In 1996, the Lancet reported that there was a lively trade of surgeons performing hymenoplasty to give women the illusion of virginity before marrying, despite the fact that Al-Azhar (the highest Islamic institution in Egypt) had condemned hymenoplasty and the Egyptian Medical Association had forbidden its members from performing the procedure. Ethnographic research in Egypt conducted during 2008-2009 showed that, like the Lancet, a majority of Egyptian doctors interviewed believe that hymenoplasty is both illegal and haram (i.e. religiously prohibited), and hymenoplasty is not taught in Egyptian medical schools. Yet a careful investigation during the same years that these doctors were interviewed revealed that there was no Egyptian law prohibiting hymenoplasty, it has never been condemned by the ethics committee of the Egyptian Medical Syndicate, a 2007 fatwa (ruling of religious jurisprudence) issued by the Grand Sheikh of Al-Azhar University pronounced hymenoplasty religiously permissible under certain circumstances, and a 2008 fatwa from a Dar al-Iftaa mufti (jurisprudist) declared that any doctor asked to perform hymenoplasty should do so. Why do Egyptian medical authorities refuse to teach or openly perform a procedure that has been approved by one of the highest Islamic authorities in the country, and why do many doctors believe it is illegal when it is not? This paper, which is based on archival and ethnographic research in Cairo, Egypt, explores these paradoxes. Using the case study of hymenoplasty, it examines how key institutions - in this case, Islamic schools of jurisprudence and fatwas, medical schools, and the media - shape interpretations of the moral implications of new medical technologies, as well as their availability. It also provides a window onto the role of religious authorities in deciding questions of moral behaviour in the everyday lives of Muslims. Finally, studying debates about hymenoplasty in Egypt reveals what kinds of sexualities are popularly imagined to emerge from (and create the need for) this reproductive health technology.