This content was created by the National Sleep Foundation

A new study appearing in the January issue of SLEEP suggests that treatment of mild-sleep disordered breathing with continuous positive airway pressure (CPAP) therapy in pregnant women with preeclampsia improves fetal activity levels.

Preeclampsia affects about five percent of pregnancies and is dangerous for the mother as well as a risk factor for fetal growth restriction. It involves the onset of high blood pressure and protein in the urine after 20 weeks into the pregnancy.

The study had three parts. The study began with the validation of a fetal activity monitor against ultrasound in 20 normal pregnant women in their third-trimester. Next, fetal movement was measured in 20 women while they slept with moderate to severe preeclampsia and 20 matched control subjects. Results showed fetal movement was lower in the preeclampsia group than the control group.

In the final phase, fetal movement was measured on consecutive nights in 10 women with moderate to severe preeclampsia. The first night, the women slept as they normally would. The second night, they received nasal CPAP therapy.

The results of the study show that the average number of fetal movements increased from 319 during a night without CPAP therapy to 592 with CPAP therapy. Without CPAP therapy, fetal movements were recorded at a little over seven movements per hour. With CPAP therapy, the movements increased to a little over 12 movements per hour.

The study’s principal investigator, Colin Sullivan, PhD, said, “What would otherwise have been considered clinically unimportant or minor ‘snoring’ likely has a major effects on the blood supply to the fetus, and that fetus in turn protects itself by reducing movements.” Sullivan believes this can be treated with available PAP machines and suggests that measuring fetal activity during the mother’s sleep is important.

In a commentary on the study, associate professor at the University of Michigan, Louise M. O’Brien, PhD, MS said, “Maternal SDB represents a unique opportunity to study the effect of in utero exposures on postnatal development and future risk. This has major implications for public health. It raises the possibility that a simple, noninvasive therapy for SDB may improve fetal well-being.”