Vomiting in the Third Trimester

Pregnant woman in the bathroom

After dealing with morning sickness in early pregnancy, some women are surprised to experience vomiting in third trimester. Typically, the timeframe from 27 to 40 weeks is spent getting ready for labor and delivery, however, nausea and vomiting can still sneak up on some moms-to-be. Many of the common causes for vomiting are related to stomach viruses and digestion problems, but a chronic upset stomach can also be a sign of serious pregnancy problems.

Contact Your Physician About New Vomiting

If you had no morning sickness or vomiting during the first or second trimesters or if the vomiting comes on suddenly, it could be a sign of a serious complication. Anytime you experience unexpected vomiting during pregnancy, you should contact your physician. Pregnant women can dehydrate and lose vital nutrients quickly, so your doctor may want to run some tests to make sure everything is okay.

Reasons for Vomiting in Third Trimester

Some women think that vomiting in the third trimester is simply an extension of the morning sickness they had in the first few months. At times this may very well be the case, especially if your morning sickness was present throughout the second trimester. Since there are shifts in hormone levels during the third trimester, it's possible to go several weeks without vomiting only to have it return later. Some of the most common reasons for vomiting in third trimester include:


In addition to contractions and back pain, you may experience nausea and vomiting when labor begins. Your nausea and vomiting may become even worse during active labor. This could be due to the actual labor pains or if you happen to go into labor with a full stomach. If the vomiting or nausea is accompanied by any of the other signs of labor, contact your doctor or midwife right away. If you are full term, you will likely be delivering your baby soon.

Stomach Virus or Food Poisoning

Vomiting in the third trimester can due to a case of food poisoning or your body's reaction to something unusual that you ate. It can also be caused by a stomach virus. If your vomiting and diarrhea is severe, you should contact your doctor immediately since you can dehydrate very quickly. Symptoms of dehydration include, dry throat, lips and skin, dark yellow urine, headache, feeling lightheaded, constipation and possible Braxton Hicks contractions. Most times treatment includes rehydrating with water, however, if your symptoms worsen or you cannot even hold water down, you may need to go to the hospital for monitoring and IV fluids.

Fetus Size

As your fetus grows, you simply run out of room in the abdominal area. The growing uterus pushes up and puts pressure on the stomach, making it difficult for the mother to digest a large meal.

  • It is not unusual to experience acid reflux symptoms, including heartburn, during the third trimester due to the rapid growth of the uterus. You may notice more burping, some nausea as well as vomiting.
  • Typically eating smaller meals and/or taking antacids recommended by your doctor can help alleviate the symptoms.
  • However, if your symptoms worsen, you should contact your doctor.
Pregnant woman feeling sick

Serious Complications

If you're experiencing vomiting in the third trimester, it may be associated with more serious conditions which would need to be addressed immediately by a visit to the emergency room or contacting your doctor. A few of these conditions include:


Preeclampsia is a serious condition that is often accompanied by:

  • High blood pressure
  • Nausea
  • Vomiting
  • Headaches
  • Protein in the urine

If not treated, it could progress to eclampsia which is a severe case of preeclampsia that may cause seizures, coma, and even death of the mother or baby. Delivery of the baby is the most effective means of treating preeclampsia. If preeclampsia occurs before the 36th week, the mom is usually admitted to the hospital, put on bed rest, and monitored closely until delivery is possible. Medications can be used to treat some of the symptoms of preeclampsia, but delivery is the only cure.

Early Labor

While vomiting may be a symptom of labor at full term, it may also be a sign of premature labor. If you are less than 37 weeks gestational age and are experiencing symptoms, such as:

  • Consistent contractions
  • Nausea
  • Vomiting
  • Pelvic pressure
  • Leaking of fluid
  • Decrease in your baby's movement

These signs indicate you may be in premature labor. There are ways for your doctor to try to stop premature labor. Medication may be given to relax the uterus and stop the contractions, and bed rest may be prescribed as well. However, depending on the circumstances and regardless of the treatments attempted, your baby may still deliver early.

HELLP Syndrome

HELLP syndrome is rare and may occur later in pregnancy. It may also be associated with preeclampsia. This syndrome will alter or destroy red blood cells, elevate liver enzymes and affect how the blood clots. Symptoms of HELLP syndrome include:

  • Nausea
  • Vomiting
  • Right upper abdominal pain
  • Headaches

The treatment for HELLP syndrome is close monitoring of the pregnancy until your baby is delivered. You may be given medications such as blood pressure medication and steroids which will help baby's lungs mature quicker. Ultrasounds and nonstress tests will be a routine part of the monitoring as well. You may also be put on bed rest or admitted to the hospital. However, it is not unusual and may be necessary for your baby to be delivered early.

It Is Important to Contact Your Doctor

Just like during non-pregnant times, a woman may experience vomiting as a symptom of relatively minor health problems. However, any vomiting that happens more than once or progressively gets worse needs to be evaluated immediately by your OB/GYN doctor. In rare cases, this can be one of the first signs of a serious health issue that needs to be addressed right away.

Was this page useful?
Related & Popular
Vomiting in the Third Trimester