Sleep Disordered Breathing in a High-Risk Cohort Prevalence and Severity across Pregnancy

Abstract

The objective of this study was to determine the prevalence and incidence of sleep disordered breathing (SDB) in pregnancy among high-risk women. This was a prospective, observational study. We recruited women with a body mass index (BMI) ≥ 30 kg/m(2), chronic hypertension, pregestational diabetes, history of preeclampsia, and/or a twin gestation. Objective assessment of SDB was completed between 6 and 20 weeks and again in the third trimester. SDB 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). Subjects who had a normal AHI at the baseline (AHI < 5), but an abnormal study in the third trimester (AHI ≥5) were classified as having "new-onset" SDB. A total of 128 women were recruited. In early pregnancy 21, 6 and 3% had mild, moderate, or severe SDB, respectively. These frequencies increased to 35, 7, and 5% in the third trimester (p < 0.001). About 27% (n = 34) experienced a worsening of SDB during pregnancy; 26 were cases of new-onset SDB, while the other 8 had SDB in early pregnancy that worsened in severity. The incidence of new-onset SDB was 20%. The majority of these new-onset cases were mild. SDB in early pregnancy is common in high-risk women and new-onset SDB occurs in 20% of these women.