Nausea and vomiting in early pregnancy.

To study the problem of nausea and vomiting in early pregnancy an epidemiological survey was undertaken, obtaining information from 500 consecutive antenatal patients. Seventy-six percent of women complained of symptoms during the first trimester, and in only 27% had the symptoms resolved by the twelfth week. Job efficiency was markedly impaired. Women who suffered nausea premenstrually, or on the oral contraceptive pill, were much more likely to develop symptoms, lending credence to a hormonal etiology for the condition.