Iran has witnessed three major reversals of population policies since their inception in the 1960s. In response to a rapid decline in fertility to very low levels, the latest policy shift has led to the development of legislation that aims to encourage marriage and fertility, particularly the “Youthful Population and Protection of the Family” law approved in 2021. This study reviews the changes in population policy and their interrelations with fertility trends, focusing mainly on the shift towards pronatalist policies since 2005, and accompanying restriction of reproductive health and family planning services. Combining international and national sources, we position the new pronatalist drive in the country within the broader trend of government attempts to reverse fertility decline and promote conservative family values. Our study has three main aims. (1) We provide an overview of fertility trends, policy discourses and policy shifts in the context of the changes in the societal and political structures of Iran during the last half a century. (2) We highlight and discuss the most problematic features of the new Family Law, especially the legislation pertaining to maternal and reproductive health, access to abortion and contraception, and incentives supporting earlier marriage and higher fertility. (3) We discuss the likely consequences of the new legislation for maternal and child health and sexual and reproductive rights, for women in general, and the country’s socio-economic disparities. As well as violating reproductive rights, the new policy is unlikely to achieve its aim of initiating a sustained rise in fertility in Iran.