How to prevent passing out while pregnant

Table of Contents Show

Relaxed blood vessels
Vasovagal syncope
Morning sickness
Insulin resistance
More serious health issues

Medically reviewed by Debra Rose Wilson, Ph.D., MSN, R.N., IBCLC, AHN-BC, CHT — Written by Zawn Villines on March 20, 2020

Is it normal?
Causes
Prevention
Treatment
Risks
Seeing a doctor
Summary

Dizziness is one of the most common pregnancy symptoms. It is not usually a cause for concern, but for some women, it can be severe.

Dizziness affects many women during pregnancy, and it is often more of an annoyance than a sign of a severe problem.

Still, it is important to consult a healthcare professional about any dizziness, especially if it is severe, causes fainting, or makes it difficult to work or do other daily activities.

The authors of a 2019 study pointed out that fainting is also common among pregnant women.

They concluded that fainting — especially when it occurs during the first trimester — increases the risk of pregnancy complications, such as preterm birth and congenital abnormalities, as well as cardiac problems for the woman later on.

Share on PinterestDilated blood vessels are a possible cause of dizziness during pregnancy.

Early in pregnancy, an increase in hormones leads to the dilation of blood vessels, which may cause lightheadedness. This symptom may improve or worsen as the pregnancy progresses.

Specifically, an increase in the pregnancy hormone human chorionic gonadotropin may cause dizziness, as well as nausea, that usually gets better by the end of the first trimester.

However, as the pregnancy progresses, and the growing uterus crowds other organs, some women find that dizziness gets worse. They may feel lightheaded or have trouble breathing, especially when it is hot outside or during moments of exertion.

Changes in blood sugar levels may also cause dizziness throughout pregnancy. Early in pregnancy, some women find that when their blood sugar is low, or they are hungry, they feel dizzy, shaky, or nauseous.

Toward the end of the second trimester, the body struggles to make and use insulin. This issue can cause gestational diabetes, which may make some women feel dizzy.

Dizziness has many causes, including hormonal shifts, hunger, and problems with the heart or blood vessels. The most common causes during pregnancy include:

Relaxed blood vessels

During pregnancy, the body produces hormones, including one called relaxin, which causes blood vessels to dilate. This dilation increases the blood flow to the developing baby.

However, the increase in blood flow also slows the return of blood to the woman’s head, and this can cause dizziness during exertion or even when standing up quickly.

Vasovagal syncope

Vasovagal syncope causes dizziness and fainting when the body, even very briefly, does not regulate blood pressure. It happens when blood pressure suddenly drops — often in response to anxiety or stress.

Some women experience this for the first time during pregnancy, due to the added stress that it places on the body. For example, a woman with a needle phobia may become dizzy when undergoing routine blood testing during pregnancy. Vasovagal syncope is not usually a sign that anything is wrong, but it sometimes indicates an irregular heart rhythm. A murmur in pregnancy is not uncommon because of the increased amount of fluids.

Anyone who experiences this symptom should inform a doctor, even if it resolves without treatment.

Hunger

Some women notice an increase in dizziness when they are hungry.

During the second and third trimesters of pregnancy, women need more calories to sustain their body and the fetus, which can lead to more frequent hunger. As blood glucose drops, dizziness may increase.

Morning sickness

Morning sickness tends to involve nausea, vomiting, headaches, or a combination of these symptoms, but some women also become dizzy. It can also affect women at different times of the day.

In some cases, morning sickness gets worse when a woman is hungry or tired. Symptoms usually become progressively more intense during the first trimester and resolve by the end of the first or second trimester.

Women with intense morning sickness who vomit regularly may have hyperemesis gravidarum. This condition can cause dehydration and pregnancy complications, and it often lasts for the entire pregnancy.

Anyone who experiences frequent vomiting or any weight loss should consult a doctor.

Insulin resistance

Insulin helps the body digest glucose and turn it into energy.

Even during a healthy pregnancy, the body cannot use insulin as effectively as it would at other times, and this causes mild insulin resistance. In some women, however, it leads to gestational diabetes.

Some women with gestational diabetes experience dizziness when they are hungry, when their blood sugar is too high, or when diabetes medication causes their blood sugar to plummet.

Exertion

Late in pregnancy, as the uterus expands, it puts pressure on many organs, including the lungs. This pressure can make it difficult for the lungs to expand fully when a woman breathes.

While breathing may become more difficult, the body demands more oxygen during pregnancy. Therefore, pregnant women may feel dizzy when they exercise, breathe heavily, or get too hot.

More serious health issues

Although dizziness is not an unexpected issue during pregnancy, in some women, it signals a more serious problem, such as high blood pressure, an infection, or a blood clot.

Anyone who experiences sudden, intense dizziness should call a healthcare professional.

Pregnant women can reduce the risk of dizziness by:

Standing up slowly: Women who experience vasovagal syncope may be able to prevent sudden blood pressure drops by tightening the muscles in their legs.
Exercising with care: While exercise is key for keeping the body, and particularly the heart, healthy during pregnancy, it is important to go slowly and increase the intensity only on the advice of a doctor.
Eating small meals throughout the day: Some women find that foods rich in protein and other nutrients, such as eggs, are especially helpful.
Drinking plenty of water: Helping prevent dizziness is just one of the many benefits of hydration.
Keeping stress and anxiety at bay: Receiving support from loved ones, attending to mental health, and practicing deep breathing exercises can all help.
Lying on the left side of the body: Lying on the left side keeps the expanded uterus from putting pressure on the liver and improves blood flow to the developing baby.

The approach to treating dizziness during pregnancy varies depending on the cause. Serious heart health problems, for example, will require treatment and monitoring in a hospital.

In most other cases, a doctor will monitor symptoms and recommend at-home treatments. Some options include:

vitamin B-6 and doxylamine (Unisom) for morning sickness
antinausea drugs
lifestyle and dietary changes to manage low blood sugar
insulin or other medications for gestational diabetes
antibiotics, if dizziness results from a bacterial infection

For the majority of pregnant women, the most dangerous complication of dizziness is falling and sustaining an injury.

Dizziness can also make driving, heavy lifting, and some other tasks dangerous. A doctor can offer advice on strategies to manage dizziness and whether it is safe to continue driving.

When a serious underlying health issue causes dizziness, it increases the risk of injury to both the woman and baby. The woman may go into early labor, develop high blood pressure, or experience other cardiac health problems, some of which can be life threatening, such as a pulmonary embolism.

For this reason, consulting a doctor about any dizziness is crucial.

Dizziness is a common issue during pregnancy and often no cause for alarm. However, as it increases the risk of injury to the woman and baby, it is important to contact a healthcare professional and discuss the potential causes.

If dizziness lasts more than a few moments, it is best to call a doctor or midwife immediately for guidance. It is better to “overreact” and receive any necessary care than to delay medical attention.

Anyone who experiences any of the following should receive emergency medical care:

severe shortness of breath
seizures
dizziness and a fever
any signs of premature labor, such as contractions, water breaking, or fluid coming from the vagina

Pregnancy can cause a host of discomforting symptoms. For many women, dizziness is just one of them, and it is not a sign of a serious problem.However, every symptom offers potentially important information about the health of the woman and baby.

In some cases, dizziness can point to an underlying problem, so it is crucial to keep a doctor informed about this symptom and any other health issues that arise.

Last medically reviewed on March 20, 2020