Obstructive sleep apnea and pregnancy: the effect on perinatal outcomes.

Obstructive sleep apnea (OSA) is characterized by repeated episodes of upper airway obstruction, resulting in hypoxemia, hypercapnia and sleep fragmentation. Pathophysiological sequelae include sympathetic activation, increased oxidative stress and a generalized inflammatory response, culminating in endothelial dysfunction. These are the proposed mechanisms that mediate the increased risk of hypertension and cardiovascular disease among patients with OSA outside of pregnancy. It is intriguing to consider the consequences of these events on pregnancy outcomes. There is a growing literature on the impact of maternal OSA on hypertensive disorders of pregnancy, gestational diabetes and impaired fetal growth. The data, while promising, require confirmation with larger numbers to verify the findings. OSA may be an important mediator of the poor perinatal outcomes associated with maternal obesity; moreover, one which may be amenable to treatment. This review discusses OSA and summarizes the current literature linking OSA with adverse perinatal outcomes.