Obesity in pregnancy: Infant health service utilisation and costs on the NHS

Objective: To estimate the direct healthcare cost of infants born to overweight or obese mothers to the National Health Service in the UK. Design: Retrospective prevalence-based study. Setting: Combined linked anonymised electronic data sets on a cohort of mother-child pairs enrolled on the Growing Up in Wales: Environments for Healthy Living (EHL) study. Infants were categorised according to maternal early-pregnancy body mass index (BMI): healthy weight mother (18.5≤BMI<25 kg/m2; n=342), overweight mother (25≤BMI≤29.9 kg/m2; n=157) and obese mother (BMI≥30; n=110). Participants: 609 singleton pregnancies with available health service records and an antenatal maternal BMI. Primary outcome measure: Total health service utilisation and direct healthcare costs for providing these services in the year 2012-2013. Costs are calculated as cost of the infant (no maternal costs considered) and are related to health service usage from birth to age 1 year. Results: A strong association existed between healthcare usage cost and BMI ( p<0.001). Mean total costs were 72% higher among children born to obese mothers (rate ratio (RR) 1.72, 95% CI 1.71 to 1.73) compared with infants born to healthy weight mothers. Higher costings were attributed to a significantly greater number (RR 1.39, 95% CI 1.04 to 1.84) and duration (RR 1.55, 95% CI 1.37 to 1.74) of inpatient visits and a higher number of general practitioner visits (RR 1.10, 95% CI 1.03 to 1.16). Total mean additional resource cost was estimated at £65.13 for infants born to overweight mothers and £1138.11 for infants born to obese mothers, when compared with infants of healthy weight mothers. Conclusions: Increasingly infants born to mothers with high BMIs consume additional health service resources in the first year of life; this was apparent across inpatient and general practitioner services. Considering both maternal and infant health service use, interventions that cost less than £2310 per person in reducing obesity early pregnancy could be cost-effective.