Pregnancy-Induced Hypertension (PIH)

Pregnancy is a joyful time for most mothers: it can be exciting, fun, and gives you lots to look forward to. But pregnancy also comes with a lot of responsibility, including frequent visits to your health care practitioner. Now that you are pregnant you have probably noticed that your health care providers are frequently checking your blood pressure. Blood pressure must be monitored during pregnancy because of a condition called pregnancy-induced hypertension. If you are pregnant, be sure that you get your blood pressure levels checked out frequently to avoid developing this condition.

What is Hypertension in Pregnancy?
Pregnancy-induced hypertension is a condition that causes elevated blood pressure in a mother-to-be. In order to be diagnosed with pregnancy-induced hypertension, your blood pressure levels must be higher than 140/90 mmHg during the last half of your pregnancy. Pregnancy-induced hypertension can be quite serious as it can lead to various complications both for you and your baby. In fact, preeclampsia and eclampsia, severe forms of pregnancy-induced hypertension, are the leading cause of infant and maternal death in the United States.

Also called toxemia and gestational hypertension, pregnancy-induced hypertension is found in about 5% to 10% of all pregnancies in the United States. It is the most common medical problem associated with pregnancy but there is no known cause or cure for the condition. However, there are specific symptoms of hypertension in pregnancy. If you notice these hypertension symptoms, speak with your health care provider immediately.

What causes Pregnancy-Induced Hypertension?
To date, there is no known cause for pregnancy-induced hypertension. It is thought that the condition may begin in early pregnancy, during embryo implantation. Generally, blood vessels in the uterus stay relaxed during implantation and pregnancy. People with pregnancy-induced hypertension appear to have abnormally constricted blood vessels but often have no history of heart disease. This could be the cause of hypertension.

Risk Factors for Pregnancy-Induced Hypertension
Though the cause for pregnancy-induced hypertension is unknown, there does appear to be certain risk factors associated with the condition. These include:


  • having your first baby before the age of 20 or after 35
  • having a history of diabetes
  • having a history of hypertension (high blood pressure) before pregnancy
  • having multiple births (twins, triplets etc.)
  • being of African descent


Types of Pregnancy-Induced Hypertension
There are three main types of pregnancy-induced hypertension:

Gestational Hypertension: Gestational hypertension is the most common form of hypertension in pregnancy. It is diagnosed if a woman’s blood pressure is higher than 140/90 in the last half of her pregnancy. No other signs or symptoms accompany this type of hypertension.

Preeclampsia: Preeclampsia is a more serious form of pregnancy-induced hypertension. It is diagnosed when a mother’s blood pressure is higher than 140/90 in the last 20 weeks of pregnancy, and when protein is found in urine samples.

Eclampsia: Eclampsia is one of the most serious forms of pregnancy-induced hypertension. It causes convulsions or coma in the late stages of pregnancies.

Symptoms of Pregnancy-Induced Hypertension
All expectant mothers should be aware of pregnancy-induced hypertension symptoms. These include:


  • blood pressure readings above 140/90, or significantly higher than normal
  • protein found in the urine (caused by damaged kidney filter)
  • edema (swelling), especially in the face and neck
  • sudden weight gain
  • blurred or double vision
  • headache
  • seeing flashing lights or spots
  • urinating only small amounts
  • abdominal pain
  • nausea and dizziness


Complications Associated with Pregnancy-Induced Hypertension
Pregnancy-induced hypertension can be very dangerous for both you and your baby. If left untreated, it can easily worsen, leading to severe preeclampsia or eclampsia. Effects of pregnancy-related hypertensions include:


  • leaky blood vessels, leading to swelling and weight gain
  • leaky vessels in the lungs, causing shortness of breath
  • leaking liver vessels, causing swelling and liver damage
  • protein leaks in the kidneys, which can lead to low birth weight babies


Typically, these complications will disappear after your baby is born, however, damage to the organs can still result. Some of the most serious complications of pregnancy-induced hypertension include:


  • blindness, liver rupture, and kidney failure in the mother
  • placental abruption, in which the placenta separates from the uterus possibly resulting in stillbirth
  • brain damage to mom, caused by swelling, convulsions, and coma
  • HELLP syndrome, which can destroy the body’s red blood cells, liver, and stops the blood from clotting


There is no known cure for pregnancy-induced hypertension. Some doctors will prescribe micardis, a drug which can help decrease hypertension.  If hypertension occurs late in your pregnancy, your health care provider may suggest bed rest and increased blood pressure monitoring. Certain hypertension medications may also be prescribed. Usually, delivery is the best treatment for pregnancy-induced hypertension. Once your baby is born, symptoms of the condition disappear. Labor may be induced or a c-section performed. If hypertension occurs early in pregnancy you health care provider will suggest that you weigh the risks and benefits of carrying to term or having an early cesarean section.

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my doctor says my blood pressure is a bit high although not yet preeclampsia. i am currently 34 weeks pregnant. my doctor wants me to measure my blood pressure everyday at home and to come in twice a week for testing. if it becomes worse or preeclampsia then we will have to look into doing a planned c-section. none of this news is helping my blood pressure because it is making me more stressed out. need to find a way to relax.
13 years ago