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Clinical Presentation of Nausea and Vomiting of Pregnancy (NVP)
Nausea and vomiting of pregnancy (NVP),the most prevalent medical condition in pregnancy,affects up to 85 % of pregnant women. The commonly used term “morning sickness” is misleading as the symptoms of NVP can occur throughout the day and/or night. In a study involving 160 pregnant women,74 % reported NVP symptoms,of whom,only 1.8 % experienced “morning sickness”,whereas,80 % experienced NVP throughout the day . Symptoms of NVP include nausea,gagging,retching and/or vomiting. Typically,symptoms of NVP appear between 4 and 9 weeks of pregnancy,and are usually most severe between 7 and 12 weeks of pregnancy. For the majority of pregnant women,symptoms subside between 12 and 16 weeks of pregnancy; however,for up to 15 % of women,symptoms continue up to 20 weeks gestation,and less than 10 % of women suffer throughout their entire pregnancy .
The severity of NVP can range from mild to severe. The most severe form of NVP is known as hyperemesis gravidarum (HG),which affects up to 0.3–2 % of pregnant women. HG typically requires hospitalization because of severe and persistent nausea and vomiting,weight loss greater than 5 % of pre-pregnancy weight,dehydration,electrolyte imbalances,and nutritional deficiencies . Women who have had NVP in a previous pregnancy are more likely to have recurrence of NVP in subsequent pregnancies with the severity of NVP typically increasing in subsequent pregnancies. A 2004 study demonstrated that initiating any antiemetic treatment prior to or on first day of symptoms effectively lessened the severity of symptoms and reduced the recurrence of HG in women who experienced NVP in a previous pregnancy . Because of the high recurrence rate of NVP symptoms (75–85 %),it is important for women to receive early treatment to reduce the severity of symptoms,with the aim of preventing the need for hospitalization and improving quality of life .","department":"
