The timing and causes of nausea and vomiting during pregnancy. Pregnant mothers may often feel nauseous and want to vomit, especially in the early stages of pregnancy. This is because changes in hormone levels in the body can affect the vomiting center in the brain, causing nausea and vomiting. . In addition, pregnant mothers\’ blood sugar levels and blood pressure are also affected, and some pregnant mothers are sensitive to certain foods, causing nausea. Coping method one: Dietary adjustment for