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Hyperemesis gravidarum Wikipedia

Hyperemesis gravidarum (from the Latin for "extreme vomiting of the pregnant woman") is a severe form of morning sickness. It is considered a rare complication of pregnancy. The exact number of sufferers is difficult to pinpoint because symptoms of nausea and vomiting during pregnancy exist on a continuum, and there is no clear boundary between usual and common pregnancy sickness and hyperemesis (HG). Estimates of the percentage of pregnant women afflicted range from 0.3% to 2%.

The main symptom of HG is persistent and extremely severe nausea and vomiting that usually prevents the patient from performing their daily activities. In general, sufferers of HG lose a great deal of weight through vomiting; weight loss of up to 20% of the pre-pregnancy body weight is not uncommon in more severe cases. Many sufferers of HG are extremely sensitive to odors in their environment; certain smells may exacerbate symptoms.

Other symptoms of HG are direct consequences of excessive vomiting and the patient's inability to take in adequate nutrition. These may include dehydration, lightheadedness, fainting, and confusion or disorientation.

As compared to morning sickness, HG tends to begin somewhat earlier in the pregnancy and last significantly longer. While most women will experience near-complete relief of morning sickness symptoms near the beginning of their second trimester, some sufferers of HG will experience severe symptoms until delivery.

Studies have generally shown no difference in outcomes for children born to mothers with and without HG; this is especially true in cases where treatment has been aggressive and successful. Rare complications of untreated HG include Wernicke's encephalopathy, an irreversible psychosis caused by inadequate thiamine absorption. Renal or liver damage can also result.

Because HG tends to prevent sufferers from carrying out their daily activities, clinical depression|depression is a common complication. Non-medical complications may include the inability to perform self care and family care tasks and inability to perform employment duties.

Because of the potential for severe dehydration and other complications, HG is generally treated as a medical emergency. First-line treatment includes intravenous rehydration in a hospital and, if necessary, supplementation of electrolytes or B vitamins if vomiting has caused a deficiency. After IV rehydration is completed, patients generally progress to frequent small liquid or bland meals.

After rehydration, treatment focuses on managing symptoms to allow normal intake of food. Management of HG can be complicated because not all women respond to treatment. Coping strategies for uncomplicated morning sickness -- which may include eating a bland diet and eating before rising in the morning -- may be of some assistance but are unlikely to resolve the disorder on their own. There is evidence that ginger may be effective in treating pregnancy-related nausea.

Medication

While no medication is considered completely risk-free for use during pregnancy, there are several which are commonly used to treat HG and are believed to be safe.

The standard treatment in most of the world is Benedictin, a combination of doxylamine succinate and vitamin B-6. However, due to a series of birth-defect lawsuits in the United States against its maker, Merrill Dow, Benedictin is not currently on the market in the U.S. (None of the lawsuits were successful, and numerous independent studies and the FDA have concluded that Benedictin does not cause birth defects). Its component ingredients are available over-the-counter (doxylamine succinate is the active ingredient in many sleep medications), and some doctors will recommend this treatment to their patients.

Antiemetic drugs, especially ondansetron (Zofran), are effective in many women. The major drawback of ondansetron is its extremely high cost. In severe cases of HG, the Zofran pump may be more effective than tablets. Metaclopramide is sometimes used in conjunction with antiemetic drugs; however, it has a somewhat higher incidence of side effects. Other medications less commonly used to treat HG include corticosteroids and antihistamines.

In some women, medication is ineffective; if treatment is unsuccessful and weight loss continues, parenteral nutrition is usually prescribed.

• http://www.helpher.org/ Hyperemesis Education & Research Foundation

Last Modified:   2005-12-23