Cardio-respiratory physiological adaptation of pregnancy.

Significant physiological adaptations during pregnancy contribute to its successful outcome. These occur early in the pregnancy and continue throughout gestation, with complete reversal after delivery. Many changes that are normal during pregnancy are pathological should they occur in the nonpregnant woman. Adequate understanding of these normal changes is essential in the assessment of all pregnancies and in the management of those with complications. This article reviews the cardiovascular and pulmonary changes that occur during a normal gestation.