Skip to content

2 September 2021

Blood Pressure Changes in Pregnancy

Low blood pressure is typical during pregnancy. Most of the time, this condition will not cause serious complications, and your blood pressure will recover to pre-pregnancy levels after you deliver your baby. Very low blood pressure, on the other hand, can be harmful to both mum and baby in some circumstances.

Pregnancy Test

How will my blood pressure change in pregnancy?

Your circulatory system grows rapidly when you’re carrying a baby, which can cause a decrease in blood pressure.

During the first 24 weeks of pregnancy, it’s typical for your blood pressure to drop.

 

How is my blood pressure measured?

A device called a sphygmomanometer will be used to take your blood pressure readings.

A stethoscope, arm cuff, pump, and dial are generally included, however, automated systems with sensors and a digital display are very prevalent nowadays.

When taking a blood pressure reading, it’s recommended to sit with your back supported and your legs uncrossed. To fit the cuff over your upper arm, you’ll need to roll up your sleeves or remove any long-sleeved clothes. While the test is being performed, try to relax and avoid chatting.

Once your blood pressure has been taken you will be given two numbers:

The systolic reading gives the pressure of your blood on your arteries as it travels around your body. An ideal systolic reading would be 120.

The diastolic reading is the lowest pressure on your arteries when your heart rests between beats. An ideal diastolic reading would be 80.

If you have these readings you can enter them into our blood pressure tool, as shown below the tool will place your readings on the chart.

Why is my blood pressure measured?

Blood pressure refers to the force with which your blood pushes against the sidewalls of your arteries as it circulates throughout your body.

Hypertension (high blood pressure) puts a burden on your arteries and organs, increasing your risk of catastrophic issues including heart attacks and strokes.

 

Although low blood pressure (hypotension) can induce dizziness and fainting in some people, it is typically not as dangerous.

Most doctor’s appointments include a blood pressure check. Blood pressure checks are a vital component of maintaining your overall health.

People over the age of 18 who have normal blood pressure and no risk factors for heart disease should get their blood pressure checked every two to five years.

Those aged 40 and above — or younger people with a higher risk of high blood pressure — should get their blood pressure checked once a year. Obesity and race are also risk factors for high blood pressure.

Blood pressure testing may be required more often in those with chronic health problems such as high or low blood pressure or heart disease.

Your doctor could also recommend that you check your blood pressure at home. Home blood pressure monitors that are automatic and simple to use and widely available, find a full list of our blood pressure monitors here. Consult your doctor to see whether this is a viable choice for you.

Keep a blood pressure diary at home and have your doctor double-check your monitor once a year to ensure you’re getting correct readings.

Blood pressure monitoring at home isn’t a replacement for doctor appointments.

Blood pressure tool

Tracking your blood pressure during pregnancy

If you’ve been taking blood pressure medication throughout your pregnancy, continue to do so throughout labour.

Your blood pressure should be checked hourly during labour if you have mild or moderate hypertension. You should be able to have a natural vaginal delivery as long as your blood pressure is within goal ranges.

Your blood pressure will be checked every 15 to 30 minutes throughout labour if you have severe hypertension. Your doctor may also suggest delivering your baby by forceps, ventouse, or caesarean section.

Your blood pressure will be checked after the birth.

If you had hypertension before becoming pregnant, you should have your medication reviewed two weeks after your baby is born.

 

Normal blood pressure levels during pregnancy

A pregnant woman’s blood pressure should also be within the safe range of less than 120/80 mm Hg, according to the American College of Obstetricians and Gynecologists (ACOG).

If you have high blood pressure when pregnant, it might mean you’re at risk for serious problems like preeclampsia.

Blood pressure should be monitored and managed during pregnancy.

 

How to detect abnormal blood pressure

Your doctor will do a physical examination and ask you questions about your medical history. A doctor, nurse, or other medical assistant will wrap an inflated arm cuff over your arm and use a pressure-measuring gauge to take your blood pressure.

Alternatively, you can buy an at home blood pressure monitor, and measure your blood pressure from the comfort of your own home.

