Objective assessment of obstructive sleep apnea in normal pregnant and preeclamptic women

Obstructive sleep apnea (OSA) is a risk factor for adverse pregnancy outcomes. The aim of this study was to evaluate the association between OSA and preeclampsia.

Between 30 and 39 weeks gestation, objective sleep apnea were evaluated in 38 normal pregnant and 40 preeclamptic women. Preeclampsia was defined by having a blood pressure (BP) > 140/90 mmHg on two occasions after the 20th week of pregnancy with excess protein in the urine (> 300 mg in 24 h) or 30 mg persistent proteinuria (+ 1 in dipsticks) in random samples. Objective sleep apnea was evaluated using an overnight in-hospital sleep evaluation using the SOMNOwatch plus Respiratory Screener. OSA was defined as an apnea-hypopnea index (AHI) ≥ 5, and further grouped into severity categories: mild (5-14.9), moderate (15-29.9), and severe (≥ 30).

Mean AHI was 33.3 ± 12.1 in preeclamptic women and was 23.8 ± 15.8 in normal pregnant women (p = 0.008). There was significant difference in prevalence of OSA severity (none, mild, moderate, or severe) between groups. Out of 33 preeclamptic women, 11 women had moderate and 22 women had severe OSA. Whereas, among 33 normal pregnant women, 8, 13, and10 women had mild, moderate, and severe OSA, respectively. Two normal pregnant women had no OSA (AHI< 5).

Our study suggests women are susceptible to developing OSA during pregnancy that is associated with an increased risk of preeclampsia.