Pregnant women with this sleep disorder more likely to have high blood pressure after giving birth

 By Stephen Beech via SWNS

Pregnant women who snore could be three times more likely to suffer from high blood pressure after giving birth, suggests a new study.

All moms-to-be are at an increased risk of obstructive sleep apnea because higher levels of the hormone estrogen during pregnancy can cause the mucus membranes in the nose to swell, leading to nasal congestion.

Around one in 12 pregnant women suffer from the condition, according to previous research.

For the new study, American researchers examined whether sleep disordered breathing - primarily obstructive sleep apnoea - during pregnancy and in the years after giving birth is associated with an increased risk for hypertension and metabolic syndrome, which consists of a cluster of conditions that increase the risk of heart disease, stroke and diabetes.

Study lead author Dr. Francesca Facco and colleagues conducted sleep apnea tests on more than 1,900 women during their first pregnancy, and on 1,222 of the same group two to seven years after giving birth.

The research team then determined whether participants were at increased risk for hypertension or metabolic syndrome.

Dr. Facco, an Assistant Professor at University of Pittsburgh Medical Center, said: “While epidemiologic data from cohorts of middle-aged and older adults indicate that sleep disordered breathing is associated with adverse cardiometabolic outcomes, less is known about how sleep-disordered breathing in pregnancy and in the post-delivery period impacts maternal health.

"Sleep disordered breathing during pregnancy has been associated with a two- to three-fold increased risk for pre-eclampsia -persistent high blood pressure during pregnancy that can lead to serious health consequences - and/or gestational diabetes.

"These and other adverse pregnancy outcomes are risk factors for later development of hypertension and metabolic disease in the mother."

The participants were tested both during pregnancy and two to seven years later, each using the same model home sleep apnoea test.

Among other factors, sleep apnoea tests measure the number of times a person experiences breathing pauses and associated drops in oxygen levels.

The participants were considered to have sleep apnoea if they experienced five or more breathing pauses or drops in oxygen during their estimated sleep period.

Dr. Facco said: “We found that the presence of sleep apnea measured both during pregnancy and two to seven years after delivery was associated with the development of hypertension and metabolic syndrome."

The findings also showed that participants with sleep apnea that persisted during pregnancy and the two to seven year follow-up visit were at more than three-fold increased risk for incident hypertension and a more than two-fold increased risk for metabolic syndrome compared to participants who never had an abnormal sleep study.

Incident hypertension is defined as the first occurrence at any follow-up visit of systolic blood pressure 140 mm HG or higher or diastolic blood pressure 90 mm HG or higher.

Study co-author Dr. Susan Redline, of Brigham and Women’s Hospital and Harvard Medical School, said: “Our data also demonstrated a higher risk of developing metabolic syndrome and hypertension using a simple measurement of oxygen dips per hour of sleep.

“These results suggest that use of simple oxygen monitoring devices may be useful for identifying women in pregnancy and in the post-delivery period at risk for adverse health outcomes and identifying women who may potentially benefit from treating sleep apnea.”

Dr. Facco added: “These data underscore the need to rigorously evaluate the role of screening and treating sleep apnea during pregnancy and in the post-delivery period as new strategies for early interventions aimed at improving long-term maternal health."

The findings were published in the American Journal of Respiratory and Critical Care Medicine.