Background: Gender equity theory in relation to fertility argues that very low fertility is the result of incoherence in the levels of gender equity in individually-oriented social institutions and family-oriented social institutions. The salience of gender to the fertility transition is strong in theory but not as strong in specification of testable hypotheses as has been pointed out in the literature.

Objective: The paper aims to clarify the specification of gender equity theory through a discussion of the difference between equity and equality and to suggest methods that might be applied to test the theory.

Methods: The theory is restated and further developed using literature from different disciplines. The method is described using a decomposition of fertility for women by human capital levels.

Results: The clarification of the theory includes a reminder that the theory relates to differences in fertility between countries and not to differences in fertility between women in the same country. In comparisons between countries, higher gender equity leads to higher fertility. In comparisons of fertility across women in the same country, higher gender equity does not necessarily imply higher fertility. In relation to measurement, a specification is suggested that effectively compares women across countries controlling for their level of human capital. Simple graphics are used to indicate ways in which fertility between countries may vary.

Conclusions: The paper concludes that it is likely the gender equity theory can be tested more readily by examining the behaviour across countries of women with higher levels of human capital.