Outcomes of pharmacological induction of labour at or near term at Kenyatta National Hospital

Abstract

Background: Induction of labour is artificial initiation of uterine contractions after the period of viability, with the intention of accomplishing delivery prior to onset of spontaneous labor. It is performed when the benefits of expeditious delivery to either mother or uterus outweigh the risk of continuing the pregnancy. The frequency of induction has been increasing, and while it is a beneficial procedure, it is not without risks.

At Kenyatta National Hospital (KNH) currently prostaglandin E2, prostaglandin E I and oxytocin are used for pharmacological labour induction of viable pregnancies at or near term. There have been no recent studies in our setup to evaluate risks and fetal and maternal outcomes following pharmacological induction of labour.

Objective: To describe maternal and fetal outcomes associated with labour induction at or near tenn at Kenyatta National Hospital.

Study design: This was a cross-sectional descriptive study

Study Setting: The setting was in labor ward and post-natal wards, Kenyatta National Hospital.

Sample: 262 pregnant women at gestation age of 2:34 completed weeks, with a live fetus, scheduled for pharmacological induction of labor, during the study period.

Methods: Mothers undergoing induction of labour during the study period were recruited into the study consecutively. A questionnaire was used to obtain data about socio-demographics, obstetric characteristics, methods used for induction, duration of the procedure, and maternal and fetal outcomes.

Results: Most of the participants (64.9010) were aged between 20 to 29 years, 85.'JOA, were married and half of the participants bad attained at least secondary level of education. Majority of the women were primigravidas (58%), and the mean gestational age was 39.9 weeks. The pharmacological methods used for induction of labour included oxytocin infusion alone (1tselo), prostaglandin (either misoprostol or dinoprostone) alone (38.5% and 4.ZOIo respectively) or in combination with artificial rupture of membranes and oxytocin infusion.

The commonest indication for induction was post-datism (50J~%) followed by hypertensive disease (16%). The average duration from induction to delivery was 19.1 hours. The success rate of induction among study participants was 74%. The commonest indication for caesarian section was a diagnosis of failed induction of labour (51.5%) which was defined as failure to achieve vaginal delivery within 24 hours of initiating induction. Most women (94.']010) delivered without any other side effects or complications, while genital tract tears was the most common complication (2.']010). Meconium staining of liquor was noted in 9.9% of cases, and 3.4% had fetal heart rate abnonnality intrapartum. Majority (94.6%) of newborns had an Apgar score Of seven and above. 18 (6.9010) of newborns were admitted to the newborn unit with the commonest diagnosis (66.7%) being birth asphyxia There were two cases of fresh stillborn fetuses.

Conclusions: Pharmacological induction of labour resulted in high rate of success, with good maternal and neonatal outcome. However, the induction to delivery time is prolonged, with many patients taking up to 24 hours, which may pose risks to both the mother and fetus. Patients with a diagnosis ofpost-datism are the majority who undergo the procedure of induction of labour.

Recomendations: Although this study suggests that misoprostol is effective, well designed trials should be conducted to compare the safety and effectiveness of vaginal misoprostoI with dinoprostone and oxytocin in our setting such as routine sweeping of membranes at tenn should be considered in order to reduce the incidence of prolonged pregnancy. There is also need to review protocols concerning the logistics of antenatal and labour drug administration during the procedure because transfer of patients to and from wards for review may be the reason for delays and prolonging of the induction process.