When someone is pregnant, they may experience hypoglycemia, or low blood sugar, due to changes in how their body regulates and metabolizes glucose.

Hypoglycemia is when someone has low blood sugar. Low blood sugar can cause difficulty thinking or concentrating and may cause fainting.

People who notice symptoms of hypoglycemia while they are pregnant should speak with a doctor about testing for diabetes, which is the most common cause of pregnancy-related hypoglycemia.

In this article, we take a close look at hypoglycemia during pregnancy, including the causes, symptoms, risks, and how hypoglycemia may affect the baby.

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People with diabetes are especially vulnerable to hypoglycemia when pregnant, particularly those with type 1 diabetes. A 2021 article suggests it affects between 36% and 71% of pregnant people who take insulin.

Insulin is a hormone that helps to control the body’s blood sugar levels. During pregnancy, a person’s body requires more insulin because the placenta produces extra blood sugar.

This, along with hormonal changes during pregnancy, can make it difficult for a person’s body to regulate glucose. When the body cannot produce enough insulin, a pregnant person who did not previously have diabetes may develop gestational diabetes.

People also tend toTrusted Source become more insulin resistant as their pregnancy continues, which means that the body responds less well to insulin.

As a result of these factors, it is more likely that a pregnant person will develop hyperglycemia, which is high blood sugar. However, people may also develop low blood sugar or alternate between the two conditions.

A person’s body has difficulty fueling itself when it has low blood glucose. The result can be weakness, confusion, and other symptoms that someone might expect after missing a meal or two.

Other symptoms may include:

When someone has severeTrusted Source hypoglycemia, they may experience more serious symptoms, such as seizures, convulsions, or a loss of consciousness. This requires immediate treatment.

Anyone with symptoms of hypoglycemia during pregnancy should talk with their doctor to find out the cause. Two types of hypoglycemia can occur during pregnancy:

  • Reactive hypoglycemia: This happens when blood sugar levels drop within a few hours of a meal.
  • Fasting hypoglycemia: This occurs when blood sugar drops dangerously low between meals.

The causes of low blood sugar during pregnancy include:

Diabetes

Diabetes is a common cause of hypoglycemia during pregnancy. However, hyperglycemia is more common than hypoglycemia during pregnancy, but both can occur at different stages of pregnancy.

High blood sugar levels can occur with type 1 diabetes, where the body is unable to produce correct levels of insulin, and type 2 diabetes, where the body is insulin resistant.

Low blood sugar levels can occurTrusted Source when a person takes too much insulin or does not eat enough carbohydrates.

Occasionally, hormonal and other changes during pregnancy may cause people with diabetes to develop hypoglycemia even without medication. So, it is crucial for people with diabetes to carefully monitor their blood sugar throughout their pregnancy.

Gestational diabetes

Some people develop gestational diabetes during pregnancy. This condition can occurTrusted Source due to insulin resistance, hormonal changes, and the increased demands of pregnancy on the body.

Gestational diabetes can also cause low blood sugar.

According to the American Diabetes Association, around 9.2% of pregnancies in the United States involve gestational diabetes every year. This condition usually goes away after the baby is born.

Morning sickness

Blood sugar can become very low in people who do not eat enough carbohydrates.

People with severe morning sickness may develop low blood sugar if they frequently vomit. People with morning sickness who vomit daily, do not gain weight, or feel light-headed should consult their doctor.

Lifestyle factors

Several lifestyle factors may contribute to hypoglycemia in pregnancy, particularly in people with another risk factor, such as diabetes.

Lifestyle factors that may increase the risk of hypoglycemia include:

  • not eating enough or missing meals
  • exercising more than usual
  • drinking alcohol

Medication

Diabetes drugs, such as insulin, can lower blood sugar levels. When someone does not eat enough carbohydrates or takes too much insulin, they may develop dangerously low blood sugar.

Some other medications may also lower blood sugar, including:

People should discuss any medications they take with a doctor after getting pregnant.

Rare medical disorders

Several rare conditions can cause hypoglycemia. These conditions may affect a developing baby, so it is essential to get an accurate diagnosis and treatment.

Disorders that can cause hypoglycemia includeTrusted Source:

Mild hypoglycemia may not harm a developing baby. A doctor may recommend eating more or adjusting medication. However, regular hypoglycemia during pregnancy may harm a developing baby.

People who have severe hypoglycemia may need hospitalization or monitoring.

People with gestational diabetes may give birth to unusually large babies. This can make a vaginal delivery more difficult and may increase the risk of injury to mother and baby.

Babies born to mothers with diabetes may also have jaundice, and their blood sugar may drop dangerously low shortly after birth. They may need monitoring during and after delivery.

Most doctors test for gestational diabetes between the 24th and 28th weeksTrusted Source of pregnancy. People who show signs of diabetes before or after this may need additional testing.

If someone does not have diabetes, a doctor may perform additional blood work to find the cause of hypoglycemia. A complete medical history and information about lifestyle can help with a proper diagnosis.

Treatment for diabetes during pregnancy may be different from usual diabetes management. People will need toTrusted Source check their blood sugar regularly. They may also need to change their diet and exercise more, which can also help balance blood sugar.

If these strategies fail, people may need to take insulin or other medications. As some diabetes medications can cause hypoglycemia, people must follow their doctor’s instructions carefully.

If another condition is causing the hypoglycemia, treatment will depend on the cause. For instance, someone with a tumor that causes a hormonal imbalance may need to have it removed, either during or after the pregnancy.

The most significant complications related to hypoglycemia in pregnancy are due to diabetes. A pregnant person with diabetes can haveTrusted Source complications, such as preeclampsia, and their babies may need additional monitoring.

Untreated hypoglycemia can lead to severe complications, includingTrusted Source:

  • seizures
  • brain damage
  • death

Most people with gestational diabetes improve after pregnancy but may experience the condition with subsequent pregnancies. Gestational diabetes is also a risk factor for type 2 diabetes.

People with type 1 or type 2 diabetes will need to continue managing their diabetes after their pregnancy.

Whatever the cause of hypoglycemia during pregnancy, careful monitoring of the parent and baby can reduce the risk of serious complications.

Hypoglycemia during pregnancy can happen for many reasons, including when someone skips a meal. It is essential to get a proper diagnosis because hypoglycemia and diabetes can have adverse effects on labor and delivery.

However, proper medical care and management of blood sugar levels can help keep the parent and baby safe.