Hyperemesis Gravidarum

Hyperemesis gravidarum (HG) is an uncommon condition characterized by frequent, persistent, and severe vomiting and nausea during pregnancy. As a result, you may be unable to take in a sufficient amount of food and fluids. It can cause a weight loss of more than 5% of your pre-pregnancy body weight. This can also cause dehydration and vitamin and mineral deficiencies. Treatment may require hospitalization. HG is a more severe form of nausea and vomiting of pregnancy (NVP), also called morning sickness . Morning sickness affects anywhere between 70% to 80% of pregnant women. HG is estimated to occur in 0.5%-2% of pregnancies.

  • Causes

    There are many theories about the causes of HG, but none have been confirmed. HG is a complex disease that is likely caused by many factors. Some of these include:

    • Vitamin B deficiency
    • Human chorionic gonadotropin (hCG)—hyperemesis most severe during period of highest hCG levels
    • Hyperthyroidism —may be a result of hCG levels
    • High levels of estrogen
    • A multiple pregnancy
    • Brain nausea-control-center sensitivity to pregnancy changes
    The Brain May Be Cause of Nausea
    Brainstem and brain
    Copyright © Nucleus Medical Media, Inc.

  • Definition

    Hyperemesis gravidarum (HG) is an uncommon condition characterized by frequent, persistent, and severe vomiting and nausea during pregnancy. As a result, you may be unable to take in a sufficient amount of food and fluids. It can cause a weight loss of more than 5% of your pre-pregnancy body weight. This can also cause dehydration and vitamin and mineral deficiencies. Treatment may require hospitalization.

    HG is a more severe form of nausea and vomiting of pregnancy (NVP), also called morning sickness. Morning sickness affects anywhere between 70% to 80% of pregnant women. HG is estimated to occur in 0.5%-2% of pregnancies.

  • Diagnosis

    Your doctor will ask about your symptoms and medical history. A physical exam will be done. Tests may include the following:

    • Blood tests
    • Urine tests
    • Weight measurement—to determine if you have lost weight
    • Overall condition—ability to perform daily activities; psychological state of mind

  • Prevention

    Many of the conditions that lead to HG are not preventable. To help reduce your chance of nausea during pregnancy take these steps:

    • Avoiding smells, foods, or other things that stimulate nausea
    • Eating frequent small meals
    • Not allowing yourself to get too hungry or too full

  • Risk Factors

    Factors that may increase your chance of developing HG include:

    • History of HG in previous pregnancies
    • Molar pregnancy—an abnormal mass made up of placental tissue which may or may not contain some fetal tissue
    • Mother or sister with HG
    • A multiple pregnancy
    • Young maternal age
    • No previous completed pregnancies
    • First-time pregnancy
    • Obesity

  • Symptoms

    HG may cause:

    • Severe and persistent vomiting, beginning 4 to 6 weeks after conception, peaking 9-13 weeks, and usually improving and ending 14-20 weeks
    • Weight loss of greater than 5% of original, pre-pregnancy body weight
    • Decrease in urine
    • Dehydration
    • Rapid heartbeat
    • Headaches
    • Confusion
    • Lightheadedness and fainting

  • Treatment

    Treating HG symptoms early in pregnancy can make you less sick in the long run and can decrease recovery time. Because HG is caused by many factors that vary among women, it is difficult to find a treatment that works for everyone. Talk with your doctor about the best treatment plan for you. Treatment options include the following:

    If you are diagnosed with HG, follow your doctor's instructions.