Outcome of induction of labour in relation to pre-induction bishop scope

Thesis Report.

ABSTRACT: This study was conducted at maternity hospital, Kathmandu in the year 1998/1999. Objective ; The overall objective of this study was to study the relationship of pre-induction Bishop score(BS) with the outcome of Induction of Labour (IOL). Methodology: A total of 103 patients undergoing IOL was included in the study following informed consent. The study groups were of parity 4 or less, with confirmed gestational age of 28 weeks of more and alive singleton pregnancy with cephalic presentation. Women with PROM and CS were not included. These patients were catagorized by BS at the beginning of induction for comparison of success of IOL, mode of delivery, induction delivery interval(IDI), maternal complications and fetal outcome. Women undergoing induction with low BS of 0-4 (n=48) were grouped in one and those with high BS of 5-8(N=55) into another. Oxytocin infusion without prior cervical ripening was given to all the subjects according to the hospital protocol. Amniotomy was done in the active labour. For the purpose of the study, failed induction was defined as inability to enter in to the active phase of labour despite oxytocin stimulation for a total of 12hrs. Statistical analysis of categoric variables was done using the x2 test and comparison of continuous variables was done with the student t test . A two- tailed p value<0.05 was considered to indicate a significant difference. Results: The indications for IOL did not differ among the two Bishop categories. The rate of IOL was 3.7%. The overall failure of IOL was 25% and failure was significantly higher in the low BS group(43.7%Vs 9.0%).The mean IDI was greater in women who had low BS with high BS(11.16 hrs Vs 9.02 hrs). Caesarean delivery occured more frequently in the low BS group than inthe high BS group (23%Vs 14.5%). Nulliparas in both the study groups had higher Cs rate as cmpared to multiparas. Some had maternal complications which were not significantly different between the groups except for PPH which was higher in low BS group(11% Vs 0%). There was no stillbirth and early neonatal death. The low Apgar score (0-3) at 1 min was found in 3.7% and 4.0% in the low BS and in the high BS group respectively. Similarly, an Apgar score of 4-6 at 1 min. was found in 44.4% and 30.0% in the low BS in the high BS groups respectively. The rest had good Apgar score (7-10). Among the babies , 30% in the low BS group required baby unit admission as compared to 20% in the high BS group. The difference between both the groups were not significant statistically. Conclusion: In the present study, the women with a low BS had higher failure of IOL, higher Cs rate, longer induction delivery interval, higher maternal complications (PPH) and higher baby unit admission rate.

Eng.