Gender equity theory postulates that in every society there is an acceptable type of relationship between husband and wife. In other words, there is a set division of labor and responsibilities. A high level of gender equity means that labor and responsibilities are equally, or fairly equally divided, while low level signifies that there is an imbalance in both these matters.

In developed countries, low levels of gender equity are believed to lead to low fertility, while the contrary is the case in developing countries, the main cause being a change in lifestyle.