Inconsistent information exists in the relationship between obstructive sleep apnea (OSA) and perinatal outcomes. This study was intended to investigate whether OSA in pregnant women has a potential to elevate the incidence of the maternal and neonatal outcomes by performing a meta-analysis of all available cohort studies. Five cohort studies including 977 participants were eligible for inclusion. The association between OSA and the risk of perinatal outcomes was expressed as relative risks (RR), with 95% confidence interval (CI). Our results revealed that OSA group was associated with more frequent preeclampsia (RR 1.96; 95% CI 1.34 to 2.86), preterm birth (RR 1.90; 95%CI 1.24 to 2.91), cesarean delivery (RR 1.87; 95% CI 1.52 to 2.29) and neonatal intensive care unit (NICU) (RR 2.65; 95% CI 1.86 to 3.76). On analyzing data for the prevalence of gestational diabetes and small gestational age (SGA) , 10th percentile (RR 1.40; 95% CI 0.62 to 3.19, and RR 0.64; 95%CI 0.33 to1.24, respectively), there were no significant differences in both group. Findings from this meta-analysis indicate that OSA in pregnant women significantly increases the incidence of maternal and neonatal outcomes, which is associated with more frequent preeclampsia, preterm birth, cesarean delivery and NICU admission.