Dyspnea during Pregnancy and Sleep-Disordered Breathing in Pregnancy

Abstract

Dyspnea is so common during pregnancy that it is often referred to as “physiologic” dyspnea. Generally this dyspnea occurs with exercise rather than at rest, but it is not a cause of significant exercise limitation. Although the mechanical impediment of the gravid uterus is often blamed, hyperventilation due to increased progesterone levels probably is the most important mechanism. It is essential to distinguish this physiologic dyspnea from breathlessness caused by disorders complicating pregnancy or diseases that may coexist with pregnancy.

Sleep-disordered breathing is a much less studied phenomenon. Obstructive sleep apnea probably occurs in 1.5 to 2% of the population of child-bearing age. Only few data are available suggesting that pregnancy may cause or exacerbate this disorder, and most cases may simply represent the coexistence of two common conditions. Pregnancy does not appear to cause central sleep apnea. Since hypoxemia can cause intrauterine growth retardation and adverse fetal outcome, sleep-disordered breathing should be treated when of significant degree.

Key Words:

pregnancy - dyspnea - sleep apnea