Nausea and Vomiting


The information provided below is for readers based in the United States of America. Readers outside of the United States of America should seek the information from local sources.

What is nausea and/or vomiting during pregnancy?

Many people refer to the nausea and/or vomiting in pregnancy as morning sickness but as most pregnant women already know, this isnt really accurate. You can actually be sick any time of the day or night, or even all of the time. Symptoms usually begin early in pregnancy (5-6 weeks), and tend to peak around the 9th week of pregnancy, and then stop sometime between the 16th and 20th week. Only about 5% of women will continue to have nausea and vomiting all the way through their pregnancy.

Why nausea occurs during pregnancy is not well understood. One explanation is that nausea and vomiting are caused by the bodys reaction to an increase in hormones during pregnancy. Other factors that may lead to it are an increase in stress, fatigue, or worsening of an already sensitive stomach.

You are more likely to get nausea and/or vomiting if you are pregnant with multiples, have a family history of nausea and vomiting in pregnancy, suffer from motion sickness or migraines, or are diagnosed with acid reflux.

How common is nausea and/or vomiting during pregnancy?

Nausea and/or vomiting are very common during pregnancy with 50 to 80% of women experiencing some nausea and 50% of women suffering from vomiting. Symptoms can range from mild to severe with only 0.3% to 3% of women suffering from the most severe form, called hyperemesis. Women with hyperemesis typically have vomiting that is difficult to stop even with medication, have lost at least 5% of their pre-pregnancy weight, and show signs of significant dehydration.

How is nausea and/or vomiting during pregnancy diagnosed?

The diagnosis of nausea and/or vomiting is usually made by the history you give your health care provider. If symptoms are reported as only mild or moderate, then no testing is needed before recommending treatment. However, if your symptoms are more severe or there is a concern for hyperemesis, then some testing is usually done to determine how aggressive the treatment should be. First, your health care provider will look at your weight, blood pressure, and an analysis of your urine. If these tests show signs of dehydration or significant weight loss then blood tests may be done.

Does nausea and/or vomiting cause problems during pregnancy?

Luckily, nausea and vomiting do not cause problems for most pregnancies. In fact, it has been found that women with nausea and vomiting are less likely to miscarry than other women.

If you have more severe vomiting or hyperemesis then you may need to be hospitalized to help control the symptoms and for IV fluid hydration. Rarely, medical complications can occur because of the symptoms.

Does nausea and/or vomiting during pregnancy cause problems for the baby?

The good news is that nausea and vomiting tends to be a part of a normal, healthy pregnancy with no problems for the baby. However, more severe symptoms or hyperemesis may increase the chances of delivering a small-for-gestational age baby or delivering preterm (before 37 weeks).

What to consider about taking medications when you are pregnant or breastfeeding:

You should think about:

  • The risks to yourself and your baby, if any, if you do not treat the nausea and vomiting
  • The risks and benefits of each medication you use when you are pregnant
  • The risks and benefits of each medication you use when you are breastfeeding

What should I know about using medication to treat nausea and/or vomiting during pregnancy?

Not everyone with nausea or vomiting in pregnancy needs to take medication to treat it. There are a number of things, besides medication, that can be done to help ease symptoms and get you through this part of the pregnancy (discussed below). If you feel that your symptoms require treatment or if they are severe enough to be affecting your relationship with your partner, family, or friends then you should talk with your health care provider about treatment options. Studies have shown that the earlier in pregnancy treatment is started the more successful it can be, so if you are having significant symptoms it is better to discuss what can be done about it sooner rather than later.

Who should NOT stop taking medication for nausea and/or vomiting during pregnancy?

Medications for treating nausea and/or vomiting of pregnancy may be discontinued at any time without causing any harm.

What should I know about choosing a medication for my nausea and/or vomiting during pregnancy?

The first medication to be tried should be a combination of pyridoxine 10 – 25 mg (vitamin B6) and doxylamine 10mg (Unisom). This combination has been used by over 30 million pregnant women and is considered safe to use while pregnant. There is some evidence that says this may be better at treating nausea but other studies show it treats both nausea and vomiting well. It was approved in 2013 as a single medication called Diclegis.

If pyridoxine and doxylamine do not improve the symptoms then there are several other medications that are safe to use in pregnancy that may work better. These include chlorpromazine (Thorazine), prochlorperazine (Compazine), promethazine (Phenergan), and metoclopramide (Reglan).

