There is strong evidence that, in addition to individual and household characteristics, social interactions are important in determining fertility rates. Social interactions can lead to a multiplier effect where an individual’s ideas, and fertility choice, can affect the fertility decisions of others. We merge all available Demographic and Health Surveys to investigate the factors that influence both individual and average group fertility. We find that in the early phase of the fertility transition the impact of a woman’s education and experience of child death on her group’s average fertility are more than three times as large as their direct effect on her own fertility decision.