High blood pressure can exist before pregnancy or a woman can develop it during pregnancy. Blood pressure that is only slightly elevated may be treated with rest, increased prenatal checkups, reduction of salt intake and increased fluid intake explains the American Pregnancy Association. The baby may be induced or delivered via cesarean in moderate cases or if the woman is close to term. Medications can treat severe preeclampsia or when the baby is not fully developed.
Beta Blockers
Nearly all high blood pressure medications are classified as a category C risk by the Food and Drug Administration. This means that studies on animals show an adverse effect on the fetus but an adequately controlled study has not occurred or replicated the same results in humans, explains SafeFetus.com. With this type of rating, physicians should only give beta-blockers when the potential risk to the baby outweighs the risk of going without treatment. An example of this would be if the mother has extremely high and uncontrollable blood pressure but the fetus is too immature to deliver.
Some examples of beta-blockers with a category C rating include metoprolol and metoprolol tartrate. These drugs work by impacting the heart and circulation to reduce pressure, explains Drugs.com. Some beta-blockers have a category D rating or below and physicians won't prescribe them for a pregnant woman.
Calcium Channel Blockers
Many calcium channel blockers also have a category C rating according to SafeFetus.com. These drugs work by dilating blood vessels to slow the heart, which reduces blood pressure, explains Drugs.com. SafeFetus.com reports that one such drug, amlodipine besylate, has been shown to increase intrauterine deaths, prolonged labor and gestation in animals.
Diuretic
Diuretics also have a category C rating according to SafeFetus.com. These medications work by preventing the body from absorbing too much salt and encouraging the salt to leave the body via the urine, as indicated by Drugs.com. One such drug, furosemide, was found to increase fetal urine production and to potentially be linked with an improperly located urethra, or urinary opening, suggests SafeFetus.com. These risks diminish after the first trimester, when their use appears to have minimal severe effects on the baby.
