Since the 19th century the Iranian state has been concerned with the size of its population, and policies directed to its increase or decrease have been closely involved with the purpose of nation building. None of these policies have been particularly successful, except for the effective family planning campaign of the 1980s that led to a remarkable drop in population growth, which currently stands at 1.3 per annum, below the replacement level. However, all the policies have failed to address the issue of infertility, which is widespread in Iran. It was against the background of such oversight that, from 1987, some pioneering physicians introduced IVF practices to the country and engaged with the Islamic jurists, whose endorsement of infertility treatment through IVF was deemed crucial to give the practices legitimacy. This article explores the process by which assisted reproductive technologies were legitimized in Iran in all their forms and which have placed the country in the lead among the Muslim countries in the Middle East in this respect. Within Iran, following the state's latest pronatalist policies, assisted reproductive technologies have been acknowledged as a means to help the state meet its new ambition of higher population growth.