Ten percent of mothers report smoking cigarettes during the last three months of their pregnancy, according to the Centers for Disease Control and Prevention (CDC). By stifling their baby’s oxygen supply with dangerous chemicals, they run the risk of various health problems not only for their child but also for themselves. Adding to that list is a higher risk of type 2 diabetes in women who were exposed to smoking while they were in their mothers’ wombs.

Dr. Michele La Merrill, an assistant professor in the Department of Environmental Toxicology at the University of California, Davis, and her team found that fetal exposure to smoking among girls, specifically when it was the mother smoking, increased those girls chances of developing type 2 diabetes as adults. These findings held even when the researchers accounted for factors such as the parents’ race, employment, and their own diabetes status.

“From a public health perspective, reduced fetal environmental tobacco smoke exposure appears to be an important modifiable risk factor for diabetes mellitus in offspring,” La Merrill said in a press release. “Medical doctors should consider advising pregnant smokers that emerging research suggests that tobacco cessation in the home may benefit offspring by reducing their risk of developing diabetes mellitus independent of the effects of adult body mass index or birth weight on diabetes risk.”

Cigarette smoke contains over 7,000 chemicals, all of which reach the growing fetus in the womb. This exposure can cause everything from a miscarriage to a low birth weight and problems with the placenta — the fetus’ main food and oxygen source — to birth defects like cleft palate. Studies have also linked exposure to cigarette smoke both in an out of the womb to weight gain, which is a known risk factor for diabetes.

For their study, La Merrill and her team looked at data from the Child Health and Development Studies, which seeks to determine the relationships between prenatal exposures and parental and child health outcomes over three generations. Their data set included 1,801 diabetic daughters aged 44 to 54 whose moms had reported smoking during an early pregnancy interview. They looked into parental smoking during pregnancy, race, occupation, and a number of other factors, and interviewed the daughters and took blood samples to see how well they were managing their diabetes.

While the study didn’t prove a causative effect, the findings should still come as a warning to pregnant mothers that smoking is wildly dangerous to the their baby — and of course themselves, too.

Source: La Merrill M, et al. At ENDO 2015.