Factors and outcomes associated with the induction of labour in Latin America

OBJECTIVE: To describe the prevalence of labour induction, together with its risk factors and outcomes in Latin America. DESIGN: Analysis of the 2005 WHO global survey database. SETTING: Eight selected Latin American countries. POPULATION: All women who gave birth during the study period in 120 participating institutions. METHODS: Bivariate and multivariate analyses. MAIN OUTCOME MEASURES: Indications for labour induction per country, success rate per method, risk factors for induction, and maternal and perinatal outcomes. RESULTS: Of the 97,095 deliveries included in the survey, 11,077 (11.4%) were induced, with 74.2% occurring in public institutions, 20.9% in social security hospitals and 4.9% in private institutions. Induction rates ranged from 5.1% in Peru to 20.1% in Cuba. The main indications were premature rupture of membranes (25.3%) and elective induction (28.9%). The success rate of vaginal delivery was very similar for oxytocin (69.9%) and misoprostol (74.8%), with an overall success rate of 70.4%. Induced labour was more common in women over 35 years of age. Maternal complications included higher rates of perineal laceration, need for uterotonic agents, hysterectomy, ICU admission, hospital stay>7 days and increased need for anaesthetic/analgesic procedures. Some adverse perinatal outcomes were also higher: low 5-minute Apgar score, very low birthweight, admission to neonatal ICU and delayed initiation of breastfeeding. CONCLUSIONS: In Latin America, labour was induced in slightly more than 10% of deliveries; success rates were high irrespective of the method used. Induced labour is, however, associated with poorer maternal and perinatal outcomes than spontaneous labour.