Why Do Women Experience Nausea in the Third Trimester of Pregnancy?

Many women experience nausea and vomiting during pregnancy. This is commonly referred to as “morning sickness” or “the joys of pregnancy”—a perfectly normal physiological response. Mild nausea and vomiting typically have no adverse effect on the pregnant woman. However, severe nausea and vomiting may significantly reduce appetite, thereby negatively impacting maternal health. So why does nausea occur in the third trimester?

Why Nausea Occurs in the Third Trimester

Sudden onset of nausea during late pregnancy may be related to dietary habits. In the third trimester, many women experience increased appetite and may eat more than usual. Consuming excessively greasy foods or overeating can trigger nausea; vomiting may temporarily relieve this discomfort. Additionally, the enlarged abdomen in late pregnancy exerts increased pressure on the stomach. When breathing becomes labored, women may experience gastric discomfort, chest tightness, or dizziness—symptoms that typically resolve after delivery. There is no need for excessive concern. It is important, however, to stay well-hydrated, eat smaller, more frequent meals, and avoid consuming large quantities of food at once. Excessive anxiety or stress can also provoke nausea; therefore, maintaining emotional calm is advisable. Moderate physical activity—such as a gentle walk after meals—may help alleviate nausea.

If nausea occurs in the third trimester, its underlying cause should be determined based on individual clinical symptoms and potential triggers. For instance, if nausea follows overeating, consumption of overly greasy or hard-to-digest foods, it likely reflects slowed gastrointestinal motility leading to indigestion. In such cases, medications that aid digestion and regulate spleen-stomach function may be beneficial in alleviating symptoms. In daily life, avoid overeating; instead, opt for smaller, more frequent meals and chew food thoroughly and slowly to ease digestive discomfort.

If nausea is severe, patients should promptly seek medical evaluation—including blood pressure assessment—and receive appropriate, symptom-targeted treatment. We hope this information proves helpful.