Mounting evidence supports the negative consequences of OSA on maternal-fetal health. Snoring and OSA in pregnancy are associated with increased risk of gestational diabetes mellitus, preeclampsia, and pregnancy induced hypertension (OR 7.5). Even non-obese pregnant women with OSA symptoms have a 6.6 odds for preeclampsia. Cyclical hypoxemia and re-oxygenation promote pro-inflammatory markers that underlie these conditions. Habitual snoring is associated with increased cord blood levels of nucleated red blood cells, interleukin-6, and other inflammatory markers. Future studies are needed to identify the frequency and severity of sleep related breathing disorders required to confer adverse pregnancy outcomes.