Making the Diagnosis
Morning sickness isn't a disease and doesn't need elaborate diagnostic tests.
If a woman is pregnant and is throwing up (or constantly feels like throwing
up), a doctor will probably tell her that she has morning sickness. It's still
morning sickness if she's only throwing up in the evenings or at other times during the day.
No matter how severe the vomiting, a woman is only diagnosed with hyperemesis
gravidarum if she is losing weight or showing signs of severe dehydration.