An Analysis of the NSW Midwives Data Collection over an 11-Year Period to Determine the Risks to the Mother and the Neonate of Induced Delivery for Non-Obstetric Indication at Term
Objective. To determine the risks of induced term delivery to the mother and neonate at different gestational ages in the absence of obstetric indications. Study Design. All deliveries in New South Wales (NSW) between 1998 and 2008 were reviewed from the MDC. Uncomplicated pregnancies which were induced for non-obstetric reasons after 37 completed weeks were reviewed. This was a retrospective, historical cohort study, and both maternal and neonatal outcomes were analysed and compared between different gestational age groups. Results. An analysis of the data shows that induction of labour after 37 completed weeks exposes the fetus and mother to different levels of risk at different gestations. Conclusion. In an uncomplicated pregnancy, induction of labour is associated with the highest rate of neonatal complication at 37 weeks as compared with rates at later gestations. With each ensuing week, the neonatal outcome improves. At 40 weeks the likelihood of neonatal intensive care admission, low Apgar scores, and perinatal death rate is at its lowest, and then there is a slight but not significant rise after 41 weeks. The likelihood of caesarean section is the lowest when inductions are carried out at 39 weeks and is the highest at 41 weeks and over. 1. Introduction Induction of labour is defined as the artificial initiation of uterine contractions leading to dilatation of the cervix at or after 24 weeks [1]. Induction of labour is relatively safe; hence both clinicians and women feel that this management option normally does not pose serious risk for the mother and the neonate [2]. As a consequence, the rate of this intervention is rising [1, 3]. Induction of labour without a medical indication is termed elective induction. A recent systematic review concludes that elective induction appears to be increasing even more rapidly than inductions, which are indicated on obstetric grounds [4]. Inductions based on well-established clinical guidelines are associated with improved maternal and neonatal health outcomes. On the other hand, a number of maternal and neonatal complications, particularly caesarean delivery, have been observed among women induced without a standard clinical indication [2, 5]. A pregnant woman is at “term” when her pregnancy duration reaches 37 completed weeks [6]. New South Wales Health recommends that no elective caesarean deliveries should be carried out before 39 completed weeks because of the risk of neonatal respiratory morbidity [7]. This current study was undertaken to determine complication rates for both mothers and neonates from
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