There are numerous types of blood pressure measurements:

Blood pressure is in the normal range. If your blood pressure is less than 120/80 mm Hg, it is considered normal.

Blood pressure that is too high. A systolic pressure of 120 to 129 mm Hg and a diastolic pressure of less than (but not more than) 80 mm Hg are considered elevated blood pressure. Unless steps are taken to control blood pressure, elevated blood pressure tends to worsen over time. Prehypertension is another term for high blood pressure.

First stage hypertension – A systolic pressure of 130 to 139 mm Hg or a diastolic pressure of 80 to 89 mm Hg is considered stage 1 hypertension.

Hypertension in the second stage. A systolic pressure of 140 mm Hg or higher, or a diastolic pressure of 90 mm Hg or higher, is considered stage 2 hypertension.

A hypertensive emergency. A blood pressure reading of more than 180/120 mm Hg is a medical emergency that necessitates immediate medical attention. Wait five minutes and recheck if you receive this result when taking your blood pressure at home. If your blood pressure remains high, see your doctor right away. Call 999 or your local emergency medical number if you have chest pain, vision problems, numbness, or weakness, breathing difficulty, or any other signs and symptoms of a stroke or heart attack.

The importance of both values in a blood pressure measurement cannot be overstated. However, after the age of 50, the systolic reading becomes even more critical. Isolated systolic hypertension is characterised by a normal diastolic pressure (less than 80 mm Hg) but a high systolic pressure (greater than or equal to 130 mm Hg). This is a form of high blood pressure that is frequent in adults over the age of 65.

 

Because blood pressure varies throughout the day and can rise during a doctor visit (white coat hypertension), your doctor will most likely take several blood pressure readings over three or more appointments before diagnosing you with high blood pressure.

pregnancy

Causes of abnormal blood pressure during pregnancy

There are several possible causes of high blood pressure during pregnancy.

These include:

  • being overweight or obese
  • not getting enough physical activity
  • smoking
  • drinking alcohol
  • first-time pregnancy
  • a family history of pregnancy-related hypertension
  • carrying more than one child
  • age (over 35)
  • assistive reproductive technology (such as in vitro fertilization, or IVF)
  • having diabetes or certain autoimmune diseases

Treating abnormal blood pressure during pregnancy

Obesity and other common risk factors for high blood pressure can be reduced via diet and exercise.

It’s natural to gain weight during pregnancy. If you’re worried, talk to your doctor about a weight-gain goals and strategies to keep within a safe weight range.

Dietary recommendations for pregnant women differ from one person to the next. A nutritionist may assist you in developing a food plan that is tailored to your height and weight.

Avoid smoking and consuming alcoholic beverages. Both are known to increase blood pressure and induce other pregnancy problems.

Salt is essential during pregnancy, and limiting salt consumption is typically unnecessary, even for women with high blood pressure. Excessive salt restriction can damage pregnant women and have an influence on foetal growth and development.

Hormone changes, as well as psychological and physical changes, occur throughout pregnancy. This can cause tension, which makes it more difficult to control high blood pressure. Try stress-relieving exercises like yoga and meditation.

Medication for high blood pressure during pregnancy

Some traditional blood pressure medications can cause problems in pregnant women.

These medications for lowering blood pressure are typically not recommended during pregnancy:

  • ACE inhibitors
  • renin inhibitors
  • angiotensin receptor blockers

These drugs will pass through the bloodstream to the baby and negatively impact the developing baby’s health.

Methyldopa and labetalol are both drugs that are considered safe to use to manage blood pressure during pregnancy.

Complications of abnormal blood pressure during pregnancy

If high blood pressure is not managed during pregnancy, it can be fatal to both the mother and the foetus.

Hypertensive disorders caused by high blood pressure are the second-leading cause of maternal mortality in the United States during pregnancy, so any symptoms or concerns should be discussed with your doctor.

In general, diligent monitoring and some lifestyle modifications can reduce your risk of high blood pressure problems.

Preventing abnormal blood pressure during pregnancy

Keeping active and engaging in some form of physical exercise each day, such as walking or swimming, can help you maintain healthy blood pressure levels. Blood pressure can be lowered by eating a well-balanced diet and limiting salt consumption.

