Low blood pressure during pregnancy is common and not usually a cause for concern. However, sometimes low blood pressure can be dangerous for you and your baby.

Having low blood pressure during pregnancy is common. Most of the time, this condition won’t cause major problems, and blood pressure will return to prepregnancy levels after you give birth. In some cases, however, very low blood pressure can be dangerous for mom and baby.

Effects of pregnancy on blood pressure

If you’re pregnant, your doctor or nurse will likely check your blood pressure at every prenatal visit.

Blood pressure is the force of your blood as it pushes against artery walls while your heart pumps. It can go up or down at certain times of the day, and it may change if you’re feeling excited or nervous.

Your blood pressure reading reveals important information about the health of you and your baby. It can also be a way for your doctor to determine if you have another condition that needs to be checked out, like preeclampsia.

Changes that happen in your body during pregnancy can affect your blood pressure. When carrying a baby, your circulatory system expands quickly, which may cause a drop in blood pressure.

It’s common for your blood pressure to lower in the first 24 weeks of pregnancy.

Other factors that can contribute to low blood pressure include:

  • dehydration
  • anemia
  • internal bleeding
  • prolonged bed rest
  • certain medications
  • heart conditions
  • endocrine disorders
  • kidney disorders
  • infections
  • nutritional deficiencies
  • allergic reaction

What’s considered low?

Current guidelines define a normal blood pressure reading as less than 120 mm Hg systolic (the top number) over 80 mm Hg diastolic (the bottom number).

Doctors typically determine you have low blood pressure if your reading is below 90/60 mm Hg.

Some people have low blood pressure their whole lives and have no signs of it.

Dangers of low blood pressure during pregnancy

Generally, low blood pressure during pregnancy isn’t a cause for concern unless you experience symptoms. Big drops may be the sign of a serious, or even life-threatening, problem.

Extremely low blood pressure can lead to falls, organ damage, or shock.

Low blood pressure may also be a sign of ectopic pregnancy, which happens when a fertilized egg implants outside of a woman’s uterus.

Does blood pressure affect the baby?

A large amount of research has been conducted on how high blood pressure during pregnancy affects babies, but data on the effects of low blood pressure is limited.

Some studies have suggested that low blood pressure during pregnancy may lead to problems, such as stillbirth and low birth weight. However, other research has shown additional risk factors are to blame for these outcomes.

More research is needed to understand the impact of low prenatal blood pressure on the health of a baby.

Symptoms of low blood pressure

Signs and symptoms of low blood pressure may include:

  • dizziness
  • lightheadedness, especially when standing or sitting up
  • fainting
  • nausea
  • tiredness
  • blurred vision
  • unusual thirst
  • clammy, pale, or cold skin
  • rapid or shallow breathing
  • lack of concentration

Call your healthcare provider if you develop any symptoms of low blood pressure during pregnancy.

Diagnosis

Low blood pressure is diagnosed with a simple test.

Your doctor or nurse will place an inflatable cuff around your arm and use a pressure-measuring gauge to calculate your blood pressure.

This test can be performed in your doctor’s office, but you can also buy your own device and measure your blood pressure at home.

If you have low blood pressure throughout your pregnancy, your doctor might order more tests to rule out other conditions.

Treatment

Generally, you won’t require treatment for low blood pressure during pregnancy.

Doctors typically don’t recommend medications for pregnant women unless symptoms are serious or complications are likely.

Your blood pressure will probably start to rise on its own during your third trimester.

Self-care for low blood pressure during pregnancy

If you do experience symptoms of low blood pressure, such as dizziness, you might want to try the following:

  • Avoid getting up quickly when you’re seated or lying down.
  • Don’t stand for long periods of time.
  • Eat small meals throughout the day.
  • Don’t take very hot baths or showers.
  • Drink more water.
  • Wear loose clothing.

It’s also a good idea to eat a healthy diet and take your prenatal supplements during your pregnancy to prevent symptoms of low blood pressure.

Postpartum blood pressure

Your blood pressure should return to your pre-pregnancy levels after you give birth.

Medical professionals will check your blood pressure often in the hours and days after you deliver your baby. Also, your doctor will probably check your blood pressure at your postnatal office visits.

Outlook

Low blood pressure during pregnancy is normal. The condition usually isn’t something to be concerned about unless you have symptoms.

If you do experience bothersome symptoms of low blood pressure, let your doctor know.

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