Morning sickness often begins 4 to 6 weeks after conception. It may continue until the 4th month of pregnancy. Some women have morning sickness during their entire pregnancy. This happens most often for women who are carrying more than one baby.

It is called morning sickness because the symptoms are more likely to occur early in the day, but they can occur at any time. For some women, morning sickness lasts all day.

The exact cause of morning sickness is not known.

• Most experts think changes in the woman's hormone levels during pregnancy cause it.
• Other factors that can make the nausea worse include a pregnant woman's enhanced sense of smell and gastric reflux.

Morning sickness that is not severe does not hurt your baby in any way. In fact:

• It may even be a sign that all is well with you and your baby.
• Morning sickness may be associated with a lower risk of miscarriage.
• Your symptoms probably show that the placenta is making all the right hormones for your growing baby.

When nausea and vomiting are severe, a condition known as hyperemesis gravidarum may be diagnosed and may require treatment.

Changing what you eat may help. Try these tips:

• Eat a lot of protein and carbohydrates. Try peanut butter on apple slices or celery. Also try nuts, cheese and crackers, and low-fat dairy products like milk, cottage cheese, and yogurt.
• Bland foods, such as gelatin, frozen desserts, broth, ginger ale, and saltine crackers, also soothe the stomach.
• Avoid eating foods that are high in fat.
• Try to eat before you get hungry and before nausea occurs.
• Eat a few soda crackers or dry toast when you get up at night to go to the bathroom or before you get out of bed in the morning.
• Avoid large meals. Instead, have a snack as often as every 1 to 2 hours during the day. Do not let yourself get too hungry or too full.
• Drink plenty of liquids.
• Try to drink between meals rather than with meals so that your stomach does not get too full.
• Seltzer, ginger ale, or other sparkling waters may help control symptoms.

Foods that contain ginger may also help. Some of these are ginger tea and ginger candy, along with ginger ale. Check to see that they have ginger in them rather than just ginger flavoring.

Try changing how you take your prenatal vitamins.

• Take them at night, since the iron they contain may irritate your stomach. At night, you might be able to sleep through this. Also take them with a little food, not on an empty stomach.
• You may have to try several different brands of prenatal vitamins before finding one you can tolerate.
• You can also try cutting your prenatal vitamins in half. Take half in the morning and the other half at night.
• Taking just folic acid for a few weeks may be effective if you don't tolerate the large pill of prenatal vitamins.

Some other tips are:

• Keep your morning activities slow and calm.
• Avoid poorly ventilated spaces that trap food odors or other smells.
• Do not smoke cigarettes or be in areas where people are smoking.
• Get extra sleep and try to lessen stress as much as possible.

Try acupressure wristbands that apply pressure to specific points on your wrist. Often these are used to ease motion sickness. You can find them at drug stores, health food stores, travel stores, and online.

Try acupuncture. Some acupuncturists are trained to work with pregnant women. Talk to your health care provider beforehand.

Vitamin B6 (100 mg or less daily) has been shown to ease symptoms of morning sickness. Many providers recommend trying it first before trying other medicines.

Diclegis, a combination of doxylamine succinate and pyridoxine hydrochloride (Vitamin B6), has been approved by the US Food and Drug Administration (FDA) for treating morning sickness.

Do not take any medicines for morning sickness without talking with your provider first. Your provider may not advise medicines to prevent nausea unless your vomiting is severe and will not stop.

In severe cases, you may be admitted to the hospital, where you will receive fluids through an IV (into your vein). Your provider might prescribe other medicines if your morning sickness is severe.

• Your morning sickness does not improve after trying home remedies.
• You are vomiting blood or something that looks like coffee grounds.
• You lose more than 2 pounds (1 kilogram) in a week.
• You have severe vomiting that will not stop. This can cause dehydration (not having enough fluid in your body) and malnutrition (not having enough nutrients in your body).

Pregnancy - morning sickness; Prenatal care - morning sickness

Berger DS, West EH. Nutrition during pregnancy. In: Landon MB, Galan HL, Jauniaux ERM, et al, eds. Gabbe's Obstetrics: Normal and Problem Pregnancies. 8th ed. Philadelphia, PA: Elsevier; 2021:chap 6.

Bonthala N, Wong MS. Gastrointestinal diseases in pregnancy. In: Landon MB, Galan HL, Jauniaux ERM, et al, eds. Gabbe's Obstetrics: Normal and Problem Pregnancies. 8th ed. Philadelphia, PA: Elsevier; 2021:chap 53.

Updated by: John D. Jacobson, MD, Professor Emeritus, Department of Obstetrics and Gynecology, Loma Linda University School of Medicine, Loma Linda, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.