For severe, persistent vomiting during pregnancy see the information on hyperemesis gravidarum .
Morning sickness is extremely common, occurring in about half of all pregnant women.
The problem usually begins during the first month of pregnancy and continues until the 14th to 16th week. Emotional stress , traveling, or some kinds of food may aggravate the problem. However, it may be caused by either hormonal changes or lower blood sugar during early pregnancy . The information provided herein should not be used for diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions.