Analysis of information sources in references of the Wikipedia article "Dienogest" in English language version.
Dienogest is a 19-nortestosterone derivative that is approved in the European Union for the treatment of endometriosis. It is not available in the United States as a separate drug. It is only available in the oral contraceptive Natazia (Bayer Pharmaceuticals, Montville, NJ, USA) (estradiol valerate/dienogest), which is a newer four-phasic pack that contains dienogest.