Hyperemesis gravidarum (HG) is a severe form of nausea and vomiting during pregnancy. It can cause dehydration, weight loss, and electrolyte imbalances and can be debilitating.

It’s common to experience morning sickness (nausea) during pregnancy. This condition is generally harmless. While morning sickness can be quite uncomfortable, it typically goes away within 12 weeks.

Hyperemesis gravidarum (HG) is an extreme form of morning sickness that causes severe nausea and vomiting during pregnancy. It often requires hospital treatment.

Morning sickness and HG are very different conditions. They have different complications and side effects. It’s important to distinguish between these two conditions to properly treat symptoms.

Morning sickness

Morning sickness typically includes nausea that’s sometimes accompanied by vomiting. Nausea is common in pregnancy. Up to 90% of pregnant women experience it.

With morning sickness, nausea and vomiting usually disappear after 12 weeks of pregnancy but sometimes continue until 20 weeks or longer. The vomiting doesn’t cause severe dehydration.

Morning sickness typically begins in the first month of pregnancy. It usually goes away by the third or fourth month. People with morning sickness can get fatigue and a slight loss of appetite. They may have difficulty performing their usual daily activities.

Hyperemesis gravidarum

HG is a rarer condition, happening in only about 0.5% to 2% of pregnancies. It typically includes nausea that doesn’t go away and severe vomiting that leads to dehydration. This doesn’t allow you to keep any food or fluids down.

The symptoms of HG typically begin within the first 6 weeks of pregnancy. HG can be extremely debilitating and cause fatigue that lasts for weeks or months. People with HG may not be able to work or perform their normal daily activities.

HG can lead to dehydration and poor weight gain during pregnancy. There’s no known way to prevent morning sickness or HG, but there are ways to manage the symptoms.

HG usually starts during the first trimester of pregnancy. Symptoms can come and go, so there may be times when you need hospital treatment to manage your symptoms, and other times when you feel better.

Some of the most common symptoms of HG are:

  • feeling nearly constant nausea
  • losing your appetite
  • vomiting frequently
  • becoming dehydrated
  • feeling lightheaded or dizzy
  • losing more than 5% of your body weight due to nausea or vomiting

Almost all pregnant people experience some degree of morning sickness. Morning sickness is nausea and vomiting during pregnancy. Despite the name, morning sickness isn’t confined to the morning. It can occur at any time.

Morning sickness and HG seem to have a connection to human chorionic gonadotropin (hCG). This is a hormone created during pregnancy by the placenta. Your body produces a large amount of this hormone at a rapid rate early in pregnancy. These levels typically peak about 10 to 12 weeks into your pregnancy and then begin to decline.

Some factors that could increase your risk of getting HG are:

  • having a history of HG in your family
  • having a multiple pregnancy, such as twins or triplets
  • being pregnant for the first time

Trophoblastic disease can also cause HG. Trophoblastic disease occurs when there’s an abnormal growth of cells inside the uterus.

Your doctor will ask you about your medical history and your symptoms. A standard physical exam is enough to diagnose most cases. Your doctor will look for common signs of HG, such as abnormally low blood pressure or a fast pulse.

Blood and urine samples may also be necessary to check for signs of dehydration. Your doctor might also order additional tests to rule out gastrointestinal problems as a cause of your nausea or vomiting.

An ultrasound might be necessary to find out whether you’re pregnant with twins or whether there are any problems. This test uses sound waves to create an image of the inside of your body.

Treatment for HG depends on the severity of your symptoms.

Sometimes, early treatment of morning sickness may lower your risk of developing HG. Your doctor may recommend natural nausea prevention methods, such as vitamin B6 or ginger.

Morning sickness may also be treated by eating smaller, more frequent meals and dry foods, such as crackers. Drink plenty of fluids to stay hydrated.

Unlike typical morning sickness, HG requires medical treatment.

Usually, a person experiencing HG will need to be treated in a hospital. If you’re unable to keep fluids or food down due to constant nausea or vomiting, you’ll need to get them intravenously (through an IV).

Medication is necessary when vomiting puts your health or the health of the fetus (baby) at risk. Some of the most commonly used anti-nausea drugs are promethazine and meclizine. These medications can be taken in different ways. For example, promethazine can be taken as an injection, suppository, oral medication, or topical treatment.

Some of the medications that can be used to treat severe HG, like methylprednisolone, can cause birth defects. However, severe dehydration and other complications of HG may be of greater concern.

Talk with your doctor about the risks associated with any method of treatment.

The good news is that symptoms of HG will disappear after giving birth. And treating HG during pregnancy can help reduce the risk of complications for you and the baby.

Talk with your doctor, and pursue education and support groups to help you and your family deal with HG. Be sure to communicate your feelings to your doctor and personal support system.