Hyperemesis Gravidarum (HG)

HG is persistent and excessive vomiting that occurs before 22nd week of pregnancy and there is no other possible causes (e.g., gastrointestinal tract problem). HG is related to dehydration, ketonuria, electrolyte imbalance, and more than 5% body weight loss in mother. Severe HG also can cause  preterm birth, low birth weight and small of gestasional age. 

Get pregnant in younger age, primiparous (first pregnancy) increase the risk of getting HG. High hCG serum reach the highest concentration in the first semester when the worst symptom occurs.

Treatment of mild to moderate HG is antiemetic drugs, such as promethazine, metocloperamide. Severe HG treatment is rehydration with 5% dextrose (for the first 24 hours) then use normal saline or use normal saline only, correction of electrolyte imbalance, antiemetic drugs, and nasograstic tube (if necessary for nutrional support).  

Reference

McCarthy, F. P. et al., 2014,' Hyperemesis gravidarum: current perspectives ', Int J Womens Health, vol. 6, pp. 719-725.