Significance of cervical ripening in pre-induction treatment for premature rupture of membranes at term

A nationwide study of obstetric management and outcomes in premature rupture of membrane at term: Report from the Perinatology Committee, Japan Society of Obstetrics and Gynecology, 2017-2018

AIM

This nationwide study aimed to investigate the practical management of term premature rupture of membrane (PROM) and its relationship with maternal and neonatal outcomes.

METHODS

We conducted a questionnaire survey of 415 facilities participating in the Japan Perinatal Registry Network of the Japan Society of Obstetrics and Gynecology in 2016. The patients were women expecting vaginal birth after PROM at term without clinical chorioamnionitis. We classified the facilities into three groups based on duration of the expectant management after PROM (within 24, 24, and 48 h). Furthermore, we analyzed the association between perinatal outcomes and management protocol using the Japan Perinatal Registry Network Database 2016.

RESULTS

Of 415 facilities, 346 (83.4%) completed and returned the survey. Among 231 facilities with management protocols, an interval of 3 days from PROM to delivery was acceptable in 167 facilities (72.3%). One hundred forty-nine facilities (64.5%) responded that they did not perform mechanical cervical dilation, and 90 (39.0%) used oxytocin as a uterotonic irrespective of cervical maturation. The number of hospitals that had a policy to administer antibiotics to Group B streptococcus-positive patients was 211 (91.3%). Neonatal outcomes at birth and the frequency of cesarean section and postpartum fever did not differ among the three groups.

CONCLUSIONS

Most facilities in the Japan Perinatal Registry Network managed women at term to delivery within 3 days after PROM with attention to bacterial infection. Expectant management up to 48 h after PROM did not increase the risk of postpartum fever, compared to labor induction immediately after PROM.

[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).