Researchers examined the expected number of births over a woman's lifetime, known as the total fertility rate, in the United States. They looked at data from 1940 to 2018, focusing on women across the country. The study did not report a specific sample size or follow-up period.
The main finding was that this fertility rate was highest for women during the post-World War II baby boom. The study did not report specific numbers, effect sizes, or safety concerns, as it was analyzing broad population trends rather than individual health outcomes.
It is important to be careful because this was an observational study of historical data. This means it can show a pattern but cannot prove what caused the fertility rate to be higher during that time. Many social, economic, and cultural factors likely played a role.
Readers should take from this that fertility rates in the U.S. have varied over time, with a notable peak in the mid-20th century. This information provides historical context but does not offer guidance for personal family planning decisions.