However, due to increasing problems with bacterial resistance and the risk of maternal anaphylaxis with antibiotic use, it is important to assess the evidence addressing risks and benefits in order to ensure judicious use of antibiotics. This review was undertaken to assess the balance of risks and benefits to the mother and infant of antibiotic prophylaxis for prelabour rupture of the membranes at or near term.

OBJECTIVES

To assess the effects of antibiotics administered prophylactically to women with prelabour rupture of the membranes at 36 weeks or beyond, on maternal, fetal and neonatal outcomes.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's specialised register of controlled trials (October 2001), the Cochrane Controlled Trials Register (The Cochrane Library, Issue 4, 2001), MEDLINE (1965 to 2001). Other sources included contacting recognised experts and cross referencing relevant material.

SELECTION CRITERIA

All randomised trials which compared outcomes for women and infants when antibiotics were administered prophylactically for prelabour rupture of the membranes at or near term, with outcomes for controls (placebo or no treatment).

DATA COLLECTION AND ANALYSIS

Assessment of trial quality and data extraction were undertaken independently by the two authors who then compared and resolved differences. Additional data were received from the investigators of included trials. Meta-analysis was undertaken using a fixed effects model and results are presented using relative risk (RR), risk difference (RD) and number needed to treat (NNT) (where appropriate) for categorical data, and mean difference (MD) for variables measured on a continuous scale. All results are presented with 95% confidence intervals (CI).

MAIN RESULTS

The results of two trials, involving a total of 838 women, are included in this review. The use of antibiotics resulted in a statistically significant reduction in maternal infectious morbidity (chorioamnionitis or endometritis): RR 0.43 (95% CI 0.23, 0.82), RD -4% (95% CI -7%, -1%), NNT 25 (95% CI 14 -100). No statistically significant differences were shown for outcomes of neonatal morbidity.

REVIEWER'S CONCLUSIONS

No clear practice recommendations can be drawn from the results of this review on this clinically important question, related to a paucity of reliable data. Further well designed randomised controlled trials are needed to assess the effects of routine use of maternal antibiotics for women with prelabour rupture of the membranes at or near term.

Management of premature rupture of membranes

The management of patients with PROM, regardless of gestational age, remains controversial. Generally, when patients are in labor, have infection, or there is irreversible fetal distress, there are few options other than delivery. For those not in labor, especially in premature gestational ages, the complexities of the many combinations of decisions to be made regarding the best methods for evaluating patients, prolonging gestation, reducing complications of prematurity, and choosing the timing and route of delivery make studying and solving the problem of the best option for management difficult at best. The administration of corticosteroids and broad-spectrum antibiotics of those patients in the very early premature gestational age groups has now been shown clearly to improve outcome. Beyond that, the remainder of these problems are somewhat unresolved and several reasonable options often exist and are likely to remain so for some time to come.

The relationship between cervical dilatation at initial presentation in labour and subsequent intervention

OBJECTIVE

To examine the relationship between the cervical dilatation at which women present in labour and the subsequent likelihood of caesarean section.

DESIGN

Retrospective cohort study.

SETTING

University teaching hospital.

POPULATION

3,220 women met the entry criteria from 14,050 deliveries between January 1995 and December 1999.

METHODS

Women meeting the following criteria were identified: those in spontaneous labour with a singleton pregnancy and a cephalic presentation at 37-42 weeks of gestation; all women delivering within 36 hours of first presentation were included. Women who had spontaneous rupture of the membranes before first attendance were excluded.

MAIN OUTCOME MEASURES

The primary outcome was the rate of caesarean section. Secondary outcomes were operative vaginal delivery, fetal weight, cord pH, five minute Apgar score, length of labour, labour augmentation with oxytocin and epidural analgesia.

RESULTS

The risk of caesarean section decreased with increasing cervical dilatation at presentation. This was true for nulliparous (n = 1,168) and parous women (n = 2,052). The caesarean section rate of nulliparous women presenting at 0-3cm (n = 812) was 10.3%, compared with 4.2% for those presenting at 4cm-10 cm (n = 356), and the mean duration of labour before presentation was 2.0 hours versus 4.5 hours, respectively (P = 0.0001). For parous women the caesarean section rates were 5.7% and 1.3%, respectively (P = 0.0001). There were significantly greater frequencies of use of oxytocin and epidural analgesia by women presenting earlier in labour. The caesarean section rate of 185 nulliparae (15.8%) who were initially allowed home was no different from those admitted immediately (9.2% vs 8.2%, P = 0.67). Similarly, 196 (9.5%) of multiparae went home and had a caesarean section rate of 3.6%, compared with 3.1% if admitted immediately (P = 0.76).

