H yperemesis gravidarum (HEG) is a condition of persistent vomiting inpregnancy that often occurs in the first trimester which can cause variousdisorders of the body's balance, such as dehydration, electrolyte disturbances,metabolic and nutritional deficiencies and even death. The etiology is not certainbut nausea and vomiting are considered to be multifactorial problems. Some of therisk factors that play a role are hormonal, psychological, parity, nutrition andallergies. With regard to parity, the number of pregnancies and the length ofpregnancy have an effect on nausea and vomiting in pregnancy. Based on theliterature search, it is known that HEG occurs more in primigravida mothers dueto physical and psychological factors who are not ready to experience hormonalincreases and other changes. Also in mothers with high parity due topsychological factors and increased pregnancy hormones. Nutritional status as arisk factor for hyperemesis gravidarum can be assessed using BMI (body massindex) before pregnancy. Hyperemesis gravidarum (HEG) is more common inundernourished pregnant women because they have low pre-pregnancy estrogenlevels. Meanwhile, mothers with excess BMI tend to hypoventilate mainly due toincreased intra-abdominal pressure, but there is still no clearer mechanism.However we still need more research to reduce the incidence of HEG so that thehealth status of the mother and fetus will be optimal.