I've blogged before here, here, and here about pregnancy and breathing disorders in sleep. We know that the prevalence of sleep-disordered breathing (SDB) symptoms increases the further along in the pregnancy. This could be due weight gain and swelling that occurs as pregnancy progresses.
Some studies have shown an association between SDB and pregnancy-related illnesses like high blood pressure, gestational diabetes, and pre-term birth. However, many of these studies relied on subjective assessment of SDB. This study was done to look at the relationship of objectively assessed SDB and certain pregnancy-related illnesses. A home sleep study was performed on pregnant women twice - once between 6 - 20 weeks and again between 28 - 37 weeks. Results showed that 30% of the pregnant women had SDB early pregnancy. However, there was no relationship between SDB and maternal high blood pressure (called preeclampsia), preterm birth, or extremes of birthweight (low or high). There was a relationship between SDB severity and risk of developing gestational diabetes, even after controlling for confounding factors like age, race, body-mass index, hx of chronic high blood pressure, etc.
Despite the observed relationship between sleep-disordered breathing and gestational diabetes, the study authors pointed out that there is no evidence that treatment of the SDB in the short term improves maternal or neonatal outcomes.