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Nausea and vomiting in pregnancy - Background information
What is it?
- The majority of women feel nauseated or vomit in early pregnancy [Whitehead et al, 1992]. These symptoms are commonly referred to as 'morning sickness', but symptoms can occur at any time during the day.
- A UK study found that nausea and vomiting occur throughout the day in many women; of 292 women with symptoms, only 3.8% experienced nausea only in the morning. A similar pattern was observed for women with vomiting [Gadsby et al, 1993].
- Symptoms manifest before 9 weeks of gestation in almost all affected women and usually improve as the pregnancy progresses, resolving by 16 weeks of gestation in 90% of women [ACOG, 2004; Festin, 2006].
- Hyperemesis gravidarum is a diagnosis of exclusion characterized by prolonged and severe nausea and vomiting, dehydration, ketosis, and body weight loss in pregnancy [Nelson-Piercy, 1998; ACOG, 2004].
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