Obstructive sleep apnea is a common medical condition characterized by periodic apneas during sleep that produce hypoxia and sleep disruption. Several cases of obstructive sleep apnea in pregnancy have been reported. In the case reported the woman admitted for evaluation and management of preeclampsia was observed experiencing apneic episodes and oxygen desaturation during sleep. Subsequent evaluation confirmed the diagnosis of obstructive sleep apnea. Pregnancy may be complicated by obstructive sleep apnea with potential adverse effects on the mother and fetus. Prompt diagnosis would allow early treatment and may prevent low birth weight and the development of preeclampsia.