Prevention of Post-Partum Hemorrhage: Comparison of Oxytocin and Misoprostol. A Two center study in the Bamenda and Nkwen Health Districts

Abstract

Background: Postpartum hemorrhage is one of the most common obstetrical complications affecting up to 18% of deliveries. Globally, it is responsible for 35 – 55% of peripartum maternal deaths. In Cameroon, the maternal mortality rate is at 406 maternal death per 100,000 live births, with PPH being the leading cause accounting for about 25%. This study aimed to compare the efficacy and safety of misoprostol versus oxytocin in the prevention of postpartum hemorrhage in the Bamenda Health District and Nkwen Health District. Methods: This was a hospital-based randomized clinical trial study in the Bamenda Regional Hospital and Nkwen District Hospital. The study was conducted from March 1st to May 31st 2021 including pregnant women who delivered at the maternity at these two hospitals. All their pregnancy was singleton gestation at term and haven given their informed consent. Women with known history of cardiac, renal, hepatic diseases or any coagulopathy, Cesarean delivery were excluded. We randomized 308 participants in a 1:1 ratio to receive 800 μg of oral misoprostol or 10IU of oxytocin intramuscularly during the active management of third stage of labor (AMSTL). The Hemoglobin (Hb) concentration and hematocrit (HCT) of the participants were measured before and 24hrs after delivery. Our primary outcome of interest was (Post-Partum Hemorrhage) PPH, defined as Hb change ≥ 1g/dl within 24hrs of delivery. Secondary outcomes included; mean Hb change, Hb change ≥2g/dl (severe PPH). Dichotomous outcomes between study groups were compared by estimating crude relative risks (RRs) with 95% confidence intervals. Logistic regression (the chi-square test) was done to determine the factors associated with the occurrence of postpartum hemorrhage, with a level of significance at 5%. Results: After 24hrs, Postpartum hemorrhage (PPH) occurred in 41 (26.6%) and 47 (30.5%) participants in the misoprostol and oxytocin groups respectively (RR= 0.87, 95% C.I= 0.61 - 1.24, p=0.449). Severe postpartum hemorrhage occurred in 3 (1.9%) and 5 (3.2%) participants in the misoprostol and oxytocin groups respectively (RR= 0.6, 95% C.I=0.15 - 2.47, p=0.723). Past history of PPH (aOR=10.1 (3.5 – 28.6), p<0.0001), augmentation of labor (aOR=3.4 (1.6 – 7.1), p=0.0011), fetal birth weight ≥3.5Kg (aOR=2.5 (1.3 – 4.8), p=0.0074) and retained products (aOR= 8.4 (4.2 – 16.7), p<0.0001) were risk factors of PPH. Participants in the misoprostol group more commonly experienced shivering (RR 3.2, 95% CI 2.0 - 5.1, p<0.0001) and nausea/vomiting (RR 35.5, 95% CI 8.9 – 142.2, p<0.0001). Conclusion: Oral misoprostol at the dose of 800μg is as effective as 10 IU IM Oxytocin in the prevention of PPH and is a potent alternative to oxytocin. Most common risk factors of PPH are past history of PPH, augmentation of labor, fetal weight ≥ 3.5kg and retained products. Side effects were mostly associated with 800μg of oral Misoprostol.