A retrospective review of pregnancy outcome after misoprostol (prostaglandin E1) induction of labour

ABSTRACT

This retrospective study looked at the outcome of using 50-100 micrograms misoprostol once daily to induce labour compared to the outcome of the overall patient population delivered during the same period (1994-1996). During that period 11,255 patients were delivered and 1037 (9.2) were induced with misoprostol. Results showed a significantly lower mean Caesarean section rate 9.3 for the misoprostol group versus 13.3 for the overall population (p = 0.002, Odds Ratio (OR) 0.67, 95 CI 0.53, 0.83). The abruption rates were not significantly different 0.8 for misoprostol versus 0.4 (p = 0.09, OR 1.86, 95 CI 0.81, 4.09). There was more postpartum haemorrhage in the misoprostol group 5.6 versus 3.5 (p = 0.0006, OR 1.63, 95 CI 1.22, 2.19); a higher incidence of Apgar scores less than 6 at one minute 10.2 versus 7.9 (p = 0.0093, OR 1.33, CI 1.06, 1.65) but not at five minutes 2.9 versus 2.4 (p = 0.674, OR 1.09, CI 0.73, 1.61) and a higher perinatal mortality rate 55/1000 versus 16.3/1000 (p = 0.00, OR 3.5, 95 CI 2.55, 4.80). The rate remained higher but not significantly so when a correction was made to eliminate the high number of intrauterine deaths induced with misoprostol 18/1000 versus 16.3/1000 (p = 0.69, OR 1.11, 95 CI 0.66, 1.84). There were no cases of uterine rupture in either group. In conclusion, there was a significantly lower Caesarean section rate among patients who had once daily misoprostol induction of labour. Close monitoring of the foetus, in patients with misoprostol induction, is needed to detect foetal distress and prophylaxis against postpartum haemorrhage is still mandatory.