Pregnant women who snore are more likely to develop gestational diabetes - a condition than can cause health problems for the mother and baby.
The study from researchers at the Northwestern University Feinberg School of Medicine also found that pregnancy increases the likelihood that a woman will snore.
To reach the conclusion, 189 healthy women completed a sleep survey at the time of enrollment (six to 20 weeks gestation) and in the third trimester.
Pregnant women who were frequent snorers had a 14.3 percent chance of developing gestational diabetes, while women who did not snore had a 3.3 percent chance. Even when researchers controlled for other factors that could contribute to gestational diabetes such as body mass index, age, race and ethnicity, frequent snoring was still associated with the disease.
Principal investigator Francesca Facco, M.D., a fellow at Northwestern's Feinberg School, will present her findings at the SLEEP 2009 23rd Annual Meeting of the Associated Professional Sleep Societies.
"Sleep disturbances during pregnancy may negatively affect your cardiovascular system or metabolism," said Facco, who in August will become an assistant professor of obstetrics and gynecology at the Feinberg School and a maternal and fetal medicine physician at Northwestern Memorial Hospital.
"Snoring may be a sign of poor air flow and diminished oxygenation during sleep that can cause a cascade of events in your body," Facco said.
"This may activate your sympathetic nervous system, so your blood pressure rises at night. This can also provoke inflammatory and metabolic changes, increasing the risk of diabetes or poor sugar tolerance," the expert added.
The study also showed more women became frequent snorers as their pregnancies progressed. Early in pregnancy, 11 percent of women in the study reported frequent snoring; by the third trimester, the number rose to 16.5 percent. Frequent snoring was defined as snoring three or more nights a week.