Frequent snoring during pregnancy increases the likelihood of developing gestational diabetes, according to a recent study from Northwestern University Feinberg School of Medicine. The study also found pregnancy raises the chances that a woman will snore. This is the first study to report a link between snoring and gestational diabetes, which is a condition that may cause health problems for both mother and baby.
“Sleep disturbances during pregnancy may negatively affect your cardiovascular system or metabolism,” said lead investigator Francesca Facco, M.D, of Northwestern Memorial Hospital. “If snoring is bothering a woman who is pregnant, she should seek a consultation with a sleep specialist,” Facco said.
In the study, a cohort of 189 healthy women filled out sleep surveys at six to 20 weeks gestation and in their third trimester. Researchers found that women who were frequent snorers had a 14.3 percent chance of developing gestational diabetes, versus women who did not snore, at 3.3 percent chance. Even controlled for other factors that may influence gestational diabetes such as ethnicity, body mass index, and age, frequent snoring was still associated with the disease.
Metabolic Changes and Diabetes
“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.”
Additionally, the study found more women became frequent snorers as pregnancies progressed. In early stages of pregnancy, 11 percent of those in the study reported frequent snoring, defined as snoring three or more nights a week. When they got to the third trimester, the number rose to 16.5 percent.
According to Dr. Facco, snoring in pregnancy could be triggered by weight gain and edema- buildup of fluid- both of which can raise airway resistance. The mechanism of the snoring and gestational diabetes linkage is not yet understood.
High Blood Sugar Levels
Around 4 percent of pregnant women develop gestational diabetes. In the condition, women who have not previously been diagnosed with diabetes develop high blood sugar levels during pregnancy. Infants born to mothers with gestational diabetes are at higher risk of complications like being large for their gestational age, leading to complications in delivery. They may also have low blood sugar levels and be at higher risk of ultimately becoming obese, or developing metabolic syndrome later in life.
Gestational diabetes usually goes away following pregnancy, however, women who do experience it are at higher risk for type 2 diabetes in later life. Facco said further studies are needed to understand the association between snoring and gestational diabetes and to develop interventions to treat sleep disorders during pregnancy. In a related study, Facco found sleep disturbances such as restless legs syndrome and insomnia also increase notably during pregnancy.
The research abstracts mentioned above were presented at SLEEP 2009, the 23rd Annual Meeting of the Associated Professional Sleep Societies.