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Hyperemesis Gravidarum


Antonette T. Dulay

, MD, Main Line Health System

Reviewed/Revised Oct 2022

Hyperemesis gravidarum is extremely severe nausea and excessive vomiting during pregnancy.

  • Women with hyperemesis gravidarum, unlike women with ordinary morning sickness, lose weight and become dehydrated.

  • Doctors diagnosis hyperemesis gravidarum based on symptoms and do tests to check for dehydration and other possible causes of the vomiting.

  • Treatment involves nothing by mouth at first, fluids containing electrolytes and vitamins given by vein, and drugs to relieve the nausea, and rarely, giving all food intravenously.

Pregnancy complications, such as hyperemesis gravidarum, are problems that occur only during pregnancy. They may affect the woman, the fetus, or both and may occur at different times during the pregnancy. However, most pregnancy complications can be effectively treated.

Pregnancy frequently causes nausea and vomiting. It usually occurs in the morning (as so-called morning sickness Nausea and Vomiting During Early Pregnancy Pregnancy frequently causes nausea and vomiting. It is often called "morning sickness," but it can occur any time of day or night. This type of nausea and vomiting usually starts around 5 weeks... read more ), although it can occur any time of day. This type of nausea and vomiting usually starts around 5 weeks of pregnancy and is at its worst at about 9 weeks. It disappears by about 16 to 18 weeks.

Hyperemesis gravidarum differs from typical morning sickness. If women vomit often and have nausea to such an extent that they lose weight and become dehydrated, they have hyperemesis gravidarum. If women vomit occasionally but gain weight and are not dehydrated, they do not have hyperemesis gravidarum.

The cause of hyperemesis gravidarum is unknown.

Symptoms of Hyperemesis Gravidarum

Women with hyperemesis gravidarum may not consume enough food to provide their body with energy. Then the body breaks down fats, resulting in a buildup of waste products (ketones) called ketosis. Ketosis can cause fatigue, bad breath, dizziness, and other symptoms.

Rarely, hyperemesis gravidarum continues after 16 to 18 weeks of pregnancy. If it does, the following may occur:

Diagnosis of Hyperemesis Gravidarum

  • Sometimes regular measurements of weight

  • Blood and urine tests

Doctors ask women about the vomiting:

  • When it started

  • How long it lasts

  • How many times a day it occurs

  • Whether anything relieves or makes it worse

  • What the vomit looks like

  • How much vomit there is

Doctors suspect hyperemesis gravidarum based on symptoms. Regularly measuring the woman's weight can help support the diagnosis of hyperemesis gravidarum. If doctors suspect this disorder, they do blood and urine tests to determine whether dehydration is present and to check for electrolyte abnormalities, which may result from dehydration.

Other tests may be done to rule out other possible causes of vomiting.

Treatment of Hyperemesis Gravidarum

  • Nothing by mouth at first

  • Fluids given intravenously

  • Drugs to relieve nausea

  • Rarely, intravenous feeding

If hyperemesis gravidarum is confirmed, the woman is given nothing by mouth at first. Instead, she is given fluids intravenously. The fluids usually contain sugar (glucose) and include electrolytes and vitamins as needed. If vomiting is severe and persists, the woman is hospitalized and continues to be given fluids containing any needed supplements. She is also given drugs to relieve nausea (antiemetics) by mouth, injection, or suppository.

After the woman is rehydrated and vomiting has subsided, she is given fluids to drink. If she can tolerate fluids, she can begin eating frequent, small portions of bland foods. The size of the portions is increased as she can tolerate more food. If she cannot drink fluids, she may need to be given fluids intravenously in the hospital or at home for a longer period of time.

If symptoms recur, the treatment is repeated.

Rarely, if weight loss continues and symptoms persist despite treatment, corticosteroids (such as methylprednisolone) may be used for a short time. However, they are rarely used during the 1st trimester because they can cause birth defects.

If vomiting continues despite treatment and causes continuing weight loss, jaundice, and abnormal heart rhythms in the mother, the mother's life may be in danger. In such cases, ending the pregnancy may be an option. Women can discuss this option with their doctor.

Drugs Mentioned In This Article

Generic Name Select Brand Names
A-Methapred, Depmedalone-40, Depmedalone-80 , Depo-Medrol, Medrol, Medrol Dosepak, Solu-Medrol
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