Hyperemesis gravidarum (HG) is a condition at the extreme end of the pregnancy sickness spectrum, estimated to affect 1-2 % of pregnant women. This narrative review provides an overview of the current literature concerning the nutritional implications and management of HG. HG can persist throughout pregnancy, causing malnutrition, dehydration, electrolyte imbalance and unintended weight loss, requiring hospital admission in most cases. In addition to its negative effect on maternal, physical and psychological wellbeing, HG can negatively impact fetal growth and may have adverse consequences on the health of the offspring. HG care and research have been hampered in the past due to stigma, inconsistent diagnostic criteria, mismanagement and lack of investment. Little is known about the nutritional intake of women with HG and whether poor intake at critical stages of pregnancy is associated with perinatal outcomes. Effective treatment requires a combination of medical interventions, lifestyle changes, dietary changes, supportive care and patient education. There is, however, limited evidence-based research on the effectiveness of dietary approaches. Enteral tube feeding and parenteral nutrition are generally reserved for the most intractable cases, where other treatment modalities have failed. Wernicke encephalopathy is a rare but very serious and avoidable consequence of unmanaged HG. A recent priority-setting exercise involving patients, clinicians and researchers highlighted the importance of nutrition research to all. Future research should focus on these priorities to better understand the nutritional implications of HG. Ultimately improved recognition and management of malnutrition in HG is required to prevent complications and optimise nutritional care.
Keywords: Hyperemesis gravidarum; Maternal malnutrition; Pregnancy nausea vomiting; Pregnancy nutrition; Pregnancy sickness.