Prospective trial on obstructive sleep apnea in pregnancy and fetal heart rate monitoring

Objective

Obstructive sleep apnea (OSA) involves episodic nocturnal apneas. Using polysomnography, we examined the predictive capacity of screening questionnaires (Berlin) in pregnancy. Incorporating simultaneous fetal heart rate monitoring (FHM), we examined the association of maternal apnea with FHM abnormalities.

Study Design

We enrolled 100 pregnant women at 26-39 weeks of gestation with OSA screening and baseline data ascertainment who underwent polysomnography and FHM for ≥3 hours. The relationship between maternal characteristics, OSA, and FHM was explored with multivariate analyses that were controlled for potential confounders.

Results

When compared with polysomnography, sensitivity and specificity by Berlin screening was 35% and 63.8%, respectively; the snoring component of the Berlin correlated better with oxygen desaturation <95% (P = .003). Body mass index was a significant confounder (r_s = 0.44; P < .0001). No association was observed between FHM abnormalities and OSA parameters.

Conclusion

In pregnancy, the Berlin questionnaire poorly predicts OSA. It is unclear whether fetal compromise during maternal apnea is a mechanism in OSA that is related to pregnancy outcome.

Key words: fetal heart rate monitoring, obstructive sleep apnea, polysomnography, pregnancy