International Journal of Clinical Obstetrics and Gynaecology

Background: Induction of labour is one of the common interventions practiced in modern obstetrics. Overall, throughout the world, up to 20 percent of women have labour induced by one method or the other. Induction is indicated before the spontaneous onset of labour when the benefit to the mother or fetus is perceived to outweigh continuation of pregnancy.

Vaginal pH may be one such factor that may influence the efficacy of prostaglandins for cervical ripening /labour induction. Vaginal pH may alter PGE2 release from the delivery vehicle, alter PGE2 absorption or metabolism and modulate prostaglandin activity in the cervico vaginal environment, thus altering its clinical efficacy.

Aims & Objectives: To compare the efficacy of Dinoprostone gel for labour induction in patients with vaginal pH < 4.5 and pH >4.5.

2. To improve the patient selection for PGE2 gel induction which would reduce the incidence of failed induction and unwanted outcomes.

Materials Methods: After obtaining clearance from the hospital ethical committee, this cohort study was undertaken in the Department of Obstetrics and Gynaecology at Government Kilpauk Medical College and Hospital, Chennai from October 2017 to March 2018. Written informed consent was obtained from the women explaining it to them in their language they best understand. This hospital based study included 54 antenatal women attending labour ward of Kilpauk Medical College and Hospital, Chennai.

Inclusion Criteria: Singleton pregnancy with vertex presentation, unfavourable cervix and no contraindication to vaginal delivery with reactive NST.

•Hypersensitivity to prostaglandins

•Premature rupture of membranes

•Placenta previa

•Previous cesarean delivery or a history of uterine surgery

•Major cephalo pelvic disproportion.

The sample size should be minimum of 27 for each group and so total sample size is 54.

Results: A total of 54 cases with unfavourable cervix were enrolled in this study. They were divided into 2 groups based on the vaginal pH. Out of 54 there were 27 cases in group 1 (vaginal pH <4.5) and 27 cases in group 2 (vaginal pH>4.5).

Conclusion: This shows that vaginal pH has significant effect on cervical ripening and Bishop score change and may lead to improved clinical efficacy of Dinoprostone gel. So, we can see that assessing vaginal pH before induction can be an useful parameter in predicting the outcome of labour in pregnant women who are undergoing labour induction with PGE2 gel.