While a woman are pregnant, nausea and vomiting are normal. Up to 70% of all women get mild to moderate symptoms during the first three months (first trimester) of pregnancy. These symptoms are usually gone by the fourth month.
Although this condition is often called morning sickness, most women have symptoms throughout the day.
Very rarely, a pregnant woman may experience a more serious condition involving severe vomiting, dehydration, and weight loss. This is called hyperemesis gravidarum.