The functional and subjective changes in the mother around her pregnancy are profound and may resemble signs and symptoms of diseases. Equally impressive is the quick return to a pre-pregnancy situation after delivery. These adaptations affect nearly every organ system and are essential for normal maternal pregnancy and normal foetal development. Changes in eating habits are one of the first physiological symptoms of pregnancy. During pregnancy, the maternal body weight increases by on average 12 kg. The importance of the placenta is well recognized. Pregnancy is characterized by a
hyperdynamic cardiovascular state. Peripheral insulin resistance becomes more prominent during pregnancy making pregnancy a state of hyperinsulinism with increased glucose levels. Respiration is more efficient during pregnancy, although most pregnant women have a subjective feeling of mild
dyspnoea. From early pregnancy onwards there is a substantial increase in renal plasma flow. Nowadays the importance of the human
microbiome for normal development of pregnancy is well realized.