Learn about exercising during pregnancy, good nutrition throughout pregnancy, salt in the diet, and salt-reduction strategies.

There isn’t enough data to suggest that taking dietary supplements like magnesium, folic acid, or fish oils will help prevent high blood pressure.

Outlook for pregnant women with abnormal blood pressure

High blood pressure during pregnancy poses various risks, including:

Decreased blood flow to the placenta. If the placenta doesn’t get enough blood, your baby might receive less oxygen and fewer nutrients. This can lead to slow growth (intrauterine growth restriction), low birth weight or premature birth. Prematurity can lead to breathing problems, increased risk of infection and other complications for the baby.

Placental abruption. Preeclampsia increases your risk of this condition in which the placenta separates from the inner wall of your uterus before delivery. Severe abruption can cause heavy bleeding, which can be life-threatening for you and your baby.

Intrauterine growth restriction. Hypertension might result in slowed or decreased growth of your baby (intrauterine growth restriction).

Injury to your other organs. Poorly controlled hypertension can result in injury to your brain, heart, lungs, kidneys, liver and other major organs. In severe cases, it can be life-threatening.

Premature delivery. Sometimes an early delivery is needed to prevent potentially life-threatening complications when you have high blood pressure during pregnancy.

Future cardiovascular disease. Having preeclampsia might increase your risk of future heart and blood vessel (cardiovascular) disease. Your risk of future cardiovascular disease is higher if you’ve had preeclampsia more than once or you’ve had a premature birth due to having high blood pressure during pregnancy.

pregnancy outlook

What should I do if I have high blood pressure before, during, or after pregnancy?

Before Pregnancy

Schedule a preconception check-up with the health care physician who will be handling your pregnancy if you have high blood pressure. Other members of your health-care team, such as your family doctor or cardiologist, should also be consulted. They’ll assess how effectively you’re managing your high blood pressure and discuss any treatment adjustments you might need to make before becoming pregnant.

If you’re overweight, your health care physician may advise you to lose weight before trying to conceive.

During Pregnancy

Blood pressure monitoring is a crucial aspect of prenatal care. If you have persistent hypertension, your doctor will take your blood pressure in one of the following categories:

Blood pressure that is too high. A systolic pressure of 120 to 129 millimetres of mercury (mm Hg) and a diastolic pressure of less than 80 mm Hg is considered elevated blood pressure. Unless efforts are made to manage blood pressure, elevated blood pressure tends to worsen with time.

Hypertension in the first stage. A systolic pressure of 130 to 139 mm Hg or a diastolic pressure of 80 to 89 mm Hg is considered stage 1 hypertension.

Hypertension in the second stage. A systolic pressure of 140 mm Hg or higher, or a diastolic pressure of 90 mm Hg or higher, indicates stage 2 hypertension.

Gestational hypertension is defined as blood pressure that exceeds 140/90 mm Hg after 20 weeks of pregnancy and is documented on two or more times, at least four hours apart, without any other organ damage.

After Pregnancy

Postpartum preeclampsia is a condition that can happen after childbirth. This rare condition will cause the woman to have high blood pressure and high levels of protein in her urine. This is a serious condition that can lead to brain damage, stroke, HELLP syndrome and death if not treated.

What are the different types of high blood pressure?

Chronic Hypertension

Hypertension, or high blood pressure, raises the risk of coronary heart disease (heart attack) and stroke (brain attack). High blood pressure causes the arteries to become more resistant to blood flow, requiring the heart to work harder to circulate the blood. High blood pressure usually has no warning signs or symptoms. You can find out whether your blood pressure is high by getting it tested by your doctor on a regular basis.

Gestational Hypertension

Gestational hypertension is high blood pressure in pregnancy. It occurs in about 3 in 50 pregnancies.

This condition is different from chronic hypertension. Chronic hypertension happens when a woman has high blood pressure before she gets pregnant. It’s also different from preeclampsia and eclampsia.

This issue often starts in the second half of pregnancy. It normally goes away after your baby is born.

cause high blood pressure

What causes high blood pressure?

