It is a condition characterized by severe nausea, vomiting, weight loss, and electrolyte disturbance. Mild cases are treated with dietary changes, rest, and antacids. More severe cases often require a stay in the hospital so that the mother can receive fluid and nutrition through an intravenous line (IV).
DO NOT take any medications to solve this problem without first consulting your health care provider. The exact causes of hyperemesis gravidarum are unknown. Risk factors include the first pregnancy, multiple pregnancy, obesity, prior or family history of HG, trophoblastic disorder, and a history of eating disorders.
Diagnosis is usually made based on the observed signs and symptoms. HG has been technically defined as more than three episodes of vomiting per day such that weight loss of 5% or three kilograms has occurred and ketones are present in the urine. Other potential causes of the symptoms should be excluded, including urinary tract infection and an overactive thyroid.
Treatment includes drinking fluids and a bland diet. Recommendations may include electrolyte-replacement drinks, thiamine, and a higher protein diet. Some women require intravenous fluids. With respect to medications, pyridoxine or metoclopramide are preferred. Prochlorperazine, dimenhydrinate, or ondansetron may be used if these are not effective. Hospitalization may be required. Psychotherapy may improve outcomes.
While vomiting in pregnancy has been described as early as 2,000 BC, the first clear medical description of HG was in 1852 by Antoine Dubois. HG is estimated to affect 0.3–2.0% of pregnant women. While previously known as a common cause of death in pregnancy, with proper treatment this is now very rare. Those affected have a lower risk of miscarriage but a higher risk of premature birth. Some pregnant women choose to have an abortion due to HG symptoms.
Signs and symptoms of hyperemesis gravidarum:
- Severe nausea and vomiting
- Food aversions
- Weight loss of 5% or more of pre-pregnancy weight
- Decrease in urination
- Extreme fatigue
- Low blood pressure
- Rapid heart rate
- Loss of skin elasticity
- Secondary anxiety/depression
Causes of Hyperemesis gravidarum
There are numerous theories regarding the cause of HG, but the cause remains controversial. It is thought that HG is due to a combination of factors which may vary between women and include genetics. Women with family members who had HG are more likely to develop the disease.
One factor is an adverse reaction to the hormonal changes of pregnancy, in particular, elevated levels of beta human chorionic gonadotropin (β-hCG). This theory would also explain why hyperemesis gravidarum is most frequently encountered in the first trimester (often around 8–12 weeks of gestation), as β-hCG levels are highest at that time and decline afterward. Another postulated cause of HG is an increase in maternal levels of estrogens (decreasing intestinal motility and gastric emptying leading to nausea/vomiting).
The pathophysiology of Hyperemesis gravidarum
Who’s at risk for hyperemesis gravidarum?
Some factors that could increase your risk of getting HG are:
- having a history of HG in your family
- being pregnant with more than one baby
- being overweight
- being a first-time mother
Trophoblastic disease can also cause HG. Trophoblastic disease occurs when there’s an abnormal growth of cells inside the uterus.
How is it diagnosed?
Your doctor will ask you about your medical history and your symptoms. A standard physical exam is enough to diagnose most cases. Your doctor will look for common signs of HG, such as abnormally low blood pressure or a fast pulse.
Blood and urine samples may also be necessary to check for signs of dehydration. Your doctor might also order additional tests to rule out gastrointestinal problems as a cause of your nausea or vomiting.
An ultrasound might be necessary to find out if you’re pregnant with twins or if there’s are any problems. This test uses sound waves to create an image of the inside of your body.
How is hyperemesis gravidarum treated?
Treatment for HG depends on the severity of your symptoms. Your doctor may recommend natural nausea prevention methods, such as vitamin B-6 or ginger.
Try eating smaller, more frequent meals and dry foods, such as crackers. Drink plenty of fluids to stay hydrated.
Severe cases of HG may require hospitalization. Pregnant women who are unable to keep fluids or food down due to constant nausea or vomiting will need to get them intravenously, or through an IV.
Medication is necessary when vomiting is a threat to the woman or child. The most commonly used anti-nausea drugs are promethazine and meclizine. You can receive either through an IV or as a suppository.
Taking medication while pregnant can cause potential health problems for the baby, but in severe cases of HG, maternal dehydration is a more concerning problem. Talk to your doctor about the risks associated with any method of treatment.