Smoking tobacco during pregnancy is one of the main modifiable risk factors for pregnancy complications. Having pregestational diabetes—that is, having diabetes before becoming pregnant—is the most common chronic condition complicating pregnancy.
Now, the first population-based study to look at the joint effects of smoking and pregestational diabetes during pregnancy, co-authored by Boston University School of Public Health (BUSPH) researchers, finds the increased risk is greater than the sum of its parts.
The study, published in the Journal of Diabetes Research, finds the interaction between tobacco and pregestational diabetes increases the risk of preterm birth by an additional 11.7 percent beyond the risk from each factor added together, and increases the risk of congenital abnormalities by an additional 2.2 percent.
“Our findings are consistent with previous observations that tobacco smoking can have a negative effect on blood sugar levels among diabetic women,” says study co-author Dr. Martha Werler, professor and chair of epidemiology at BUSPH.
To read more about this study, go to: