Expectant mothers at risk for gestational diabetes if they snore, study finds

CHICAGO A new study from researchers at the Northwestern University Feinberg School of Medicine released Friday found that women who reported frequent snoring during their pregnancy were more likely to develop gestational diabetes.

The study also found pregnancy increases the likelihood that a woman will snore.

This is the first study to report a link between snoring and gestational diabetes. Pregnant women who were frequent snorers had a 14.3% chance of developing gestational diabetes, while women who did not snore had a 3.3% chance. Even when researchers controlled for other factors that could contribute to gestational diabetes, such as body mass index, age and race and ethnicity, frequent snoring still was associated with the disease.

Principal investigator Francesca Facco, a fellow at the Feinberg School, presented her findings at the SLEEP 2009 23rd Annual Meeting of the Associated Professional Sleep Societies on June 11.

“Sleep disturbances during pregnancy may negatively affect your cardiovascular system or metabolism,” said Facco. “Snoring may be a sign of poor air flow and diminished oxygenation during sleep, which can cause a cascade of events in your body. 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 study also showed more women became frequent snorers as their pregnancies progressed. Early in pregnancy, 11% of women in the study reported frequent snoring; by the third trimester, the number rose to 16.5%. Frequent snoring was defined as snoring three or more nights a week.

Facco said snoring during pregnancy may be triggered by weight gain and edema (a buildup of fluid), which can increase airway resistance. Exactly how the snoring is linked to gestational diabetes is not yet known.

About 4% of pregnant women develop gestational diabetes, a condition in which women without previously diagnosed diabetes develop high blood sugar levels during pregnancy. Babies born to mothers with gestational diabetes are at increased risk of such problems as being large for gestational age, which may lead to delivery complications. These babies also may have low blood sugar levels and are at increased risk of becoming obese or developing impaired sugar tolerance or metabolic syndrome later in life.

While gestational diabetes usually resolves after pregnancy, women who develop it are at higher risk for Type 2 diabetes later in life.