<Tr> <Th> Frequency </Th> <Td> ~ 75% of pregnancies </Td> </Tr> <Tr> <Td_colspan="2"> (edit on Wikidata) </Td> </Tr> <P> Morning sickness, also called nausea and vomiting of pregnancy (NVP), is a symptom of pregnancy that involves nausea or vomiting . Despite the name, nausea or vomiting can occur at any time during the day . Typically these symptoms occur between the 4th and 16th week of pregnancy . About 10% of women still have symptoms after the 20th week of pregnancy . A severe form of the condition is known as hyperemesis gravidarum and results in weight loss . </P> <P> The cause of morning sickness is unknown but may be related to changing levels of the hormone human chorionic gonadotrophin . Some have proposed that it may be useful from an evolutionary point of view . Diagnosis should only occur after other possible causes have been ruled out . Abdominal pain, fever, or headaches are typically not present in morning sickness . </P>

What is the meaning of morning sickness in pregnancy