Pregnancy is a dynamic process, which induces a multitude of anatomic, physiological, biochemical, and psychological changes. Physiological changes during pregnancy allow the body to meet the increased metabolic demands of the mother and fetus by maintaining adequate uteroplacental circulation, and ensure fetal growth and development. These changes begin early in the first trimester and are brought on by the increased circulating levels of progesterone and estrogen, which are produced by the ovary in the first 12 weeks of pregnancy and thereafter by the placenta. While some of these cause a change in biochemical values, others may mimic symptoms of medical disease. For instance, cardiac changes such as sinus tachycardia, systolic heart murmurs, and cardiac enlargement could be interpreted as signs of heart disease. It is thus crucial, to differentiate between normal physiological changes and pathological changes, particularly for clinicians involved in the care of pregnant patient.