*1.2.1 Cardiovascular changes in pregnancy*

Beginning in the first trimester, changes are seen in the cardiovascular system, with cardiac output increasing by 20% as early as the eighth week of gestation [10]. This is mediated primarily by peripheral vasodilation which produces a 25–30% fall in systemic vascular resistance. To compensate for this fall, the heart increases the cardiac output to around 40% throughout pregnancy. This is achieved by a mix of increased stroke volume and heart rate. There is also a compensatory increase in plasma volume to about 50%, with a lesser increase in the red blood cell mass, and a fall in platelet count [11]. Some of these changes also lead to a hypercoagulable state in pregnancy.

Some examination findings may include collapsing pulse and murmur which may be erroneously interpreted as pathological.
