Obstructive sleep apnea is characterized by total or partial interruptions of airflow during sleep, despite ongoing efforts to breathe. These pauses result from repeated upper airway obstructions that generate a systemic inflammatory condition with consequences for the endothelial function that increase the risk of cardiometabolic events. The prevalence of obstructive sleep apnea during pregnancy is greater than that observed in the general population and increases in the third trimester. Although limited, the information currently available supports the notion that obstructive sleep apnea is an independent, and potentially modifiable, risk factor for maternal and perinatal morbidity and mortality. Experimental and prospective studies in humans have demonstrated an association between obstructive sleep apnea and low birth weight. Endothelial dysfunction may be the link that underlies the association of obstructive sleep apnea with high perinatal risk. The information reviewed herein suggests that treating obstructive sleep apnea with positive-pressure devices could be an effective strategy for decreasing perinatal morbidity and mortality.