CONCLUSIONS

Women who present to hospital at 0-3cm spend less time in labour before presentation and are more likely to have obstetric intervention than those presenting in more advanced labour. Outcomes were similar whether or not the woman was initially allowed home.

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.

Temporal changes in rates and reasons for medical induction of term labor, 1980-1996

OBJECTIVE

This study was undertaken to assess temporal changes in rates and reasons for medical induction of term labor.

STUDY DESIGN

A retrospective medical record review was conducted on a population-based cohort of 1293 women with term deliveries.

RESULTS

The rate of medical labor induction increased from 12.9% in 1980 to 25.8% in 1995. Stated indications also changed, with a 2-fold increase in induction for postdate gestation, a 23-fold increase in induction for macrosomia, a 15-fold increase in elective induction, and a 22-fold decline in induction for premature rupture of membranes. The average gestational age at delivery of postdate pregnancies declined from 41.9 weeks in 1980 to 41.0 weeks in 1995. By 1995, the average maternal length of stay and the percentage of cesarean deliveries were higher among women with induced labor at term than among those with spontaneous labor at term.

CONCLUSION

Induction of term labor has almost doubled in prevalence during the past 15 years. The most common indications are elective induction and postdate pregnancy, often applied to gestations of 40 to 41 weeks' duration.

Oral misoprostol vs. placebo in the management of prelabor rupture of membranes at term

OBJECTIVE

To evaluate the efficacy of oral misoprostol for the induction of labor (IOL) in women with prelabor rupture of membranes at term (PROM) and to monitor maternal or fetal complications.

METHOD

This randomized, placebo controlled trial was performed in a secondary referral hospital. The data of 47 patients in the misoprostol--and 49 patients in the placebo group was available for analysis. The former received 100 microg misoprostol orally, repeated once after 6 h if not in active labor, the latter received two doses of vitamin C also after a 6-h interval. The Mann-Whitney U-test was used for analysis.

RESULTS

The median treatment to delivery interval in the misoprostol group was 7.5 h and 25 h in the placebo group (P<0.001). No significant differences were found in the incidence of abnormalities on the cardiotocograph, mode of delivery, neonatal outcome, use of antibiotics for the mothers and patient acceptability.

CONCLUSION

Oral misoprostol in the suggested dose is an effective and cheap alternative for IOL in patients with PROM. No adverse effects could be demonstrated.

Evolution of treatment effects over time: empirical insight from recursive cumulative metaanalyses

Evidence on how much medical interventions work may change over time. It is important to determine what fluctuations in the treatment effect reported by randomized trials and their metaanalyses may be expected and whether extreme fluctuations signal future major changes. We applied recursive cumulative metaanalysis of randomized controlled trials to evaluate the relative change in the pooled treatment effect (odds ratio) over time for 60 interventions in two medical fields (pregnancy/perinatal medicine, n = 45 interventions; myocardial infarction, n = 15 interventions). We evaluated the scatter of relative changes for different numbers of total patients in previous trials. Outlier cases were noted with changes greater than 2.5 standard deviations of the expected. With 500 accumulated patients, the pooled odds ratio may change by 0.6- to 1.7-fold in the immediate future. When 2000 patients have already been randomized, the respective figures are between 0.74- and 1.35-fold for pregnancy/perinatal medicine and between 0.83- and 1.21-fold for myocardial infarction studies. Extreme early fluctuations in the treatment effect were observed in three interventions (magnesium in myocardial infarction, calcium and antiplatelet agents for prevention of preeclampsia), where recent mega-trials have contradicted prior metaanalyses, as well as in four other examples where early large treatment effects were dissipated when more data appeared. Past experience may help quantify the uncertainty surrounding the treatment effects reported in early clinical trials and their metaanalyses. Early wide oscillations in the evolution of the treatment effect for specific interventions may sometimes signal further major changes in the future.

