Hyperemesis gravidarum is severe nausea and vomiting in pregnancy. It affects 1-2% of pregnant people, and the cause is unknown. It usually resolves by 20 weeks, but in some cases it may not fully resolve til after the birth.
If you have severe nausea and vomiting, contact your midwife early, before it gets to the point of dehydration or malnutrition. There are medications your midwife can prescribe to treat severe nausea and vomiting that may keep you out of hospital.
If you are showing signs of dehydration (dark urine, feeling very thirsty, light-headedness) or malnutrition (weight loss, feeling weak or cold, appearing pale) and you are unable to keep food or fluid down, contact your midwife. You may need to go to the hospital for treatment, such as rehydration or intravenous or intramuscular anti-emetics.