We study the impact of a change in the content of religious practice on fertility decisions. We do so in the context of the Georgian Orthodox Church, where in December 2007, in a move to reverse declining fertility rates, the church’s Patriarch began to personally baptise third- or higher-parity children. At the macro level, using a synthetic control method and interrupted time series analysis, we find suggestive evidence that Georgian fertility rates did rise in response to this intervention. We validate this result using microdata on fertility histories and religion from a representative sample of Georgian women, exploiting variation in religion, ethnicity, marital status, and prior parity to identify women exogenously treated by the patriarch’s campaign. We find that the baptism campaign significantly increased fertility for treated women (i.e. Georgian Orthodox women, especially if married). It also increased marriage and reduced reported abortion. All of these outcomes were desired targets of the intervention. Our results show that even in industrialized, educated, low-fertility societies, traditional authority figures making use of religious discourses may be able to influence fertility patterns.