Nausea and vomiting in early pregnancy

More than half of pregnant women suffer from nausea and vomiting, which typically begins by the fourth week and disappears by the sixteenth week of pregnancy. The cause of nausea and vomiting in pregnancy is unknown, but may be due to the rise in human chorionic gonadotrophin concentration. In 1 in 200 women, the condition progresses to hyperemesis gravidarum, which is characterised by prolonged and severe nausea and vomiting, dehydration, and weight loss.

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatment for nausea and vomiting in early pregnancy? What are the effects of treatments for hyperemesis gravidarum? We searched: Medline, Embase, The Cochrane Library and other important databases up to September 2006 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

We found 22 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

In this systematic review we present information relating to the effectiveness and safety of the following interventions: acupressure, acupuncture, antihistamines, corticosteroids, corticotrophins, diazepam, dietary interventions other than ginger, domperidone, ginger, metoclopramide, ondansetron, phenothiazines, and pyridoxine (vitamin B6).