Evolution of treatment effects over time: Empirical insight from recursive cumulative metaanalyses

Evidence on how much medical interventions work may change over time. It is important to determine what fluctuations in the treatment effect reported by randomized trials and their metaanalyses may be expected and whether extreme fluctuations signal future major changes. We applied recursive cumulative metaanalysis of randomized controlled trials to evaluate the relative change in the pooled treatment effect (odds ratio) over time for 60 interventions in two medical fields (pregnancy/perinatal medicine, n = 45 interventions; myocardial infarction, n = 15 interventions). We evaluated the scatter of relative changes for different numbers of total patients in previous trials. Outlier cases were noted with changes greater than 2.5 standard deviations of the expected. With 500 accumulated patients, the pooled odds ratio may change by 0.6- to 1.7-fold in the immediate future. When 2000 patients have already been randomized, the respective figures are between 0.74- and 1.35-fold for pregnancy/perinatal medicine and between 0.83- and 1.21-fold for myocardial infarction studies. Extreme early fluctuations in the treatment effect were observed in three interventions (magnesium in myocardial infarction, calcium and antiplatelet agents for prevention of preeclampsia), where recent mega-trials have contradicted prior metaanalyses, as well as in four other examples where early large treatment effects were dissipated when more data appeared. Past experience may help quantify the uncertainty surrounding the treatment effects reported in early clinical trials and their metaanalyses. Early wide oscillations in the evolution of the treatment effect for specific interventions may sometimes signal further major changes 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.

Balloon catheter for induction of labor in nulliparous women with prelabor rupture of the membranes at term. A preliminary report

The balloon catheter method has been described as an effective method for cervical ripening hitherto used exclusively before rupture of the membranes. We found it of interest to perform a pilot study of the balloon catheter method after rupture of the membranes. In 18 nulliparous women, with an unripe cervix (Bishop score < or = 5) 48 h after prelabor rupture of the membranes at term, cervical ripening was performed using a 26-gauge balloon catheter. Seventy six percent of these women delivered vaginally. Clinical and neonatal outcome data did not differ as compared with term pregnant women who entered labor spontaneously or had a ripe cervix (Bishop score >5) and labor induced with oxytocin within 48 h after prelabor rupture of the membranes. Despite visualization of a pool of amniotic fluid in the vagina on speculum examination on admission, there was a high proportion of patients with an intact forebag observed during the birth process. This preliminary report indicates that the balloon catheter method might be a well-tolerated, safe, and effective method for induction of labor after rupture of the membranes at term.

Prostaglandin E2 preparations for preinduction cervical ripening

PGE2 is an effective agent for cervical ripening. It is most effective when administered intravaginally. Patients with unfavorable cervices who begin labor during cervical ripening have greater gestational ages, more baseline uterine activity, more initial uterine activity in response to PGE2, and lesser cesarean delivery rate than those patients who do not begin labor during cervical ripening. However, PGE2 should not be continued or administered when the patient is in active labor because it leads to unacceptable rates of hyperstimulation. Unfortunately, cervical ripening with PGE2 has little or no effect on the overall cesarean delivery rate.

Prostaglandins versus oxytocin for prelabour rupture of membranes at or near term

BACKGROUND

The conventional method of induction of labour is with intravenous oxytocin. More recently, induction with prostaglandins, followed by an infusion of oxytocin if necessary, has been used.

OBJECTIVES

The objective of this review was to assess the effects of induction of labour with prostaglandins compared with oxytocin, at or near term.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register.

SELECTION CRITERIA

Randomised and quasi-randomised trials of early stimulation of uterine contractions with prostaglandins (with or without oxytocin) versus with oxytocin alone (not combined with prostaglandins) in women with spontaneous rupture of membranes before labour (34 weeks or more gestation).

DATA COLLECTION AND ANALYSIS

Two reviewers assessed trial quality and extracted data.

MAIN RESULTS

Seventeen trials were included. Most of the trials were of moderate to good quality. Based on six trials, prostaglandins compared with oxytocin were associated with increased chorioamnionitis (odds ratio of 1.49, 95% confidence interval 1.07 to 2.09) and maternal nausea/vomiting. Based on eight trials, prostaglandins were associated with a decrease in epidural analgesia, odds ratio of 0.85, 95% confidence interval 0.73 to 0.98 and internal fetal heart rate monitoring (based on one trial). Caesarean section, endometritis and perinatal mortality were not significantly different between the groups.

