Abstract Nausea and vomiting in pregnancy is a complex biopsychosocial syndrome, which is multifactorial, both in terms of aetiology and manifestation. In some women, symptoms resolve after the first trimester, but for others prolonged and unremitting nausea has an adverse effect on their daily lives. A minority develop hyperemesis gravidarum, for which hospital admission is required, but it is those with moderately severe nausea and vomiting …