The study investigates the complex relationships between sex-selective abortion and family composition in two countries of the Southern Caucasus: Armenia and Azerbaijan. Data were drawn from maternity histories recorded in Demographic and Health Surveys (DHSs). In both countries, the relationship between the sex ratio of the next birth and the number of girls already born changed from negative to positive after 1992, when sex-selective abortion became prevalent. In Azerbaijan, but not in Armenia, a similar change was noticed for the relationship between the sex ratio of the next birth and the number of boys already born, this time from positive to negative. All changes in slopes were highly statistically significant. These findings indicate that sex-selective abortion was prevalent in both countries, and could work both ways in Azerbaijan. The results are interpreted in terms of ‘gender saturation’, that is a desire of families to better balance the composition of the family when too many children of the same sex are already born, which is consistent with opinion surveys indicating a preference for balanced families.