What is Hyperemesis Gravidarum?

Hyperemesis Gravidarum (HG) is a medical condition characterized by extreme persistent nausea and vomiting during pregnancy.

HG ≠ Morning Sickness

“Hyperemesis gravidarum (HG) is diagnosed when nausea and vomiting is so severe that women are unable to eat and/or drink normally and have greatly limited daily activity. This is frequently accompanied by weight loss and electrolyte disturbance which can carry significant risks to the longer-term health of both mother and offspring. In the USA, HG is the leading cause of hospitalization in early pregnancy and the 2nd most common cause of pregnancy hospitalization overall.”

Fejzo, M, et al. “GDF15 Linked to Maternal Risk of Nausea and Vomiting during Pregnancy.” Nature Journal, 2023, www.hyperemesis.org/wp-content/uploads/2023/12/Fejzo-et-al.-2023.pdf.

Researchers are still unclear as to what causes HG and more studies are needed.

Researchers have investigated psychological causes such as stress, trauma, hysteria, and psychosomatic disorders, but psychological causes have been disproven.

HG ≠ Psychological Disorder

Some experts believe it might have a lot to do with the hormonal shifts that happen when you're pregnant, particularly elevated levels of the pregnancy hormone called human chorionic gonadotropin (hCG). High levels of hCG are often found in women with HG, and the severity of HG symptoms tends to coincide with the peak of hCG levels during the first trimester. The exact mechanism is not fully understood, but it's believed that hCG could directly stimulate the vomiting center in the brain or indirectly affect it through other hormonal pathways.

Recent research implicates Growth and Differentiation Factor 15 (GDF15). GDF15 naturally rises rapidly during pregnancy. Some women with HG have been found to have genetic variations in the gene which can lead to the production of abnormally high levels of the hormone or result in an unusual sensitivity to the hormone throughout pregnancy.

A mix of other elements like other genetic factors and/or problems with the digestive system could also play a role in triggering this condition.

What causes HG?

As vomiting is a common symptom of early pregnancy, is important to understand the symptoms of HG so that it is not written off as morning sickness. HG can be life threatening if not treated. A key marker the differentiate HG from morning sickness that you can identify at home is the inability to keep anything down (including water and your own saliva). Here is a chart to help you identify the symptoms. Rule of thumb, if you are feel that you’re are excessively vomiting and feeling abnormally unwell, get checked out by a doctor.

With HG being a rare condition, you may have to advocate for yourself or loved one when speaking with medical professionals. Do not downplay your symptoms. If you throw up every time you eat or drink, say that. If the medical professional assumes you’re experiencing typical morning sickness, express that you believe you may be experiencing HG or something more severe. It is appropriate and sometimes necessary to ask the medical professional, how have they ruled out the possibility of HG or any other potential underlying explanation. This ensures, the appropriate tests are administered. An HG diagnoses is typically determined by the loss of 5% or more of body weight and test results for dehydration.

Do I have HG?

Labs/Testing

  • Complete blood count

  • Electrolytes

  • Urine ketones

  • Weight loss

Treatment

Treatment

There is no cure for HG. However, some women may get some relief with nausea medication. The most common nausea medications prescribed for Hyperemesis are Zofran and Reglan. These medication can be taken orally, but due to vomiting may have to be taken as a rectum suppository or via a medical pump.

To address dehydration, you will likely receive fluids via IV. In some areas, there are options available to have an IV at home.

To address malnutrition, you may receive a banana bag or a nutrient-rich cocktail commonly used to correct vitamin and electrolyte deficiencies by IV. The bags typically contain thiamine, folic acid, and magnesium sulfate.

Vitamin B-6 (pyridoxine) is also typically prescribed as it is important for normal brain development and for keeping the nervous system and immune system healthy.