High blood pressure. Hypertension induced by pregnancy is one of the most common complications of pregnancy, occurring in about 5% of all pregnancies. The definition of hypertension is generally taken to be a blood pressure of 140/90 or greater, although there is not total agreement among physicians about these criteria. Hypertension is an important cause of serious problems in both the mother and the child. Maternal problems include placental abruption, preterm labor, reduced kidney function, and many other problems. Maternal hypertension is also associated with reduced blood flow to the fetus resulting in reduced ability of the fetus to grow (IUGR) and premature birth. Pregnancy-induced hypertension occurs more commonly in older and obese women and in those who have hypertension before pregnancy. Treatment of hypertension in pregnancy varies depending on the severity. Monitoring blood pressure is one of the important functions of the prenatal visit.