Hyperemesis Gravidarum
Condition
(Severe Morning Sickness; Persistent Vomiting of Pregnancy; HG)
Definition
Hyperemesis gravidarum (HG) is severe nausea and vomiting during pregnancy. It is not common.
Causes
The cause is not known. There are many thoughts about what may cause HG, such as:
- Hormone changes
- A lack of vitamin B
- Hyperthyroidism
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Risk Factors
HG is more common in young pregnant people. It is also more common in pregnant people who are Asian or Black.
Other things that may raise the risk are:
- HG during past pregnancies
- Past molar pregnancy—a growth of abnormal tissue in the womb
- A parent or sibling with HG
- A pregnancy of twins or more babies
- First time pregnancy
- Having some health problems, such as migraines or motion sickness
Symptoms
A person with HG may have:
- Nausea and vomiting in early pregnancy
- Weight loss
- Lightheadedness and fainting
Diagnosis
The doctor will ask about symptoms and health history. A physical exam will be done. Blood and urine tests may also be done.
Treatment
The goal of treatment is to manage symptoms to prevent weight loss and dehydration. Ways to treat HG are:
- Lifestyle changes, such as eating lots of small meals of bland, dry, high-protein foods
- Anti-nausea medicine
- Vitamin B6 to ease nausea
Prevention
The risk of HG may be lowered by taking prenatal vitamins for 1 month before becoming pregnant.
The American Congress of Obstetricians and Gynecologists
American Pregnancy Association
CANADIAN RESOURCES:
Health Canada
PregnancyInfo.ca—The Society of Obstetricians and Gynaecologists of Canada (SOGC)
The American Congress of Obstetricians and Gynecologists
American Pregnancy Association
CANADIAN RESOURCES:
Health Canada
PregnancyInfo.ca—The Society of Obstetricians and Gynaecologists of Canada (SOGC)
References
- Committee on Practice Bulletins-Obstetrics. ACOG practice bulletin 189: nausea and vomiting of pregnancy. Obstet Gynecol, 2018; 131 (1): e15-e30.
- Hyperemesis gravidarum. American Pregnancy Association website. Available at: https://www.americanpregnancy.org/healthy-pregnancy/pregnancy-complications/hyperemesis-gravidarum.
- Nausea and vomiting in pregnancy. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/nausea-and-vomiting-in-pregnancy.
- Severe vomiting in pregnancy. NHS website. Available at: https://www.nhs.uk/pregnancy/related-conditions/complications/severe-vomiting.
Contributors
- Marcin Chwistek, MD
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