I present a method for estimating indicators of gender bias in reproductive behaviour, using microdata based on the own-children method. The method is first tested on a large sample from India with both birth history and household records. I then apply the method to Georgia, Indonesia, and Vietnam. My estimates demonstrate that the proportion of Georgian couples expressing a preference for sons in their fertility behaviour closely corresponds to the proportion resorting to sex selection at high parities. I show how individual Indonesian provinces provide examples of both son and daughter preference. The method also allows me to date the onset of sex imbalances at birth in Vietnam. The approach based on the own-children method therefore provides a unique tool for estimating the diversity and intensity of gender bias in reproductive behaviour.