The vast majority of people experience nausea during pregnancy, often referred to as morning sickness, especially in the first three months of pregnancy. HG is the medical term for the most severe form of nausea and vomiting during pregnancy. It is more extreme than morning sickness. HG can lead to weight loss and dehydration, and may require intensive treatment.

This serious condition affects 0.3-10.8% of pregnant people. It can have adverse health effects on both the patient and the fetus.

• If you are experiencing symptoms, or have other concerns about your pregnancy, please speak with your health care provider.
• If you are pregnant and have severe nausea (for example, you are unable to drink for more than 8 hours or eat for more than 24 hours), seek medical care immediately.

HG can happen in any pregnancy, but is a little more likely if you are pregnant with twins or multiple babies, or if you have a hydatidiform mole. You are at higher risk if you have had the problem in previous pregnancies, are prone to motion sickness, or if a female relative has had HG.

You may be at higher risk if you weigh more than 170 pounds (77 kilograms), or have a history of menstrual pain, sensitivity to oral contraceptives, nausea before your period, migraine headaches, allergies, high blood pressure, or kidney or liver disease, among other risk factors.

Recently published research findings indicate that a hormone produced by the fetus/placenta known as GDF15 appears to be the primary cause of morning sickness and hyperemesis gravidarum. The severity of nausea and vomiting may be determined by a woman’s sensitivity to the hormone-women exposed to lower levels of GDF15 before pregnancy experience more severe symptoms.

Symptoms in pregnant patients may include:

• Severe, persistent nausea
• Vomiting more than 3 times a day
• Salivating a lot more than normal
• Weight loss (more than 5% of pre-pregnancy weight)
• Signs of dehydration (dark urine, dry skin, weakness, lightheadedness, or fainting)
• Constipation
• Not being able to keep food or liquids down
• Feeling dizzy or lightheaded
• Headaches

People with HG often experience vomiting, which can lead to weight loss and dehydration. Symptoms often last longer than morning sickness. If you have nausea and vomiting so extreme that you lose more than 5% of your pre-pregnancy weight, you may have HG. For example, if you weighed 170 pounds before pregnancy, this would be a weight loss of 13.5 pounds or more. Weigh yourself regularly and contact your health care provider if you are losing any weight during pregnancy, as they may want to monitor you more closely.

People with HG often experience vomiting, which can lead to weight loss and dehydration. Symptoms often last longer than morning sickness. If you have nausea and vomiting so extreme that you lose more than 5% of your pre-pregnancy weight, you may have HG. For example, if you weighed 170 pounds before pregnancy, this would be a weight loss of 13.5 pounds or more. Weigh yourself regularly and contact your health care provider if you are losing any weight during pregnancy, as they may want to monitor you more closely.

There are currently no medications approved by the FDA to treat HG. If your nausea and vomiting cause you to become dehydrated, you will need to receive fluids through your vein (intravenous therapy, also called an IV). You also may be given anti-nausea medicine. If nausea and vomiting is so severe that you and your baby might be in danger, you may be admitted to the hospital for treatment. If you cannot eat enough to get the nutrients you and your baby need, you may get extra nutrients either through an IV or a tube placed into your stomach.

Contact your health care provider if you are pregnant and have any of the following symptoms:

• Severe nausea and vomiting
• Signs of dehydration (dark urine, dry skin, weakness, lightheadedness, or fainting)
• Unable to tolerate any fluids for over 12 hours
• Lightheadedness or dizziness, or feeling confused
• Blood in the vomit
• Abdominal pain
• Weight loss of more than 5 pounds or 2.7 kilograms (Weigh yourself regularly to watch for excessive weight loss)

During pregnancy or as a new mother, you may feel overwhelmed at times. Mental health support and resources are available through the National Maternal Mental Health Hotline. It is free, confidential, and available 24/7. Call or text 1-833-TLC-MAMA (1-833-852-6262).