REVIEWER'S CONCLUSIONS

Women with prelabour rupture of membranes at or near term having their labour induced with prostaglandins appear to have a lower risk of epidural analgesia and fetal heart rate monitoring. However there appears to be an increased risk of chorioamnionitis and nausea/vomiting with prostaglandins compared to oxytocin.

Prostaglandins versus oxytocin for prelabour rupture of membranes at term

BACKGROUND

The conventional method of induction of labour is with intravenous oxytocin. More recently, induction with prostaglandins, followed by an infusion of oxytocin if necessary, has been used.

OBJECTIVES

The objective of this review was to assess the effects of induction of labour with prostaglandins versus oxytocin for prelabour rupture of membranes at term.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register.

SELECTION CRITERIA

Randomised and quasi-randomised trials of early stimulation of uterine contractions with prostaglandins (with or without oxytocin) versus with oxytocin alone (not combined with prostaglandins) in women with spontaneous rupture of membranes at term (37 weeks or more gestation).

DATA COLLECTION AND ANALYSIS

Two reviewers assessed trial quality and extracted data.

MAIN RESULTS

Eight trials were included. Based on three trials, prostaglandins compared to oxytocin were associated with increased chorioamnionitis (odds ratio of 1.51, 95% confidence interval 1.07 to 2.12) and neonatal infections (odds ratio 1.63, 95% confidence interval 1.00 to 2.66). Based on four trials, prostaglandins were associated with a decrease in epidural analgesia (odds ratio of 0.86, 95% confidence interval 0.73 to 1.00) and internal fetal heart rate monitoring (based on one trial). Caesarean section, endometritis and perinatal mortality were not significantly different between the groups.

REVIEWER'S CONCLUSIONS

Women with prelabour rupture of membranes at term having their labour induced with prostaglandins appear to have a lower risk of epidural analgesia and fetal heart rate monitoring. However there appears to be an increased risk of chorioamnionitis and neonatal infections after prostaglandin induction compared to oxytocin.

Prostaglandins 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. However an expectant approach may be less likely to result in caesarean section.

OBJECTIVES

The objective of this review was to assess the effects of induction of labour with prostaglandins versus expectant management for prelabour rupture of membranes at or near term.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing early use of prostaglandins (with or without oxytocin) with no early use of prostaglandins in women with spontaneous rupture of membranes before labour, and 34 weeks or more of gestation.

DATA COLLECTION AND ANALYSIS

Trials were assessed for quality and data were abstracted.

MAIN RESULTS

Fifteen trials were included. Most were of moderate to good quality. Different forms of prostaglandin preparations were used in these trials and it may be inappropriate to combine their results. Induction of labour by prostaglandins was associated with a decreased risk of chorioamnionitis (odds ratio 0.77, 95% confidence interval 0.61 to 0.97) based on eight trials and admission to neonatal intensive care (odds ratio 0.79, 95% confidence interval 0. 66 to 0.94) based on seven trials. No difference was detected for rate of caesarean section, although induction by prostaglandins was associated with a more frequent maternal diarrhoea and use of anaesthesia and/or analgesia. Based on one trial, women were more likely to view their care positively if labour was induced with prostaglandins,.

REVIEWER'S CONCLUSIONS

Induction of labour with prostaglandins appears to decrease the risk of maternal infection (chorioamnionitis) and admission to neonatal intensive care. Induction of labour with prostaglandins does not appear to increase the rate of caesarean section, although it is associated with more frequent maternal diarrhoea and pain relief.

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.

Induction of labor in patients with term premature rupture of membranes. Effect on perinatal outcome

OBJECTIVE

To determine whether delayed induction of labor in patients with premature rupture of membranes (PROM) at term has beneficial effects on the mother or the infant.

STUDY DESIGN

Retrospective analysis of our database revealed 576 patients >37 weeks of gestation with PROM, who delivered live-born infants without major congenital anomalies. We analyzed the frequencies of primary cesarean, neonatal intensive care unit (NICU) admissions, and oxytocin use by time since hospital admission and interval until onset of labor.

RESULTS

NICU admission increased from 1.9% in <3 h between admission to onset of labor to 13.3% after >18 h. Admission-onset of labor interval, birth weight of <2,500 or >4,000 g and meconium were all more important determinants of NICU admission than gestational age, duration of labor, PROM, and ROM. Prolonged admission-onset of labor interval was associated with an increased risk of variable decelerations (p < 0.001). Primary cesarean rates increased progressively with longer intervals between admission and onset of labor. Stepwise discriminant function analysis revealed that labor duration, admission-onset of labor interval, gestational age, and birth weight of <2,500 g were all more important determinants of primary cesarean delivery than the durations of PROM or ROM.

