Contraception. High blood pressure is two to three times more common in women taking oral contraceptives—especially in obese and older women—than in women not taking them. Also, the longer women take them, the greater the risk of hypertension. That's why your doctor will question you closely about your blood pressure history before prescribing birth control pills, and will want to keep a close watch on your blood pressure when you're taking them. Interestingly, there is no evidence that hormone replacement therapy, which contains significantly less estrogen than oral contraceptives, increases blood pressure.
Pregnancy. Obstetrical visits usually include a blood pressure check. This is to monitor for gestational hypertension, in which your blood pressure rises during pregnancy. High blood pressure problems occur in 6 to 8 percent of all pregnancies in the U.S., about 70 percent of which are first-time pregnancies. In such cases, high blood pressure can harm the mother’s kidneys and other organs, and cause low birth weight and early delivery of the baby. Several blood pressure medications are considered safe to use during pregnancy. And of course, regular exercise can also help women maintain a healthy blood pressure during pregnancy.