What Causes Nausea and Vomiting in Late Pregnancy?

Under normal circumstances, peristalsis in the human gastrointestinal tract moves downward. When gastrointestinal disorders occur, phenomena such as gastroesophageal reflux may arise. Patients may also experience nausea and vomiting; however, numerous factors can cause these symptoms. Nausea and vomiting are common during pregnancy—so what causes nausea and vomiting in late pregnancy?

What Causes Nausea and Vomiting in Late Pregnancy?

A common cause of nausea and vomiting in late pregnancy is indigestion (dyspepsia). This may result from overeating or consuming excessively greasy, spicy, or irritating foods. However, if nausea occurs, intrahepatic cholestasis of pregnancy (ICP) must not be ruled out. In a small proportion of pregnant women, ICP develops during the third trimester, leading to nausea, vomiting, and even jaundice and pruritus (itching) of the skin. Prompt blood testing—including measurement of serum total bile acids—is essential. To alleviate symptoms, patients should adopt a light, easily digestible diet, and follow a low-salt, low-fat regimen rich in fresh vegetables and fruits.

If nausea and vomiting occur during the third trimester, patients may first try eating easily digestible foods. It is important to rule out underlying gastrointestinal disorders, as well as mechanical compression of the stomach due to uterine enlargement—a common occurrence in late pregnancy—which can lead to dyspepsia or reflux esophagitis. If gastrointestinal disease is excluded, surgical conditions such as appendicitis must be further investigated. Finally, obstetric conditions—including ovarian cyst torsion and pregnancy-induced hypertension syndrome—may also secondarily cause nausea and vomiting.

Patients are advised to maintain a light, bland diet and seek timely medical evaluation and treatment upon noticing any discomfort, to prevent disease progression. We hope this information is helpful to you.