CONCLUSIONS

The increased frequencies of NICU admission, variable decelerations, and primary cesarean suggest that delayed labor induction after hospital admission was linked to worsened perinatal outcomes. These results may have been influenced by usually performing a single digital examination as part of initial evaluation of term patients who present with PROM. Based on our data, we suggest immediate induction for PROM at term, especially if digital examination has been performed.

Medication use during the perinatal period

OBJECTIVE

To briefly describe the drug therapy administered during the perinatal period of pregnancy for common maternal and fetal complications, and to identify those agents that should not be used for these conditions.

DATA SOURCES

References were obtained from an ongoing literature search of peer-reviewed obstetric and gynecologic journals and other selected medical and pharmacy journals available in the English language. Primary search vehicle was a weekly review of the tables of contents of nearly 1,300 medical journals provided by Reference Update (Institute of Scientific Information, Philadelphia). MEDLINE searches were also conducted using key terms for each subtopic.

STUDY SELECTION

Specific references were selected for each topic based on the adequacy of their study design, patient population, and a recent publication date. Reviews were used if a large number of primary references would have been required to adequately describe the topic.

DATA EXTRACTION

Most references reflected the current opinions expressed in the Educational (Technical) Bulletin and Committee Opinion series published by the American College of Obstetricians and Gynecologists. Recent, well-conducted studies that arrived at different conclusions were also included.

DATA SYNTHESIS

Data obtained from each reference reflected the conclusions of the authors based on their research or an analysis of the research on others on the appropriate use of the drug(s) for the specific condition being treated.

CONCLUSION

Drug therapy during the perinatal period is frequently required and can be beneficial for the mother, fetus, and newborn. Many complications previously associated with severe morbidity and mortality, such as infections, premature rupture of membranes, preterm labor, hypertension, maternal pain during labor, and postpartum hemorrhage, are now controlled with appropriate pharmacologic therapy. All health professionals who provide services to pregnant women should be knowledgeable in this drug therapy.

International multicenter term PROM study: evaluation of predictors of neonatal infection in infants born to patients with premature rupture of membranes at term. Premature Rupture of the Membranes

OBJECTIVE

Our objective was to determine significant predictors for the development of neonatal infection in infants born to patients with premature rupture of membranes at term.

STUDY DESIGN

Multivariate analysis was used to determine the significant predictors of neonatal infection in infants born to women with premature rupture of the membranes who were enrolled in the Term PROM Study. In a randomized, controlled trial, the Term PROM Study recently compared induction of labor with expectant management for premature rupture of membranes at term.

RESULTS

The following variables were identified as independent predictors of neonatal infection: clinical chorioamnionitis (odds ratio 5.89, P < .0001), positive maternal group B streptococcal status (vs negative or unknown, odds ratio 3.08, P < .0001), 7 to 8 vaginal digital examinations (vs 0 to 2, odds ratio 2.37, P = .04), 24 to < 48 hours from membrane rupture to active labor (vs < 12 hours, odds ratio 1.97, P = .02), > or = 48 hours from membrane rupture to active labor (vs < 12 hours, odds ratio 2.25, P = .01), and maternal antibiotics before delivery (odds ratio 1.63, P = .05).

CONCLUSIONS

Among infants born to patients with premature rupture of membranes at term, clinical chorioamnionitis and maternal colonization with group B streptococci are the most important predictors of subsequent neonatal infection.

Pathophysiology, diagnosis, and management of intraamniotic infection

Intraamniotic infection (IAI) is a term used to describe a clinically diagnosed infection of the contents of the uterus. It is found most often after rupture of the membranes. The most useful diagnostic tests are physical examination, amniotic fluid glucose determination, and amniotic fluid Gram's stain. There is no clearly established means for the prevention of IAI, but cervical examinations and cervical manipulation can increase the risk, so caution with their use is still warranted. Treatment for this infection should be initiated when the diagnosis is made to provide the lowest risk of neonatal and maternal complications. Ampicillin or penicillin plus gentamicin are the most extensively tested antibiotics for treatment before delivery. Clindamycin or metronidazole should be added if a cesarean section is performed. As a general rule, antibiotics should be continued postpartum until the patient has been afebrile and asymptomatic for a minimum of 24 hours. Neonatal complications of IAI may be substantial especially for the premature fetus. Women with this infection have a greater risk for dysfunctional labor and cesarean section.

