Many women have problems with nausea and sometimes vomiting (morning sickness) during the first 16 weeks of pregnancy. For some women, morning sickness may be one of the first signs of pregnancy. The term “morning sickness” can be misleading, because symptoms can occur at any time of the day. The causes of morning sickness are not fully understood, but hormone changes that occur during pregnancy may play a role.

Morning sickness usually goes away as a pregnancy progresses. While many women feel better after the first trimester, some report ongoing nausea or vomiting through the second trimester. You may be able to gain some relief from morning sickness using home treatment, such as drinking tea. Talk to your doctor about safe medicines to treat your nausea and vomiting.

If you have severe, ongoing nausea and vomiting (hyperemesis gravidarum), see your doctor for treatment. This uncommon complication of pregnancy can lead to dehydration. You may need prescribed medicines, hospitalization, or both.

It is important to watch for signs of dehydration if vomiting develops. Even mild dehydration can affect other problems, such as constipation or heartburn, that may occur during pregnancy.

Symptoms of mild dehydration include:

• Increased thirst.
• Dry mouth and sticky saliva.
• Less urine output or dark yellow urine.

Symptoms of moderate dehydration include:

• Extreme thirst.
• Dry mouth with no saliva.
• Dry eyes; no tears.
• Less urination, or urinating 3 or fewer times in 24 hours. Urine is dark amber or brown.
• Arms and legs that may feel cool to the touch.
• Feeling very tired, restless, or irritable.
• Lightheadedness that is relieved by lying down.

Call your doctor if:

• You have symptoms of moderate dehydration.
• Vomiting is so severe that you are not able to drink fluids.
• Your vomiting has not gotten better with home treatment.