High Blood Pressure and Pregnancy: What You Need to Know

High Blood Pressure and Pregnancy: What You Need to Know

From the time you conceive until after you give birth, your body undergoes a lot of changes. While blood pressure may mildly fluctuate during this time, it is important to make sure your numbers don’t get too high or too low.

pregnant woman


The American Heart Association (AHA) sets the standards for blood pressure readings, which include the following:

  • Low — 90/60 mm Hg and below
  • Normal — 120/80 mm Hg
  • High — 140/90 mm Hg and up

In the United States, about 10 percent of pregnancies have issues with high blood pressure. If you have an abnormal blood pressure reading while pregnant, talk to your doctor. An easy way to keep track of your blood pressure is with a digital blood pressure monitor

What is Abnormal Blood Pressure When You’re Pregnant?

When you are pregnant, high blood pressure is anything 140mm Hg or more systolic, and 90 mm Hg or more diastolic. This means 140/90 mm Hg or more is considered high blood pressure.


If you have high blood pressure during your pregnancy, you and your baby have a higher chance of experiencing complications. Some complications include:

  • Preeclampsia and eclampsia
  • Placental abruption
  • Fetal growth issues
  • Cesarean delivery
  • Preterm delivery

Low blood pressure during pregnancy can also cause problems. Some of the complications with hypotension during pregnancy include:

  • Vaginal bleeding
  • Vomiting
  • Anemia
  • Nausea

Symptoms of High Blood Pressure During Pregnancy

How do you know if you have high blood pressure during pregnancy? Along with taking your blood pressure with a portable blood pressure monitor, watch out for the following:

  • Vision changes
  • Nausea and vomiting
  • Abdominal pain
  • Shortness of breath
  • Headaches
  • Swelling in your hands or feet
  • Flushed skin

Symptoms of Low Blood Pressure During Pregnancy

Low blood pressure, also called hypotension, can cause symptoms as well. The symptoms of hypotension during pregnancy include:

  • Extreme fatigue
  • Sudden tiredness
  • Depression
  • Rapid breathing
  • Blurred vision
  • Cold, clammy skin
  • Difficulty concentrating
  • Dizziness

If you have any symptoms in either category, it is important to talk to your doctor. If you are consistently experiencing symptoms, it is a good idea to keep an eye on your numbers with a blood pressure monitor. Many at-home monitors are accurate, and you can track your information for your doctor so they can make better decisions when it comes to your health.

Causes of Abnormal Blood Pressure

Now that you know what is considered abnormal blood pressure and the symptoms, we are going to talk about what causes it.

High Blood Pressure

If you develop high blood pressure during the first 20 weeks of pregnancy, you may be diagnosed with chronic hypertension. Your high blood pressure could continue after birth. Factors that put you at higher risk for hypertension include:

  • Obesity
  • Over 35 years of age
  • Underlying health problems
  • Not enough physical activity
  • IVF
  • Diabetes or autoimmune diseases
  • First-time pregnancy
  • Carrying more than one child

Low Blood Pressure

Low blood pressure is different because it is more common during pregnancy. As your body accommodates your new baby, it is common to experience. Hypotension can also be caused by:

  • Lack of vitamin D, vitamin B, and folic acid
  • Infection
  • Blood loss
  • Allergic reaction
  • Thyroid issues
  • Heart problems
  • Low blood sugar
  • Diabetes
  • Dehydration

Gestational Hypertension

If you have high blood pressure after 20 weeks of pregnancy and it resolves after you give birth, then you may be diagnosed with gestational hypertension. If you are diagnosed with this before 30 weeks, there is a higher chance you will experience preeclampsia during your pregnancy as well.

How to Treat Abnormal Blood Pressure While You’re Pregnant

Once you identify your symptoms and are diagnosed with abnormal blood pressure during pregnancy, it is time to talk about treatment options with your doctor. 


If you have high blood pressure, your doctor will closely monitor you and your baby by blood tests, urine tests, and fetal monitoring. Ultrasounds will also be performed more regularly to ensure your baby is developing properly. 

Your doctor may recommend you start taking blood pressure medications if your blood pressure starts getting out of control.


If you are experiencing hypotension, you can try:

  • Taking breaks from standing
  • Sit more frequently
  • Eat more salt
  • Wear compression socks
  • Drink more water

Keep an eye on your blood pressure numbers as you go through your pregnancy. It will help you and your doctor figure out what works, what doesn’t work, and help you both make the right decisions for you and your child.

Can You Prevent Abnormal Blood Pressure?

While you can’t really prevent abnormal blood pressure during pregnancy, you can lower your risk of complications. Before getting pregnant, head to your doctor to talk about your family medical history and risk factors you may have. 

The American College of Obstetricians and Gynecologists have said there are no proven ways to keep hypertension from happening during pregnancy. However, there are some things you can do to live a healthy lifestyle to lower the risk of complications:

  • Exercise three times a week
  • Quit smoking
  • Limit alcohol intake
  • Manage health conditions
  • Eat a healthy diet
doctor in office

Blood Pressure Changes in Pregnancy

When you are pregnant, the amount of blood in your body increases. In fact, it can increase as much as 45 percent. Since there is extra blood, it means your heart has to work harder to pump the blood through your body. Your kidneys also work harder while you’re pregnant. They release vasopressin, which is a hormone that makes your body retain water.

Most of the time high blood pressure goes back to normal after you deliver the baby. If your blood pressure stays high, your doctor may put you on medication.

Back to blog