International audienceThis paper shows that differences in fertility across European countries mainly emerge due to fewer women having two children in low-fertility countries. It further suggests that childcare services are an important determinant for the transition to a second child to occur. The theoretical framework we propose suggests that (i) in countries where childcare coverage is low, there is a U-shaped relationship between a couple's probability of having a second child and the woman's potential wage, whereas (ii) in countries with easy access to childcare, this probability is positively related with the woman's potential wage. Data from the European Union Statistics on Income and Living Conditions (EU-SILC) confirm these im...