Food, medicine, lifestyle, age, and genetics can cause high blood pressure. Your doctor can help you find out what might be causing yours. Common factors that can lead to high blood pressure include:

  • A diet high in salt, fat, and/or cholesterol.
  • Chronic conditions such as kidney and hormone problems, diabetes, and high cholesterol.
  • Family history, especially if your parents or other close relatives have high blood pressure.
  • Lack of physical activity.
  • Older age (the older you are, the more likely you are to have high blood pressure).
  • Being overweight or obese.
  • Race (non-Hispanic black people are more likely to have high blood pressure than people of other races).
  • Some birth control medicines and other medicines.
  • Tobacco use or drinking too much alcohol.

Symptoms of high blood pressure (hypertension)

High blood pressure rarely has noticeable symptoms. The following can be symptoms of high blood pressure:

  • Blurred vision
  • Nosebleeds
  • Shortness of breath
  • Chest pain
  • Dizziness
  • Headaches

More than 1 in 4 adults in the UK have high blood pressure but many will not know they have it. Many people with high blood pressure feel fine. But even if you feel fine, you should still have your blood pressure checked regularly. If you’re a healthy adult over 40, it’s recommended that you get it checked at least once every five years. But if you’re at increased risk of high blood pressure, you should have it checked more often, ideally once a year.

What’s considered a high blood pressure level during pregnancy?

There are 3 levels of hypertension (these are the same for pregnant women):

mild – blood pressure between 140/90 and 149/99mmHg (millimetres of mercury); may be checked regularly but does not usually need treatment

moderate – blood pressure between 150/100 and 159/109mmHg

severe – blood pressure of 160/110mmHg or higher

Dangers of high blood pressure during pregnancy

Preeclampsia

Who is at risk for preeclampsia?

You are more at risk for preeclampsia if:

  • You are giving birth for the first time.
  • You have a history of preeclampsia from a prior pregnancy.
  • You have high blood pressure that has been present for a long time, or you have chronic renal disease, or both.
  • You’ve had thrombophilia before (a condition that increases risk of blood clots).
  • You’re expecting numerous children (such as twins or triplets).
  • You used in vitro fertilisation to get pregnant.
  • You have a history of preeclampsia in your family.
  • You have diabetes, either type 1 or type 2.
  • You’re overweight.
  • You’ve been diagnosed with lupus (an autoimmune disease).
  • You are over the age of 40.

What causes preeclampsia?

Preeclampsia can occur after you’ve given birth in rare circumstances. Postpartum preeclampsia is a severe medical disease that occurs after a woman gives birth. It can happen to women who have never had preeclampsia throughout their pregnancy.  Postpartum preeclampsia shares many of the same symptoms as preeclampsiaexternal. Preeclampsia after birth is usually identified within 48 hours, although it can occur up to 6 weeks later. 

What are the symptoms of preeclampsia?

Symptoms of preeclampsia include:

  • A headache that will not go away
  • Changes in vision, including blurry vision, seeing spots, or having changes in eyesight
  • Pain in the upper stomach area
  • Nausea or vomiting
  • Swelling of the face or hands
  • Sudden weight gain
  • Trouble breathing

Some women have no symptoms of preeclampsia, which is why it is important to visit your health care team regularly, especially during pregnancy.

How is preeclampsia diagnosed?

Pre-eclampsia is easily diagnosed during the routine checks you have while you’re pregnant.

During these antenatal appointments, your blood pressure is regularly checked for signs of high blood pressure and a urine sample is tested to see if it contains protein.

If you notice any of the symptoms of pre-eclampsia between your antenatal appointments, see your midwife or GP for advice.

What are the treatments for preeclampsia?

Pre-eclampsia can only be cured by delivering the baby. If you have pre-eclampsia, you’ll be closely monitored until it’s possible to deliver the baby.

Once diagnosed, you’ll be referred to a hospital specialist for further assessment and any necessary treatment.

If you only have high blood pressure without any signs of pre-eclampsia, you can usually return home afterwards and attend regular (possibly daily) follow-up appointments.

If pre-eclampsia is confirmed, you’ll usually need to stay in hospital until your baby can be delivered.