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.

Birth centre practices in Australia

The aim of this study was to review birth centre practices in Australia. Questionnaires were completed from 22 of 24 centres. Great variations were observed between the centres in clinical practices like number of routine antenatal visits, pattern of medical review, and transfer rates. Definition of low-risk as expressed by booking and transfer criteria also showed great variations, and generally these criteria became more liberal with experience. From 1991 to 1995 there was an average increase of approximately 1,000 bookings per year in the 22 centres taken together. The average transfer rate over the whole period was 22% antepartum and 18% intrapartum. The transfer rates increased slightly over the 5-year period, by 4.8% during pregnancy and 2.5% intrapartum. A majority was optimistic about the future, and estimated that the potential market for birth centres was around 16% compared with the present figure of less than 5%. A general view was that women were not well informed about the birth-centre option.

Women's evaluations of induction of labor versus expectant management for prelabor rupture of the membranes at term. TermPROM Study Group

BACKGROUND

Induction of labor has become common practice in many Western countries, but few studies have assessed women's views.

METHODS

A randomized, controlled trial was conducted at 72 hospitals in six countries. Five thousand forty-one women meeting eligibility criteria, with no contraindications for induction of labor or expectant management, were randomly assigned to four groups: induction with intravenous oxytocin, induction with vaginal prostaglandin E2 gel, or expectant management followed by induction with either oxytocin or with prostaglandin E2 gel if complications developed. The three main outcome measures were evaluations of the treatment received, perceived control during childbirth, and evaluations of the experience of trial participation.

RESULTS

Questionnaires were completed by 81.9 percent of the sample. No significant differences occurred between the two induction groups. Compared with the expectant management groups, induced women were less likely to report there was nothing they liked about their treatment and less likely to report that the treatment caused additional worry. No between-group differences occurred in experienced control during childbirth. Women in the induction groups were more likely to be willing to participate in the study again and to feel reassured.

CONCLUSIONS

Women's preferences should be considered when making decisions about their method of management when membranes rupture before labor. Obtaining participants' views is both feasible and worthwhile when evaluating forms of medical care.

International Multicentre Term Prelabor Rupture of Membranes Study: evaluation of predictors of clinical chorioamnionitis and postpartum fever in patients with prelabor rupture of membranes at term

OBJECTIVES

Our purpose was to determine significant predictors for the development of clinical chorioamnionitis and postpartum fever in patients with prelabor rupture of membranes at term.

STUDY DESIGN

Logistic regression analysis with odds ratios and 95% confidence intervals was used to determine the significant predictors of clinical chorioamnionitis and postpartum fever in women with prelabor rupture of membranes at term enrolled in this study. The study recently compared in a randomized controlled trial four strategies of management: induction with oxytocin, induction with prostaglandin, expectant management, and, if failed, induction with oxytocin or prostaglandin.

RESULTS

The following variables were significantly associated with clinical chorioamnionitis: (1) number of digital vaginal examinations: > 8, 7 to 8, 5 to 6, 3 to 4 (vs 0 to 2) (odds ratio 5.07, 3.80, 2.62, 2.06); (2) duration of active labor: > or = 12, 9 to < 12, 6 to < 9 hours (vs < 3 hours) (odds ratio 4.12, 2.94, 1.97); (3) meconium-stained amniotic fluid (odds ratio 2.28); (4) parity of 0 (odds ratio 1.80); (5) time from membrane rupture to active labor: > or = 48, 24 to < 48 hours (vs < 12 hours) (odds ratio 1.76, 1.77); and (6) group B streptococcal colonization (odds ratio 1.71). Variables significantly associated with postpartum fever were (1) clinical chorioamnionitis (odds ratio 5.37), (2) duration of active labor: > or = 12, 9 to < 12, 6 to < 9, 2 to < 6 hours (vs < 3 hours) (odds ratio 4.86, 3.53, 3.46, 3.04), (3) cesarean section, operative vaginal delivery (odds ratio 3.97, 1.86), (4) group B streptococcal colonization (odds ratio 1.88), and (5) maternal antibiotics before delivery (odds ratio 1.94).

