Smoking during pregnancy and diabetes mellitus in a British longitudinal birth cohort

Exposures in utero may increase the risk of type 2 diabetes. 1 2 We tested the hypothesis that maternal smoking during pregnancy increases both the risk of early onset type 2 diabetes3 and non-diabetic obesity in offspring. We used data are from the British National Child Development Study (NCDS),4 based on the Perinatal Mortality Survey (PMS) of about 17 000 births from 3 to 9 March 1958. The first sweep of the study in 1965 had 15 396 responses. The cohort remained generally representative at age 33 years (n=11 359).5 Missing data reduced the proportion in social class V from 6.4% in sweep 1 to 5.3%. Ethics committee approval was obtained for research involving medical examinations, and cohort members signed consent forms at age 33 years allowing access to medical records. …