While men have always received more education than women in the past, this gender imbalance in education has recently turned around. For the first time in European history, there are now more highly educated women than men reaching the reproductive ages and looking for a partner. I expect that this will have profound consequences for the demography of reproduction because mating patterns have always implied that men are the majority in higher education. These traditional practices are no longer compatible with the new gender distribution in education. The objective of this paper is to formulate hypotheses about the consequences for reproductive behaviour in Europe. I expect the following causal chain between the reversal of the gender imbalance in education (RGIE) and fertility: RGIE creates a new, education-specific mating squeeze that affects the process and expected pattern of assortative mating, which in turns affects the timing, probability and stability of union formation, which eventually is expected to have implications for fertility. Each of the links in this chain are discussed in detail.