Objective: To investigate the effect of maternal body mass index (BMI) on minor complications, associated additional medication use during pregnancy and the consequent cost implications.
Design: Retrospective analysis of case notes.
Setting: Labour wards, tertiary referral hospital, Royal Infirmary Edinburgh, UK. Population Six hundred and fifty-one women with a singleton pregnancy over four separate time periods in 2007 and 2008.
Methods: Descriptive statistics, univariate and multivariate logistic regression analysis and cost analysis using standard techniques and inflation indices.
Main outcome measures: Minor complications, use of medications during pregnancy and consequent incremental costs from the perspective of the National Health Service (NHS).
Results: 42.4% of women were overweight or obese (BMI > or = 25 kg/m(2)). Higher BMI during the first trimester (BMI > or = 30 kg/m(2) compared with BMI < 25 kg/m(2)) was associated with an increased risk of minor complications including symphysis pubis dysfunction (OR 3.97; 95% CI 2.19-7.18), heartburn (OR 2.65; 95% CI 1.42-4.94) and chest infection (OR 8.71; 95% 2.20-34.44) and with drugs used to treat these complications including Gaviscon (OR 3.52; 95% CI 1.78-6.96). The mean incremental (additional) NHS costs per woman for treating minor complications increased with maternal BMI were 15.45 pounds/woman, 17.64 pounds/woman and 48.66 pounds/woman for BMI < 25 kg/m(2), BMI > or = 25 to <30 kg/m(2) and BMI > or = 30 kg/m(2) respectively.
Conclusions: Increased maternal BMI is associated with increased risk of developing minor complications during pregnancy; use of medications associated with treating these conditions and has significant NHS costs.