19 weeks pregnant without nausea but vomiting may be physiological phenomenon, acute gastroenteritis and other causes. 1. physiological phenomenon: some pregnant women pregnancy reaction may continue throughout pregnancy, may only show symptoms of vomiting, liver function tests are normal, so in 19 weeks of pregnancy without nausea but vomiting, and there is no other uncomfortable symptoms, it may be a pregnancy reaction, do not need special treatment. 2. Acute gastroenteritis: when eating spicy stimulation, cold and unclean diet during pregnancy, can cause acute gastroenteritis, can also be manifested as not nausea but vomiting symptoms, can also be accompanied by diarrhea, fever and other symptoms, combined with the history, clinical manifestations and routine stool examination can assist in the diagnosis. When vomiting without nausea occurs in the 19th week of pregnancy, it is necessary to go to the hospital in order to identify the cause and actively treat it.