Nausea and vomiting during pregnancy: A prospective study of its frequency, intensity, and patterns of change

OBJECTIVE: Our purpose was to provide a detailed description of patterns of nausea and vomiting of pregnancy. STUDY DESIGN: A prospective study was performed with 160 women who provided daily recordings of frequency, duration, and severity of nausea and vomiti ng. RESULTS: Seventy-four percent of women reported nausea lasting a mean of 34 .6 days. "Morning sickness" occurred in only 1.8% of women, whereas 80% rep orted nausea lasting all day. Only 50% of women were relieved by 14 weeks' gestation; 90% had relief by week 22. Data based on the McGill Nausea Quest ionnaire indicate that the nausea experienced by pregnant women is similar in character and intensity to the nausea experienced by patients undergoing cancer chemotherapy. CONCLUSIONS: Traditional teachings about nausea and vomiting of pregnancy a re contradicted by our findings. Standardized tools for measuring the distr ibution, duration, and intensity of nausea are applicable to the study of n ausea and vomiting of pregnancy and could be used in clinical trials to ass ess palliative measures.