CONCLUSIONS

Increasing numbers of digital vaginal examinations, longer duration of active labor, and meconium staining of the amniotic fluid were the most important risk factors for the development of clinical chorioamnionitis in women with prelabor rupture of membranes at term. The most important risk factors for the development of postpartum fever were clinical chorioamnionitis, increasing duration of active labor, and cesarean section delivery.

Maternal colonization with group B Streptococcus and prelabor rupture of membranes at term: the role of induction of labor. TermPROM Study Group

OBJECTIVES

Our purpose was to determine the effect of induction of labor on neonatal infection if mothers are group B streptococci positive and have prelabor rupture of membranes at term.

STUDY DESIGN

In the TermPROM study 5041 women were randomized to induction with intravenous oxytocin, induction with vaginal prostaglandin E2 gel, or expectant management with induction, if needed. Of these, 4834 women had vaginal or introital swabs for group B streptococci taken at entry. We used logistic regression to test for effects of treatment within group B streptococci subgroups.

RESULTS

Group B streptococci were predictive of neonatal infection for the induction with vaginal prostaglandin E2 gel and expectant groups but not for the induction with oxytocin group. For women positive for group B streptococci the rates of neonatal infection were 2.5% for the induction with oxytocin group and > 8% for all other groups.

CONCLUSIONS

Induction of labor with intravenous oxytocin may be preferable for group B streptococci-positive women with prelabor rupture of membranes at term.

Evaluating the benefits of a patient information video during the informed consent process

The study objective was to evaluate the effect of a patient information video during the informed consent process of a perinatal trial. Ninety women, between 19 and 33 weeks gestation, were randomised to receive written information about this perinatal trial and watch an information video or to receive written information only. Participants completed a questionnaire immediately after entry and 2-4 weeks later assessing knowledge of; feelings about the worth of; and willingness for future participation in the perinatal trial. When initially asked, more women who watched the video thought they would consent to the study (chi 2 = 6.3; df = 1; P = 0.01). No differences in knowledge about the perinatal trial were found initially, but 2-4 weeks later more knowledge had been retained by women who had watched the video (chi 2 = 6.7; df = 1; P = 0.01). These results suggest that a patient information video combined with an information sheet may result in greater participation in a research trial and may increase women's knowledge of a specific health problem and related research trial.

Rupture of the membranes and postpartum infection

The greatest risk of preterm prelabour rupture of membranes (PPROM) is preterm delivery. According to the Perinatal Information System of Slovenia there were 5.92% preterm deliveries in 1994. We studied 809 deliveries of less than 34 weeks of gestation in the Ljubljana Maternity, from 1992 to 1994; 33.7% of these started with PPROM. Risk factors for PPROM were conization, cerclage and use of antibiotics for any reason in current pregnancy. Amnionitis and febrile illness during labour increased with longer duration of PPROM but maternal postpartum infections did not. In neonates, more cases of lower Apgar scores after 1 and 5 min and more cases of suspected sepsis were found with the increased duration of PPROM. In Slovenia, with good facilities for transport in utero and good neonatal care, after PPROM it is best to transport the pregnant women to the third level center and then wait until labour starts or to recur to prompt delivery when maternal or fetal signs so require. From 1987 to 1993 there were 159264 deliveries in gestations equal to or over 34 weeks; 20.8% started with PROM. In our observational study we found the best results when labour was induced. There are, however, many disagreements about the management of (P)PROM.

Premature rupture of the membranes: neonatal consequences

Premature rupture of the membranes (PROM), membrane rupture before the onset of labor, occurs in 2% to 18% of pregnancies. The time from PROM to delivery (latency) is usually less than 48 hours in term pregnancy. Therefore, the risks of PROM at term are related to fetal distress, prolapsed cord, abruptio placenta, and rarely, infection. Preterm PROM (pPROM), PROM before 37 weeks' gestation, accounts for 20% to 40% of PROM, and the incidence is doubled in multiple gestations. The latency period in pPROM is inversely related to the gestational age thereby increasing the risks of oligohydramnios and infection in very premature infants and their mothers. Because pPROM is associated with 30% to 40% of premature births, pPROM is also responsible for the neonatal problems resulting from prematurity. This review examines the impact of PROM on the neonate including fetal distress, prematurity, infection, pulmonary hypoplasia, and restriction deformations.

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.