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
