This sheet talks about nausea and vomiting during pregnancy (NVP). This information should not take the place of medical care and advice from your healthcare provider.

What is nausea and vomiting of pregnancy (NVP)?

NVP or “morning sickness” is the most common medical condition in pregnancy. It affects up to 80% of pregnant women. NVP symptoms can range from mild to severe. The symptoms can happen at any time during the day or at night. Symptoms can include nausea, dry heaves, retching and/or vomiting. NVP usually begins between 4-9 weeks of pregnancy, and peaks between 7-12 weeks. In most women, symptoms go away between 12-16 weeks of pregnancy. Up to 15% of women will continue to have symptoms up to 20 weeks of pregnancy or until delivery.

The most severe form of NVP is known as hyperemesis gravidarum (HG), which affects up to 3% of pregnant women. HG is a condition where there is severe nausea and constant vomiting that causes weight loss and dehydration (not getting enough water). Women with HG can require hospitalization.

Whether symptoms of NVP are mild, moderate, or severe, it can have a major impact on a woman’s quality of life. If NVP is affecting your ability to eat/drink, sleep, and/or perform your daily activities, speak with your healthcare provider.

If the symptoms of NVP first start at the 10th week of pregnancy or later they may be due to other causes and should be discussed with your healthcare provider.

Does having NVP increase the chance for miscarriage?

Miscarriage can occur in any pregnancy. Some studies have suggested that women with NVP might be less likely to have a miscarriage.

Does having NVP in the first trimester increase the chance of birth defects?

In every pregnancy, a woman starts with a 3-5% chance of having a baby with a birth defect. This is called her background risk. Most studies have not shown an increased chance for birth defects above the background risk when a women has nausea and vomiting during pregnancy.

Would having NVP cause other pregnancy complications?

Women with severe NVP or those who have HG are at a greater risk of getting dehydrated, as they might not able to drink enough water. This can cause medical complications for the mother. Some studies have found that HG might be associated with a slightly higher chance of having a baby that is smaller than expected.

Are there treatments for NVP?

It is helpful to treat NVP symptoms as soon as they occur, as it may be easier to get them under control if treatment or lifestyle changes are started right away.

There are treatments and interventions that might help pregnant women who have NVP. No one therapy will help 100% of women and a combination of therapies may be needed by some pregnant women. There are some prescription medications that have been used to treat NVP. The amount of information on the use of these medications in pregnancy and their side effects vary. You and your healthcare provider should work together to find the best treatment options for your symptoms.

Are there other lifestyle changes that I can try to help with my NVP?

It is helpful to treat NVP symptoms as soon as they occur, as it may be easier to get them under control if treatment or lifestyle changes are started right away. You and your healthcare provider should work together to find food and lifestyle changes that might work for you.

Some changes in food and lifestyle tips that have helped other women to lessen NVP symptoms and /or have NVP symptoms happen less often include:

  • Eating small meals or a snack every 1-2 hours,
  • Adding a protein source to each snack and each meal,
  • Drinking cold or partially frozen fluids daily (8 cups),
  • Keeping solids and liquids separate, by drinking 20 to 30 minutes before or after meals/snacks.
  • Eating bland foods that are gentle on the stomach, such as the BRAT diet.

Prenatal vitamins may trigger NVP, as the iron may cause greater symptoms, upset stomach and/or cause constipation. Discuss this with your healthcare provider if you are having trouble taking your prenatal vitamin.

Could my nausea and/or vomiting be due to something other than pregnancy?

Discuss your NVP and any other symptoms with your healthcare providers, as there are other medical conditions that cause nausea and vomiting. For example, symptoms of heartburn, indigestion and/or acid reflux (such as burning, burping, belching, or nausea at night) affect 40-85% of pregnant women, and over 50% of symptoms will appear during the first trimester. Some women find relief when avoiding fatty/acidic foods, and when elevating the head of the bed to sleep on an incline (raising the head higher than the abdomen).

Another example, a bacterial infection called Helicobacter pylori, has been associated with HG. Testing for this bacterium is recommended for women with a history of severe NVP or HG. If a woman is positive for this bacterium, she can be treated during her pregnancy. Your healthcare provider can help to determine if there are other possible medical causes for your NVP symptoms.

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