When does morning sickness start and end?

In general, morning sickness starts in the first trimester, around week 5, and peaks by week 9 or 10, when levels of the pregnancy hormone human chorionic gonadotropin (hCG) are highest. For most women, morning sickness ends between 14 and 20 weeks.

When does morning sickness start?

Morning sickness – also called nausea and vomiting of pregnancy – affects different expecting moms at different times (and some not at all). But it usually starts around week 5 or 6 of pregnancy. For some women, that telltale queasy feeling is one of the first signs of pregnancy.

Unfortunately, morning sickness is very common – around 70% of pregnant women experience morning sickness in early pregnancy. On top of the nausea and vomiting, other symptoms of morning sickness include retching (dry heaving) and excessive salivation.

This unpleasant part of pregnancy is thought to be linked to the pregnancy hormone human chorionic gonadotropin (hCG) and estrogen. Both hormones rise rapidly in early pregnancy, and women with higher hCG levels (like moms of twins and multiples) often have more severe morning sickness.

For some expecting moms dealing with morning sickness, it's reassuring to keep in mind that in this case, feeling crappy means that your body is doing what it's supposed to – producing hormones that support your baby's development. 

But plenty of women with healthy pregnancies never have morning sickness, so if you don't experience it, don't be alarmed.

Can morning sickness last all day?

Calling it "morning sickness" is a little bit misleading – it often starts in the morning and lasts all day. Some women feel better as the day wears on, but others find their symptoms get stronger in the evening and their morning sickness gets worse at night.

Morning sickness usually isn't harmful to your health or to your growing baby, but it makes it hard to get through the day. A "mild" case can mean feeling nauseated for a short time every day and vomiting once or twice.

Many women describe it as feeling "blech" all the time. Many also have specific and significant food aversions. In more serious cases, nausea lasts for several hours and vomiting happens frequently.

When does morning sickness peak?

It varies from woman to woman, but symptoms tend to be the worst at around 9 or 10 weeks, when levels of hCG are at their highest. At 11 weeks, hCG levels start to fall, and by 15 weeks they've dropped about 50% from their peak.

Scientists believe that morning sickness may be the body's way of protecting your baby in early pregnancy from toxins and potentially dangerous foods. This theory makes sense because the first trimester – when most women have the strongest morning sickness – is the crucial period of development when all of your baby's organs and physical structures form.

When does morning sickness end?

Most women get relief from morning sickness by the second trimester, between 14 and 20 weeks. But some women with morning sickness continue to have symptoms beyond that, and a few women will experience it throughout their entire pregnancy.

What if I have severe morning sickness?

In the worst cases, some women experience hyperemesis gravidarum (HG), a severe form of morning sickness that can result in weight loss, dehydration, and other complications. Women with HG throw up so often that they can't keep down enough food and fluid, and may need to be treated in the hospital with IV fluids, vitamins, and medication.

If you aren't able to keep liquids down for more than 12 hours or solid foods down for 24 hours, call your healthcare provider. Also, let your provider know if your morning sickness lasts beyond 20 weeks of pregnancy, occurs for the first time after 9 weeks of pregnancy, or lessens and then returns.

Persistent nausea and vomiting can sometimes indicate another medical problem – or just make you miserable – so it's important to be seen and possibly treated. Many experts say that getting early help for morning sickness is important to prevent it from getting more severe.

Morning sickness remedies

Because morning sickness is common in pregnancy, some providers may minimize it. And some expecting moms are reluctant to seek help, in part because they're worried about taking medications that could affect their baby.

But there are safe ways to get relief from morning sickness:

• Switch to small, frequent meals. "Eat small amounts of food every 1 to 2 hours, avoiding an empty stomach – even put snacks by the bedside to eat during night," says Shannon Smith, M.D., FACOG, a board-certified ob-gyn, partner at Brigham Faulkner Ob/Gyn Associates, and member of BabyCenter's Medical Advisory Board.

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• Go bland. You may be craving spicy or ultra-sweet treats, but they could be the same foods causing nausea. Try a bland meal plan like the BRATT (bananas, rice, applesauce, toast, and tea) diet.

Eat small amounts of food every 1 to 2 hours, avoiding an empty stomach – even put snacks by the bedside to eat during night.

- Dr. Shannon Smith, ob-gyn

• Incorporate more protein. Eating protein will help you feel full longer, staving off nausea.

• Stay hydrated. Your body requires a lot of water during pregnancy. It's easier to become dehydrated, which makes nausea worse. Aim for at least 8 cups of water a day, and up to 12.

• Try ginger. There are plenty of ways to consume ginger, which is proven to relieve nausea, including ginger tea, ginger candies, and ginger ale. If you can't stand the taste but still want the benefits, try ginger capsules.

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• Acupuncture. Not only is acupuncture safe during pregnancy, it has been shown to relieve morning sickness.

• Acupressure wristbands. Though it hasn't been scientifically proven, anecdotal evidence suggests acupressure wristbands – initially developed to help with seasickness – help with nausea during pregnancy.

• Avoid triggering smells. If you're experiencing an aversion to certain scents, do everything you can to avoid them. Have your partner take out the trash, don't cook foods that cause nausea, and make sure your home has fresh airflow.

• Take your vitamins. Prenatal vitamins do more than just provide necessary nutrients to your body during fetal development; studies show these supplements reduce nausea and vomiting due to pregnancy. Adding an over-the-counter vitamin B6 supplement could also help.

Ask your provider about prescription medications. For her patients with severe morning sickness, Dr. Smith recommends Pyridoxine (vitamin B6) monotherapy or Doxylamine-Pyridoxine (Diclegis). Your diagnosis and prescription, of course, is up to your personal provider.