- Economic changes: The shift from an agricultural to an industrial economy meant that children were no longer as economically valuable as they had been in the past. In the agricultural economy, children were needed to help with farm work, but in the industrial economy, they were more of a financial burden.
- Educational opportunities: As educational opportunities for women increased, they began to delay marriage and childbearing in order to pursue their education. This led to a decline in the number of children born to each woman.
- Urbanization: As people moved from rural areas to urban areas, they began to live in smaller homes and apartments, which made it more difficult to have large families.
- Birth control: The development of effective methods of birth control, such as the birth control pill, made it possible for women to control their fertility and have fewer children.