MSD Manual

Please confirm that you are not located inside the Russian Federation


Hyperemesis Gravidarum


Antonette T. Dulay

, MD, Main Line Health System

Last full review/revision Aug 2019| Content last modified Aug 2019
Click here for the Professional Version
NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version

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.

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), although it can occur any time of day.

Hyperemesis gravidarum differs from ordinary 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.


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.

Women with hyperemesis gravidarum often become so dehydrated that the balance of electrolytes, needed to keep the body functioning normally, is upset.

Hyperemesis gravidarum may cause the thyroid gland to become slightly and temporarily overactive (called hyperthyroidism).

Rarely, hyperemesis gravidarum continues after 16 to 18 weeks of pregnancy. If it does, it may severely damage the liver, causing jaundice and degeneration of liver tissue. If hyperemesis gravidarum severely damages the liver or causes severe dehydration, women can become confused.


  • A doctor's evaluation

  • 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

If doctors suspect hyperemesis gravidarum based on symptoms, they do blood and urine tests to determine whether dehydration is present and to check for electrolyte abnormalities, which may result from dehydration.

Ultrasonography is usually done to determine whether women have a hydatidiform mole (a disorder that initially resembles pregnancy) or more than one fetus (multiple births). Either condition may make vomiting more likely. Other tests may be done to rule out other possible causes of vomiting.


  • Nothing by mouth at first

  • Fluids given intravenously

  • Drugs to relieve nausea

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 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.

In very severe cases, the woman can be fed intravenously or via a tube passed through the nose and down the throat to the small intestine for as long as necessary, but this treatment is avoided as much as possible.

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.

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version
Others also read

Also of Interest


View All
The Breasts
The Breasts
3D Models
View All
Contents of the Female Pelvis
3D Model
Contents of the Female Pelvis