Morning sickness can start as early as a few weeks after conception and be the first sign of pregnancy. Morning sickness usually begins at some point during the first trimester and often resolves at 14–16 weeks of pregnancy.

More than 70% of pregnancies involve morning sickness at some point. In some cases, the nausea and vomiting may be mild, but in others, it is severe enough to interfere with daily life.

In this article, we look in more detail at when morning sickness starts, peaks, and is likely to end. We also discuss how to prevent and manage it.

A female experiencing the start of morning sicknessShare on Pinterest
Morning sickness usually begins in the first trimester.

Morning sickness can begin as early as a person’s missed period. It typically starts during the first trimester, before week 9. Despite its name, morning sickness can occur at any time of the day.

Morning sickness tends to get steadily worse during early pregnancy, peaking around the end of the first trimester before starting to improve in weeks 14–16. However, in 10–20% of pregnancies, nausea and vomiting persist beyond week 20.

In rare cases, people can develop severe morning sickness, or hyperemesis gravidarum (HE), which occurs in roughly 0.3–3% of all pregnancies. HE can last throughout pregnancy and may get worse during the second trimester.

Morning sickness is different for every person. Some of the symptoms that a person might notice are:

  • intense nausea
  • vomiting
  • stomach pain and cramping
  • dizziness and low energy

Many people find that certain factors trigger morning sickness, such as specific foods or smells.

When the nausea is severe enough to cause regular vomiting, a person may also experience symptoms of dehydration, including dark urine, infrequent urination, thirst, and feeling dizzy or faint.

If these symptoms occur, and a person cannot keep liquids down, it is important to call a doctor immediately. Without treatment, dehydration can be serious.

For most people, morning sickness is not a sign of a problem with the pregnancy, and it does not mean that the fetus is unwell. Some studies suggest that in the average case, morning sickness may be a positive sign.

The authors of an older 2000 study argue that morning sickness may be protective, as it often causes people to avoid foods that would once have posed the risk of infection.

Other studies show that people who get morning sickness are less likely to experience pregnancy loss, indicating that it is a sign of a healthy pregnancy.

There is no guaranteed way to prevent all morning sickness. However, people can try some techniques to reduce the frequency and severity of the symptoms. The American College of Obstetricians and Gynecologists (ACOG) recommend:

  • taking prenatal vitamins before and during pregnancy
  • taking vitamin B6
  • taking doxylamine, which is an antihistamine that is safe for use during pregnancy
  • eating smaller, more regular meals to prevent low blood sugar
  • increasing protein intake
  • drinking enough fluids to prevent dehydration
  • avoiding morning sickness triggers, where possible

If a person does not eat meat or fish, they can try increasing their protein intake by eating eggs and cheese. Nuts, tofu, quinoa, and seitan are among the protein sources suitable for those following a plant-based diet. Protein shakes may also be convenient for both vegans and vegetarians.

The iron in some vitamins can cause stomach pain. A person can ask a doctor or midwife about switching to a different prenatal vitamin if this occurs.

Some strategies can make it easier to deal with morning sickness. The ACOG suggest that people try:

  • Eating upon waking: Eating some crackers or dry toast upon waking in the morning can increase blood sugar and prevent someone from having to move around when they are hungry.
  • Ginger: Ginger tea, gum, or candy may help relieve nausea. A person can make ginger tea by grating fresh ginger root and steeping it in hot water.
  • Bland foods: Some people prefer to eat bland foods when they feel nauseated. The banana, rice, applesauce, toast, and tea diet (BRATT) is easy to digest, but finding foods that a person can keep down may take some trial and error.
  • Oral care: Frequent vomiting can damage the teeth, so it is a good idea to take extra care of them if morning sickness occurs. A person can dissolve a teaspoon of baking soda in a cup of water and use this solution to rinse their mouth after vomiting.
  • Asking for help, if possible: Morning sickness can make it difficult to go about daily tasks, such as work or looking after other children. Relatives and friends may be able to help in some cases, and staying close to home may make morning sickness easier to manage.

If home remedies fail and morning sickness is severe, a person can ask a doctor or midwife about prescription antinausea drugs.

Several factors can increase a person’s risk for severe morning sickness, or HE. According to the ACOG, a person is more likely to develop HE if:

  • they have close relatives who also experienced severe vomiting during their pregnancies
  • they experienced severe sickness during a previous pregnancy
  • they are pregnant with a female fetus
  • they have a history of migraine or motion sickness

If someone is concerned about their likelihood of getting HE, they can let a doctor know.

Severe morning sickness can become more difficult to control as a pregnancy progresses. As such, it is important to talk to a doctor about morning sickness early in the pregnancy, particularly if it is having a significant effect on daily life.

If the remedies that a doctor prescribes do not work, a person should follow up and ask for other options. They should go to the emergency department if:

  • their vomiting is severe, and they cannot keep fluids down
  • they are showing signs of dehydration
  • they develop nausea or vomiting after an injury or accident

Morning sickness is very common and usually starts early in pregnancy. For many people, it is the most difficult aspect of being pregnant. However, there are treatments and strategies that can prevent nausea and help someone cope.

Often, morning sickness goes away toward the end of the first trimester, but in a minority of people, it may continue for longer. A doctor or midwife can help with treating or managing this symptom.

Emergency medical help is necessary if someone shows signs of dehydration or cannot keep fluids down during pregnancy.