RESUMEN
OBJECTIVES: To assess the differences in the maternal and fetal outcomes between pharmacological induced and sponta-neous labour in nulliparous women. MATERIAL AND METHODS: Observational cohort study carried out over a period of 2 years. INCLUSION CRITERIA: nulliparous sin-gleton pregnancies, with cephalic fetal presentation, elective labour induction with intra-vaginal prostaglandin E2 (PGE2) gel (Prepidil® 2 mg) at a gestational age of 41 weeks. CONTROL GROUP: patients who entered labour spontaneously at a gestational age of ≥ 40 weeks. The main demographic maternal characteristics and intra- and postpartum data were extracted from computer records and obstetrics diaries and were used for the analysis. RESULTS: One hundred and three patients with induction of labour and 97 with spontaneous labour were enrolled. Cesarean delivery was performed in 18 cases (17.5%), all in the induction group. There were no differences in newborn weights between the 2 groups while both the 1-minute and 5-minute Apgar scores were significantly higher in the spontaneous group (p = 0.014 and p = 0.0003, respectively). Women in the induction group had a significantly longer duration of I stage labour in comparison with spontaneous group (p < 0.0001). CONCLUSIONS: Primiparous women whose labour was induced spent a longer time in labour than women who presented in spontaneous labour. Clinicians should keep in mind that a slow rate of dilation in a woman being induced may be normal. For this reason, an arrest diagnosis needs to be carefully considered.