Overview

Morning sickness is nausea and vomiting that occurs during pregnancy. And, despite its name, morning sickness can strike at any time of the day or night.

Many pregnant women have morning sickness, especially during the first trimester. But some women have morning sickness throughout pregnancy. Management options include various home remedies, such as snacking throughout the day and sipping ginger ale or taking over-the-counter medications to help relieve nausea.

Rarely, morning sickness is so severe that it progresses to a condition called hyperemesis gravidarum. This is when someone with nausea and vomiting of pregnancy has severe symptoms that may cause severe dehydration or result in the loss of more than 5 percent of pre-pregnancy body weight. Hyperemesis gravidarum may require hospitalization and treatment with intravenous (IV) fluids, medications and rarely a feeding tube.

Symptoms

Common signs and symptoms of morning sickness include nausea and vomiting, often triggered by certain odors, spicy foods, heat, excess salivation or — often times — no triggers at all. Morning sickness is most common during the first trimester and usually begins by nine weeks after conception. Symptoms improve for most expectant mothers by the mid to late second trimester.

When to see a doctor

Contact your health care provider if:

  • The nausea or vomiting is severe
  • You pass only a small amount of urine or it's dark in color
  • You can't keep down liquids
  • You feel dizzy or faint when you stand up
  • Your heart races

Causes

What causes morning sickness isn't clear, but the hormonal changes of pregnancy are thought to play a role. Rarely, severe or persistent nausea or vomiting may be caused by a medical condition unrelated to pregnancy — such as thyroid or liver disease.

Risk factors

Morning sickness can affect anyone who's pregnant, but it might be more likely if:

  • You had nausea or vomiting from motion sickness, migraines, certain smells or tastes, or exposure to estrogen (in birth control pills, for example) before pregnancy
  • You had morning sickness during a previous pregnancy
  • You're pregnant with twins or other multiples

You might be more likely to experience hyperemesis gravidarum if:

  • You're pregnant with a girl
  • You have a family history of hyperemesis gravidarum
  • You experienced hyperemesis gravidarum during a previous pregnancy

Complications

Mild nausea and vomiting of pregnancy typically won't cause any complications to you or your baby.

If left untreated, severe nausea and vomiting can cause dehydration, an electrolyte imbalance, decreased urination and hospitalization. Research is mixed on whether hyperemesis gravidarum causes poor weight gain for your baby during your pregnancy.

Prevention

There's no way to completely prevent morning sickness. However, avoiding triggers such as strong odors, excessive fatigue, spicy foods and foods high in sugar may help.

Sept. 22, 2018
References
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