Background Migration to high income countries can offer socio-economic advantages such as improved education, employment opportunities, housing and health care. However, environmental improvements do not necessarily translate into improved health outcomes. It is possible that the unhealthy lifestyles associated with acculturation, characterised by less physical activity and high calorie energy rich diets, counteract any potential health advantage. Adoption of such lifestyles may be particularly harmful to South Asians who for a given body mass index (BMI), have greater adiposity and an increased risk of diabetes and cardiovascular disease. We explored differences between Pakistani and White British women in relation to socio-economic position, lifestyle characteristics and health related pregnancy characteristics, and investigated whether these differences varied depending on the woman’s, her partner’s and both of their parents’ place of birth.

Methods We examined socio-economic position (employment status; level of education; receipt of benefits; housing tenure), lifestyle characteristics (BMI at the start of pregnancy; smoking during pregnancy) and health related pregnancy characteristics (hypertensive disorders of pregnancy; gestational diabetes; fasting glucose, postload glucose and fasting insulin at ˜27 weeks gestation) of 5038 Pakistani and 4412 White British women recruited to the Born in Bradford cohort study.

Results Pakistani women were less likely to be employed (OR 0.17 95% CI 0.15, 0.19), the difference being markedly less for UK born women. UK born Pakistani women were more likely, and South Asian born less likely, to be educated post 16 than White British women. Smoking was uncommon among Pakistani women. BMI was lower among Pakistani compared to White British women (mean difference -1.12 95% CI -1.43, -0.81) the difference greatest when partners were UK born irrespective of the woman’s place of birth. Pakistani women had higher fasting and postload glucose (mean difference 0.20 95% CI 0.17, 0.24; 0.37 95% CI 0.28, 0.45).

Conclusion Our results suggest that some socio-economic, lifestyle and pregnancy characteristics could be beginning to change in response to migration to the UK and that these changes can be both positive i.e. improving education and employment prospects and no evidence that being UK born has further increased the risk of Gestational Diabetes Mellitus, and negative i.e. slight increases in smoking.