Hyperemesis gravidarum

What is Hyperemesis gravidarum?

Hyperemesis gravidarum refers to vomiting during pregnancy that is so severe and persistent it causes weight loss, dehydration, nutritional deficiencies, electrolyte imbalance, pH imbalance (metabolic acidosis), and possible liver damage. Approximately two out of each 1,000 pregnant women have this condition so severely that they require hospitalization. If untreated, it can be fatal.

Hyperemesis gravidarum is believed to be related to the high hormonal levels in the blood due to the pregnancy, although the exact cause is unknown. Most women experience some nausea and vomiting during the first trimester of pregnancy, but hyperemesis gravidarum often persists for the duration of the pregnancy. A woman who vomits during pregnancy but continues to gain weight and is not dehydrated, does not have hyperemesis gravidarum.

How is it diagnosed?

History: A woman may complain of vomiting beginning early in pregnancy, which becomes so persistent and severe that it leads to weight loss and dehydration. Eventually she may be unable to keep any solids or liquids down.

Physical exam: The woman may present with weight loss of five to 35 pounds or an inadequate weight gain. There may be signs of dehydration (dry mucous membranes, poor skin turgor), slight jaundice (yellow coloring to skin or whites of eyes), rapid pulse (tachycardia), and/or low grade fever. Ophthalmic exam may reveal bleeding into the retina of the eye (hemorrhagic retinitis).

Tests: Blood studies are done to assess the electrolyte balance and rule out. A urinalysis can also help to detect acidosis. Liver function tests are done to identify pathological changes in the liver. Thyroid dysfunction can be associated with hyperemesis gravidarum, so a TSH and a free T4 may be done to evaluate thyroid function. A fetal ultrasound evaluation may be done to rule out the possibility of a hydatidiform mole instead of a pregnancy.

How is it treated?

When acid levels within the blood increase due to the loss of fluids, a serious condition called acidosis may occur. Acidosis depresses the central nervous system by interfering with the nerves' ability to communicate with each other (synaptic transmission). As the acid level rises, the malfunction of the nervous system worsens, and the individual may become disoriented, comatose, and even die.

Severe dehydration can lead to hypovolemia (abnormally low volume of blood circulating in the body). Untreated, hypovolemia can lead to shock, which is potentially fatal.

Another serious complication of hyperemesis gravidarum is bleeding within the retinas of the eye (hemorrhagic retinitis). Hyperemesis gravidarum sometimes affects the liver, deteriorating tissue similar to that seen in starvation.

Medications

• Intravenous fluid and electrolyte replacement if your condition is serious. Intravenous vitamin therapy and antinausea drugs may be required.
• If other drugs are prescribed for you, carefully follow instructions on the label.

Phenergan (Promethazine)

Activity

• Bed rest may benefit some patients.
• After recovery, resume activities slowly and as your strength allows. Work and exercise moderately. Rest often.

Diet

If the condition has not reached the point to warrant hospitalization for intravenous fluids, follow these instructions:

• If you feel nauseated in the morning, eat dry toast or saltine crackers before you get out of bed.
• Eat small, frequent meals.
• Don't eat fried or spicy foods; they increase nausea. Limit dairy products, especially butter, milk and cheese.
• Sit upright for 45 minutes after eating.
• If intravenous fluids are necessary, you will probably progress from them to a clear liquid diet, full liquid diet and then regular diet with small, frequent meals.

What might complicate it?

When acid levels within the blood increase due to the loss of fluids, a serious condition called acidosis may occur. Acidosis depresses the central nervous system by interfering with the nerves' ability to communicate with each other (synaptic transmission). As the acid level rises, the malfunction of the nervous system worsens, and the individual may become disoriented, comatose, and even die. Severe dehydration can lead to hypovolemia (abnormally low volume of blood circulating in the body). Untreated, hypovolemia can lead to shock, which is potentially fatal. Another serious complication of hyperemesis gravidarum is bleeding within the retinas of the eye (hemorrhagic retinitis). Hyperemesis gravidarum sometimes affects the liver, deteriorating tissue similar to that seen in starvation.

Predicted outcome

Predicted outcome is excellent. The condition is generally self-limiting, but death and serious complications are possible. With increasing sophistication of home care modalities, there is little reason for long-term hospitalization.

Alternatives

Conditions with similar symptoms include peptic ulcer, pyelonephritis, pancreatitis, cholelithiasis, cholecystitis, hepatitis, appendicitis, and hydatidiform mole.

Appropriate specialists

Obstetrician or gynecologist.

Last updated 7 August 2011