Abstract
Economic theory often assumes that the opportunity costs of having a child and financial constraints have a simultaneous but opposite influence on fertility. This empirical study aims to test the concomitance of these effects using the answers to an original survey carried out in 2003 amongst nearly 1000 French employees, giving information about the impact of their working schedule on the number of children they intend to have. The statistical analysis, based on a ‘ceteris paribus’ approach using Logit estimates, strongly confirms the simultaneous presence of these two explanatory dimensions.