It has been established that pre-gravid body mass index (BMI) and gestational weight gain (GWG) are associated with adverse obstetric outcomes⁽ Reference Sebire, Jolly, Harris, Wadsworth, Joffe and Beard ^{1 )}. Furthermore, maternal behaviours with regard to dietary intake have been shown to impact on the risk for obesity in offspring⁽ Reference Phelan, Hart, Phipps, Abrams, Schaffner and Adams ^{2 )}. Over-nutrition during pregnancy and the subsequent mismatching of offspring into an obesogenic environment predicate risk. The ‘Barker Hypothesis’ proposes the link between low for gestational age birth-weight and coronary heart disease (CHD)⁽ Reference Barker ^{3 )}. Epidemiological and animal model studies also demonstrate that an adverse inter-uterine environment can effect predictive adaptive responses (PAR) in the fetus resulting in macrosomia and increased risk for obesity, type 2 diabetes mellitus and other non-communicable diseases in later life⁽ Reference Vickers, Krechowec and Breier ^{4 )}. The aim of this study was to investigate the associations between dietary intake in obese pregnant women relative to GWG and infant birth weight (BW). Participants were asked to complete three-day food diaries during each trimester of pregnancy. Data regarding food portion size was verified using a food atlas⁽ Reference Nelson, Atkinson and Meyer ^{5 )} and the diaries were then analysed using Microdiet.

Table 1 Maternal weight and birth weight characteristics with total energy intakes (kcals)

Data were collected for 140 women with a BMI ⩾35 kg/m² and a mean booking in weight of 110.2 kg (sd 15.7). Data shows a moderate mean GWG of<4 kg (sd 14.4), a mean BW of 3.6 kg (sd 0.67). The mean total energy intake is consistent with estimated average requirements for energy during pregnancy. However, a statistically significant negative correlation between energy intake at 36 weeks and BW (rho=−0.249, p=0.033 Spearman's) and a positive correlation between GW at 36 weeks and BW (rho=0.322, p=0.046 Spearman's) was demonstrated. Pregnancy is seen as a key window of opportunity to modify lifestyle behaviours and further research into effective and acceptable interventions, that reduces immediate obstetric risk and long term risk to offspring for obesity, CHD and other dietary related diseases, is needed.