Effect Study of Physiological changes of a Pregnant Woman
Keywords:Pharmacokinetic, vasodilatory, consumption, upregulated, proteinuria.
Understating these changes and their profound impact on the pharmacokinetic properties of drugs in pregnancy is
essential to optimize maternal and fetal health. During normal pregnancy, the renin–angiotensin system (RAS) plays a
vitally important role in salt balance and subsequent well-being of mother and fetus. In this balance, one must consider not
only the classical renal RAS but also that of the uteroplacental unit, where both maternal and fetal tissues contribute to the
signaling cascade. Many studies have shown that in normal pregnancy there is an increase in almost all of the components
of the RAS. In derangements of pregnancy this delicate equilibrium can become unbalanced. Preeclampsia is one such
case. It is a disorder of pregnancy characterized by hypertension, proteinuria and placental abnormalities associated with
shallow trophoblast invasion and impaired spiral artery remodeling. Changes in the cardiovascular system in pregnancy
are profound and begin early in pregnancy, such that by eight weeks’ gestation, the cardiac output has already increased
by 20%. The primary event is probably peripheral vasodilatation. This is mediated by endothelium-dependent factors,
including nitric oxide synthesis, upregulated by oestradiol and possibly vasodilatory prostaglandins (PGI2). There is a
significant increase in oxygen demand during normal pregnancy. This is due to a 15% increase in the metabolic rate and
a 20% increased consumption of oxygen.