Objective The purpose of this study is to examine what is known about the main fetal side effects when exposed to short-term use of NSAIDs during pregnancy. In addition it is examined how common the use of NSAIDs is in the general population, and among pregnant women in particular. Background NSAIDs have three main desired effects; analgesic, antiinflammatory and antipyretic effects. It is used to treat a variety of common conditions. NSAIDs act primarily through inhibition of the cyclooxygenase enzyme (COX), and inhibit prostaglandin synthesis. Prostaglandins play an important part in several of the body s physiological processes, and are known to have a central role in the ovulation, decidualization and implantation of the fertilized egg. NSAIDs mechanism of action and indications in the literature on the possible teratogenic effects is sufficient basis to exercise caution. Methods This project is a systematic literature review, based on a literature search in the PubMed database and McMaster PLUS. In addition, various searches in the prescription register, the Journal of the Norwegian Medical Association, the Institute of Public Health and other relevant resources has been made. Results and conclusion The prevalence of NSAID use among Norwegian, pregnant women is around 7 %. There are few good studies that have examined the fetal consequences of short-term NSAID use. The effect on fertility is uncertain. Some studies have shown an increased risk of spontaneous abortion and that the risk is higher when NSAIDs are used for more than one week. There seems to be no correlation between NSAID use and congenital malformations in general. For effects in late pregnancy it is seen a significant constriction of the ductus arteriosus, and a dramatic decline in amniotic fluid volume and fetal urine production rate just hours after initiation of treatment. However, these effects seem to be reversible. There is a particular need for more studies that examine short-term NSAID use, particularly for effects in the 1st and 2nd trimester.