title: Nausea and vomiting during pregnancy: A prospective study of its frequency, intensity, and patterns of change.
abstract: OBJECTIVE
  Our purpose was to provide a detailed description of patterns of nausea and vomiting of pregnancy.
  
  
  METHODS
  A prospective study was performed with 160 women who provided daily recordings of frequency, duration, and severity of nausea and vomiting.
  
  
  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% reported 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 Questionnaire 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 are contradicted by our findings. Standardized tools for measuring the distribution, duration, and intensity of nausea are applicable to the study of nausea and vomiting of pregnancy and could be used in clinical trials to assess palliative measures.
authors.affiliation: Department of Psychology, McGill University, Montreal, Quebec, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Lacroix
authors.forename: E
authors.initials: E
authors.lastname: Eason
authors.forename: R
authors.initials: R
authors.lastname: Melzack
mesh_terms: D000328:Adult; D003710:Demography; D005260:Female; D006801:Humans; D008019:Life Style; D008499:Medical Records; D009325:Nausea / Q000453:epidemiology / Q000503:physiopathology* / Q000628:therapy; D010166:Palliative Care; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology / Q000503:physiopathology* / Q000628:therapy; D015995:Prevalence; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D014839:Vomiting / Q000453:epidemiology / Q000503:physiopathology* / Q000628:therapy