Is vomiting always symptom for early pregnancy?

Vomiting is not always a symptom of early pregnancy. While nausea and vomiting (morning sickness) are common during early pregnancy, they do not occur in all pregnant women. Some women may experience only mild nausea, while others may not experience any nausea or vomiting at all. Nausea and vomiting typically begin around the sixth week of pregnancy and peak around the ninth week. They usually resolve by the 12th to 16th week of pregnancy. Morning sickness is thought to be caused by rising levels of the hormone human chorionic gonadotropin (hCG), which is produced by the placenta during pregnancy.