Background: Australia has one of the highest rates of overweight and obesity in the developed world1. Obesity in pregnancy presents a major public health issue due to the increase in short and long term adverse outcomes for mothers and their babies. Awareness of its impact is of particular importance in non-urban populations where disparities in health outcomes already exist2. The incidence over time and impact of maternal overweight and obesity has been poorly evaluated due to limitations in standardised data collection and reporting3.
Aim: We have conducted a seven-year monotonic trend analysis of pregnancy outcomes, utilising healthcare provider collected body mass index (BMI), reported in gradients of WHO BMI class.
Methods: Maternal and neonatal information was retrospectively collected from the Birthing Outcome System (BOS) at a level 5 maternity service in regional Victoria. Prevalence of comorbidities, antenatal, intrapartum and postpartum complications were compared. Trends over time were evaluated for maternal BMI class, gestational diabetes and delivery mode.
Results: Between January 2010 and December 2016, 6 661 women contributed to 8 838 deliveries. Of these women 29.3% were classed as obese (BMI ≥30) and a further 27.5% as overweight (BMI 25-30). Those who were overweight or obese were more likely to present with preexisting comorbidities and develop maternal and neonatal complications. There was both a significant trend over time in the number of pregnant women with a BMI>35, and a decreased in those with normal weight. There was an increasing incidence of gestational diabetes over time, which increased per increment of BMI category. There was also an overall significant decreased in the vaginal birth rate in the population over time.
Conclusion: Given the far reaching impact of maternal obesity and unique opportunity for preventative health interventions in pregnancy our research highlights the importance of ensuring regional health services are well resourced to deliver care tailored to the population they are serving to ensure sustainable and effective maternity health services.