Maternal intravaginal prostaglandin E2 gel before elective caesarean section at term to induce catecholamine surge in cord blood: randomised, placebo controlled study

Is Exposure to Intrapartum Prostaglandins for Labor Induction Associated with a Lower Incidence of Neonatal Respiratory Distress Syndrome?

OBJECTIVE

Respiratory distress syndrome (RDS) is implicated in 30% of neonatal deaths. Since prostaglandins promote surfactant secretion and labor is associated with a lower risk of RDS in term neonates, it is plausible that synthetic prostaglandin (sPG) exposure is associated with a lower risk of RDS. Thus, we evaluated the association between sPG exposure and RDS in neonates born after the induction of labor (IOL).

STUDY DESIGN

Secondary analysis of women with singleton pregnancies undergoing IOL at 34^0/7 to 42^0/7 weeks in the nuMoM2b study, a multicenter prospective cohort of nulliparous women. RDS rates and secondary neonatal outcomes in neonates with intrapartum sPG exposure were compared with those who had IOL with non-sPG methods (e.g., balloon catheter, amniotomy, oxytocin, and laminaria). Logistic regression models estimated the association of sPG with RDS and with secondary outcomes after adjustment for clinical and demographic factors (including gestational age). A sensitivity analysis was performed in which analysis was restricted to those with an admission cervical dilation ≤2 cm.

RESULTS

Of 10,038 women in the total cohort, 3,071 met inclusion criteria; 1,444 were exposed and 1,627 were unexposed to sPGs. Antenatal corticosteroid exposure rates were low (3.0%) and similar between groups. In univariable analysis, neonates with sPG exposure had higher rates of RDS (3.2 vs. 2.0%, odds ratio [OR]: 1.59, 95% confidence interval [CI]: 1.01-2.50). This relationship was similar by gestational age at delivery (term vs. preterm, interaction p = 0.14). After adjustment, the association between sPG and RDS was no longer significant (adjusted odds ratio: 1.4, 95% CI: 0.9-2.3). When analysis was restricted to subjects with admission cervical dilation of ≤2 cm, there was also no association between sPG exposure and RDS.

CONCLUSION

In pregnancies between 34 and 42 weeks of gestation, exposure to sPG for cervical ripening or labor induction was not associated with newborn RDS.

KEY POINTS

· RDS is implicated in 30% of neonatal deaths.. · sPG exposure was not associated with RDS.. · Avoiding preterm birth remains crucial in RDS prevention..

Rectal vs. sublingual misoprostol before cesarean section: double-blind, three-arm, randomized clinical trial

PURPOSE

The commonest surgical procedure for women is cesarean delivery. Postpartum hemorrhage and intra-operative blood during cesarean delivery is a major concern to all obstetricians. This study was conducted to assess the efficacy of the adjuvant use of misoprostol and oxytocin in decreasing intra-operative blood loss in cesarean delivery.

METHODS

This was a double-blinded randomized clinical trial including 636 term pregnant woman scheduled for cesarean section at Ain Shams University Maternity Hospital, Cairo, Egypt, between February 2013 and February 2014. Participants received either 400-μg misoprostol rectally or sublingually or placebo before cesarean section together with 5-IU oxytocin IV. The main outcome measure was intra-operative blood loss. Difference between the three groups was analyzed using one-way ANOVA test (for numeric variables) and Chi-square test (for categorical variables). P < 0.05 was considered statistically significant.

RESULTS

Intra-operative blood loss was higher in patients who did not receive misoprostol (Placebo Group) (295-1075 ml, 641.7 ± 135.7) than those who received it, regardless the route of administration, rectal (135-830 ml, 457.5 ± 140.7; P < 0.001), and sublingual (135-680 ml, 357.8 ± 129.7; P < 0.001). In addition, sublingual route was associated with significantly lower estimated intra-operative blood loss compared to rectal administration (P < 0.001).

CONCLUSIONS

Misoprostol with oxytocin is an effective drug-combination for decreasing intra-operative blood loss during cesarian section with clinical superiority to sublingual over rectal route.

Prostaglandins before caesarean section for preventing neonatal respiratory distress

BACKGROUND

Respiratory distress (RD) can occur in both preterm and term neonates born through normal vaginal delivery or caesarean section (CS). It accounts for about 30% of neonatal deaths and can occur at any time following birth. Respiratory distress syndrome (RDS), transient tachypnoea (rapid breathing) of the newborn and persistent pulmonary hypertension (increased blood pressure of pulmonary vessels) of the newborn are the most frequent clinical presentations of neonatal RD. Prostaglandins are used in routine obstetric practice to ripen the uterine cervix and to trigger labour, with those of the E series being preferred over others due to the fact that they are more uteroselective. Administration of prostaglandins to an expectant mother before delivery causes reabsorption of lung fluid from the fetal lung and promotes surfactant secretion by inducing a catecholamine surge. As a result, significant reduction in neonatal respiratory morbidity following a CS could be obtained, leading to reduced long-term complications such as bronchopulmonary dysplasia (chronic lung disease with lung tissue modification) and asthma.

OBJECTIVES

The objective of this review was to determine if administration of prostaglandins before CS can improve respiratory outcomes of newborns.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 September 2013). We also searched three clinical trial registries; ClinicalTrials.gov, the Australian New Zealand Clinical Trials Registry and the WHO Clinical Trials Registry Platform (ICTRP), for ongoing studies (24 June 2013).

SELECTION CRITERIA

We included all published and unpublished randomised controlled trials comparing the use of prostaglandins with other treatments (including placebo) to reduce neonatal respiratory morbidity. Participants were pregnant women with an indication for a CS, and we compared administration of prostaglandins prior to CS with no treatment, placebo or another treatment.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion and assessed trial quality, with the third review author referred to for settling any disagreements. Two review authors extracted data. Data were checked for accuracy. We used the Cochrane tool for assessing risk of bias in the included study and contacted the study authors to request additional information where appropriate.

MAIN RESULTS

We found one randomised controlled trial with a low risk of bias which was carried out in a tertiary neonatal care centre in Australia. The study involved 36 women (18 received intravaginal prostaglandin E 2 gel and 18 received placebo).There was one case of neonatal respiratory distress in the control group, which the trialist reported as transient tachypnoea of the newborn (risk ratio (RR) 0.33, 95% confidence interval (CI) 0.01 to 7.68, one study, n = 36).None of the neonates required mechanical ventilation and the trial authors reported median Apgar scores at one and five minutes as being similar in both groups.There were no treatment-related side effects in either group. Noradrenaline concentrations (median values (range)) were reported as being significantly higher in the cord blood samples of the intervention group compared to the control group.

AUTHORS' CONCLUSIONS

Although the trial authors reported a significant increase in catecholamine levels in the intervention group, there was no significant difference in the respiratory outcomes between intervention and control groups. The quality of evidence was graded as low because the sample size was small and there were few events. No definite conclusions can thus be drawn on the effects of prostaglandins on neonatal respiratory outcomes from this review.