Hyperemesis gravidarum is extremely severe nausea and excessive vomiting during pregnancy.
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.
The thyroid gland may 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.
Doctors 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—see Hydatidiform Mole) 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.
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).
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, the woman is fed via a tube passed through the nose and down the throat to the small intestine for as long as necessary.
If vomiting continues despite treatment and causes continuing weight loss, jaundice, and abnormal heart rhythms, ending the pregnancy is an option. Women can discuss this option with their doctor.
Last full review/revision August 2013 by Antonette T. Dulay, MD