RESUMO
OBJECTIVES: To evaluate the efficacy and safety of double balloon catheter for induction of labour in Chinese women with one previous caesarean section and unfavourable cervix at term. DESIGN: Retrospective cohort study. SETTING: A regional hospital in Hong Kong. PATIENTS: Women with previous caesarean delivery requiring induction of labour at term and with an unfavourable cervix from May 2013 to April 2014. MAJOR OUTCOME MEASURES: Primary outcome was to assess rate of successful vaginal delivery (spontaneous or instrument-assisted) using double balloon catheter. Secondary outcomes were double balloon catheter induction-to-delivery and removal-to-delivery interval; cervical score improvement; oxytocin augmentation; maternal or fetal complications during cervical ripening, intrapartum and postpartum period; and risk factors associated with unsuccessful induction. RESULTS: All 24 Chinese women tolerated double balloon catheter well. After double balloon catheter expulsion or removal, the cervix successfully ripened in 18 (75%) cases. The improvement in Bishop score 3 (interquartile range, 2-4) was statistically significant (P<0.001). Overall, 18 (75%) cases were delivered vaginally. The median insertion-to-delivery and removal-to-delivery intervals were 19 (interquartile range, 13.4-23.0) hours and 6.9 (interquartile range, 4.1-10.8) hours, respectively. Compared with cases without, the interval to delivery was statistically significantly shorter in those with spontaneous balloon expulsion or spontaneous membrane rupture during ripening (7.8 vs 3.0 hours; P=0.025). There were no major maternal or neonatal complications. The only factor significantly associated with failed vaginal birth after caesarean was previous caesarean section for failure to progress (P<0.001). CONCLUSIONS: This is the first study using double balloon catheter for induction of labour in Asian Chinese women with previous caesarean section. Using double balloon catheter, we achieved a vaginal birth after caesarean rate of 75% without major complications.
