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Hyperemesis gravidarum

Hyperemesis gravidarum is extreme, persistent nausea and vomiting during pregnancy. It can lead to dehydration, weight loss, and electrolyte imbalances.


Most women have some nausea or vomiting (morning sickness), particularly during the first 3 months of pregnancy. The cause of nausea and vomiting during pregnancy is believed to be a rapidly rising blood level of a hormone called human chorionic gonadotropin (HCG). HCG is released by the placenta.

Some women have extreme nausea and vomiting during pregnancy. This can happen in any pregnancy, but is a little more likely if you are pregnant with twins (or more babies), or if you have a hydatidiform mole.


Symptoms of hyperemesis gravidarum are:

  • Severe, persistent nausea during pregnancy, often leading to weight loss
  • Light-headedness, weakness, headaches, or fainting
  • Constipation

Exams and Tests

Your health care provider will do a physical exam. Your blood pressure may be low. Your pulse may be high.

The following laboratory tests will be done to check for signs of dehydration:

Your provider may need to run tests to make sure you do not have liver and gastrointestinal problems.

A pregnancy ultrasound will be done to see if you are carrying twins or more babies. Ultrasound also checks for a hydatidiform mole.


Eating small, frequent meals and dry foods such as crackers may help relieve uncomplicated nausea.

Drink plenty of fluids. Increase fluids during times of the day when you feel least nauseated. Seltzer, ginger ale, or other sparkling waters may help.

Vitamin B6 (no more than 100 mg daily) has been shown to decrease nausea in early pregnancy. Ask your health care provider if this vitamin might help you. Another medicine called doxylamine (Unisom) has been shown to be very effective and safe when combined with Vitamin B6 for nausea in pregnancy. You can buy this medicine without a prescription.

If your nausea and vomiting is so severe that you and your baby might be in danger, your doctor will prescribe anti-nausea medicine. If your case is very severe, you will likely be admitted to the hospital. There, you will get fluids through an IV.

Outlook (Prognosis)

Nausea and vomiting is usually worst between 2 and 12 weeks of pregnancy and goes away by the second half of pregnancy. Sometimes it will last longer. With proper identification of symptoms and careful follow-up, serious complications for the baby or mother are rare.

Possible Complications

Too much vomiting is harmful because it leads to dehydration and poor weight gain during pregnancy.

Social or psychological problems may be associated with this disorder of pregnancy. If these problems exist, your health care provider needs to identify and take care of them.

When to Contact a Medical Professional

Call your health care provider if you are pregnant and have severe nausea and vomiting.

Alternative Names

Nausea - persistent - in pregnancy; Vomiting - persistent - in pregnancy


Cappell MS. Hepatic and gastrointestinal diseases. In: Gabbe SG, Niebyl JR, Simpson JL.Obstetrics: Normal and Problem Pregnancies

Gordon a, Platt J. Nausea and vomiting in pregnancy. In: Rakel D, ed.Integrative Medicine.

Hyperemesis Gravidarum. In: Ferri FF, ed.Ferri's Clinical Advisor 2015.

Jewell D, Young G. Interventions for nausea and vomiting in early pregnancy.Cochrane Database Syst Rev

Update Date 11/16/2014

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