Smoking during pregnancy and risk of abnormal glucose tolerance: a prospective cohort study

We utilized data from a prospective cohort of 1,006 Hispanic (predominantly Puerto Rican) prenatal care patients in Western Massachusetts. Women reported pre- and early pregnancy smoking at recruitment (mean = 15 weeks) and mid pregnancy smoking at a second interview (mean = 28 weeks). AGT was defined as > 135 mg/dL on the routine 1-hour glucose tolerance test (1-hr OGTT). We used multivariable regression to assess the effect of pre, early, and mid-pregnancy smoking on risk of AGT and screening plasma glucose value from the 1-hr OGTT.In age-adjusted models, women who smoked > 0-9 cigarettes/day in pre-pregnancy had an increased risk of AGT (OR = 1.90; 95% CI 1.02-3.55) compared to non-smokers; this was attenuated in multivariable models. Smoking in early (OR = 0.48; 95% CI 0.21-1.10) and mid pregnancy (OR = 0.38; 95% CI 0.13-1.11) were not associated with AGT in multivariable models. Smoking during early and mid pregnancy were independently associated with lower glucose screening values, while smoking in pre-pregnancy was not.In this prospective cohort of Hispanic women, we did not observe an association between smoking prior to or during pregnancy and risk of AGT. Findings from this study, although based on small numbers of cases, extend prior research to the Hispanic population.An estimated four to twelve percent of pregnancies are complicated by some degree of abnormal glucose intolerance (AGT), including gestational diabetes mellitus (GDM) as well as milder degrees of glucose tolerance [1]; rates are higher in Hispanic women as compared to non-Hispanic white women. Recently, the 7-year prospective Hyperglycemia and Adverse Pregnancy Outcome study found a consistent, linear increase in risk of adverse perinatal outcomes (cesarean section, fetal size, neonatal hypoglycemia, and fetal hyperinsulinemia) over the entire range of maternal blood glucose levels [2], not just with GDM, suggesting that identifying risk factors for milder degrees of disturbances in glucose