A profile of body mass index in a large rural Victorian obstetric cohort

Objectives: To report on the prevalence and implications of overweight and obesity in a rural maternity cohort. Design, setting and participants: A retrospective 6-year cohort of 6138 pregnancies managed in a rural Victorian maternity service from 1 January 2005 to 31 December 2010. Main outcome measures: Maternal body mass index (BMI), prevalence of overweight and obesity, prevalence of pregnancy complications and their association with BMI class. Results: A total of 65.6% of all women were overweight or obese. Only 32.7% of the women were of normal/healthy weight; 1.6% were underweight, 33.0% were overweight, 18.6% were obese class I, 8.3% obese class II and 5.7% were obese class III. Increased BM was associated with increased rates of induction of Labour, gestational diabetes mellitus, pregnancy-induced hypertension, operative vaginal deliveries, caesarean sections, invasive fetal monitoring, increased gestational age at delivery, increased birth weight, and increased maternal length of stay (P < 0.01 for all). Analysed separately, 60.5% of first-time mothers were overweight or obese. Conclusions: Almost two-thirds of this rural maternity cohort were overweight or obese; twice the level reported from metropolitan centres and higher than other Australian reports. The associations with complications are similar to those reported previously. This high rate of maternal overweight and obesity may have implications for rural maternity funding, outcomes and perinatal mortality rates.