Eclampsia

Eclampsia is a serious preeclampsia consequence. High blood pressure causes seizures during pregnancy, which is an uncommon but dangerous disease.

Seizures are moments of abnormal brain activity that can result in staring, drowsiness, and convulsions (violent shaking). Eclampsia affects around one out of every 200 women who have preeclampsia. Even if you don’t have a history of seizures, you can develop eclampsia.

What should I do if I have low blood pressure before, during, or after pregnancy?

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.

During pregnancy

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

After pregnancy

After you give delivery, your blood pressure should recover to pre-pregnancy levels.

In the hours and days following your baby’s birth, medical personnel will check your blood pressure often. Additionally, during your postnatal office visits, your doctor will most likely check your blood pressure.

beach

What are the different types of low blood pressure?

Postural hypotension

When a person stands up after sitting or lying down, their blood pressure drops unnaturally. This is known as postural hypotension. Although not everyone with this disease experiences symptoms, it can cause dizziness, light-headedness, fainting, and even falls.

Postural hypotension is more frequent in the elderly and in persons with diseases like Parkinson’s disease or diabetes that impair the portion of the nervous system that regulates blood pressure. People can potentially develop the disease if they are dehydrated or using certain medications (for example, to treat high blood pressure).

Postprandial hypotension

Following a meal, postprandial hypotension refers to a rapid drop in blood pressure. Dizziness, light-headedness, and falls are all possible side effects. To diagnose postprandial hypertension, doctors take blood pressure before and after a meal. Eating short, low-carbohydrate meals on a regular basis may be beneficial.

Neurally mediated hypotension

NMH (neurally mediated hypotension) is a blood pressure regulation disorder that occurs while a person is standing up. NNH causes a drop of 20–25 mm Hg in systolic blood pressure when a person is standing still compared to lying down. NMH is a kind of orthostatic intolerance.

Orthostatic hypotension

Orthostatic hypotension is a type of low blood pressure caused by the failure of blood vessels to contract while the body stands upright. It’s more often a sign of an underlying illness than a sickness in and of itself. Orthostatic hypotension becomes more common as people age.

Symptoms of low blood pressure (hypotension)

For some people, low blood pressure signals an underlying problem, especially when it drops suddenly or is accompanied by signs and symptoms such as:

  • Dizziness or light-headedness
  • Fainting
  • Blurred or fading vision
  • Nausea
  • Fatigue
  • Lack of concentration
pregnancy sitting

What’s considered a low blood pressure level during pregnancy?

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.

Effects of pregnancy on blood pressure

Due to the fast expansion of the vascular system during pregnancy, blood pressure is likely to decrease. This is normal, and once you’ve given birth, your blood pressure should recover to its pre-pregnancy level.

Does blood pressure affect the baby?

High blood pressure during pregnancy poses various risks, including: Decreased blood flow to the placenta. If the placenta doesn’t get enough blood, your baby might receive less oxygen and fewer nutrients. This can lead to slow growth (intrauterine growth restriction), low birth weight or premature birth.

Postpartum blood pressure

Postpartum preeclampsia is high blood pressure in a woman who has recently had a baby. It can happen as early as a few days afterwards, or up to several weeks after having a baby. In addition to high blood pressure, a woman who has postpartum preeclampsia will also have too much protein in her urine.

Related products

    • Easy to use
    • 90 results memory
    • WHO classification indicator
    • Irregular heartbeat detection
    Buy nowAdd to basket

    • Easy to use
    • 3 users x 60 results memory
    • Irregular heartbeat detection
    • Advanced BP alert reminders
    • Average readings as BIHS guidelines
    Buy nowAdd to basket

    • Easy to use
    • 2 users x 60 results memory
    • Irregular heartbeat detection
    • Averages last three readings
    Buy nowAdd to basket

14 September 2021

High blood pressure and fainting

 

10 September 2021

Blood Pressure Numbers Explained

 

9 September 2021

5 exercises to normalise blood pressure

 

1 September 2021

How to Naturally Lower Blood Pressure

What is blood pressure? Blood pressure is the pressure that you are circulating on the walls of your arteries...