Ondansetron (Zofran) is also commonly used but it has the least amount of pregnancy safety information. A few studies have found an increased risk of heart defects if it is used before the 10th week of pregnancy. Ideally, one of the medications listed above should be used during the first 10 weeks of pregnancy and then, if they are not controlling the symptoms, use ondansetron.

Since each pregnant woman is unique, you may need to try several of these medications before finding one that helps. Or you may find that you need to use a combination of these medications. Good communication with your health care provider can help find the right medication for you.

You may find Pregistrys expert reports about the individual medications used to treat nausea and vomiting here. Additional information can also be found in the sources listed at the end of this report.

What should I know about taking a medication for my nausea and/or vomiting when I am breastfeeding?

Since nausea and vomiting of pregnancy is only present while you are pregnant, it should go away once you deliver the baby. If it continues after you have the baby, you should talk with your health care provider because it may mean that something besides pregnancy was causing the symptoms. If you do need treatment while you are nursing most medications are safe to use, but there is little specific data about these medications in nursing mothers.

What alternative therapies besides medications can I use to treat my nausea and/or vomiting during pregnancy?

There is evidence that taking a daily multivitamin starting at the time you conceive your baby may reduce your chances of getting nausea and/or vomiting in the first place. To help reduce your chances, it is recommended that you start taking a daily multivitamin as early as 3
months before trying to get pregnant.

Here are some of the most common things to try to reduce the nausea and/or vomiting:

  • Avoid environmental triggers – these include avoiding certain odors, stuffy rooms, humidity, heat, or things that may cause motion sickness
  • Getting enough regular sleep
  • Getting out of bed or changing positions slowly
  • Spending less time preparing food, which limits exposure to certain smells
  • Brushing your teeth right after eating or rinsing out the mouth frequently
  • Eating small meals every 1 to 2 hours that are high in protein rather than carbohydrates
  • Avoiding certain foods that trigger symptoms such as coffee or spicy, high fat, acidic, or odorous foods
  • Drinking cold, clear liquids and carbonated liquids
  • Trying peppermint candies or ginger (tea or candies) especially right after you eat

Some alternative treatments that may help are acupuncture, acupressure, hypnosis, or psychotherapy. P6 acupressure wrist bands (Sea-Bands) can be purchased in most pharmacies and may help with the symptoms.

What can I do for myself and my baby when I have nausea and/or vomiting during pregnancy?

The best things you can do for yourself and your baby for nausea and vomiting is to first try the suggestions above. You may also find that taking it easy during this time of the pregnancy can help make you feel better. If you find yourself feeling particularly bad, dont hesitate to discuss your symptoms with your health care provider. While a certain amount of nausea, and even vomiting, is expected if it is negatively affecting you or your relationships you should seek out better ways to manage your symptoms.

Resources for Nausea and/or vomiting during pregnancy:

For more information about nausea and/or vomiting during and after pregnancy, contact (800-994-9662 [TDD: 888-220-5446]) or check the following links:


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General information

It is very common for women to worry about having a miscarriage or giving birth to a child with a birth defect while they are pregnant. Many decisions that women make about their health during pregnancy are made with these concerns in mind.

For many women these concerns are very real. As many as 1 in 5 pregnancies end in a miscarriage, and 1 in 33 babies are born with a birth defect. These rates are considered the background population risk, which means they do not take into consideration anything about the health of the mom, the medications she is taking, or the family history of the mom or the baby’s dad. A number of different things can increase these risks, including taking certain medications during pregnancy.

It is known that most medications, including over-the-counter medications, taken during pregnancy do get passed on to the baby. Fortunately, most medicines are not harmful to the baby and can be safely taken during pregnancy. But there are some that are known to be harmful to a baby’s normal development and growth, especially when they are taken during certain times of the pregnancy. Because of this, it is important to talk with your doctor or midwife about any medications you are taking, ideally before you even try to get pregnant.

If a doctor other than the one caring for your pregnancy recommends that you start a new medicine while you are pregnant, it is important that you let them know you are pregnant.

If you do need to take a new medication while pregnant, it is important to discuss the possible risks the medicine may pose on your pregnancy with your doctor or midwife. They can help you understand the benefits and the risks of taking the medicine.

Ultimately, the decision to start, stop, or change medications during pregnancy is up to you to make, along with input from your doctor or midwife. If you do take medications during pregnancy, be sure to keep track of all the medications you are taking.

Medications for Nausea and Vomiting

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