For women, having access to contraception at a young age may affect how much money they earn in their 30s and 40s, according to a new report from the Institute for Women's Policy Research released Wednesday.
The report examined the relationship between contraceptive access in the U.S. and a number of outcomes, including educational attainment, labor force participation, career outcomes and earnings. The findings come from decades of research on the economic impact of contraceptive access.
Women who have access to legal contraception beginning at ages 18 to 21 make 5% more per hour and 11% more per year by the time they're 40, compared to those who don't, according to the report. That translates to about 63 cents more per hour and $2,200 more per year.
The reason? Having access to birth control measures such as the pill allows women to delay having children, which means they can invest in higher education and choose an occupation, the study's authors, Anna Bernstein and Kelly M. Jones, noted.
The data came from interviews that were conducted between 1968 and 2003 and published in a 2012 study, but all the numbers have been converted to represent the dollar amount as of the year 2000, Jones tells CNBC Make It. (As a result, the calculation of 63 cents per hour and $2,200 per year is in 2000-era dollars.)
Of course, there are many factors that could impact women's future earnings that are not directly related to birth control, the researchers said. It is not possible to control a study for all of those factors, including family wealth, personality traits, soft skills, talents and aspirations.
For the study, Bernstein and Jones took a historic look at birth control and found that while access to contraception increased over the decades, so did women's ability to continue their education, remain in the workforce and earn more.
Their findings gel with other research on the widespread effects of birth control: Contraceptive access has been shown to increase women's college enrollment by 12% to 20%. The 15% bump in the women's labor force participation that happened from 1970 to 1990 was largely due to the pill, according to Bernstein and Jones.
On the other hand, an early birth has been shown to disrupt or delay women's ability to pursue secondary schooling and can have significant effects on their earning potential.
For example, a 2011 study found that women who have their first child fresh out of high school earn 30 fewer college credits than those who waited seven or more years to have kids. Each subsequent birth can further those effects, particularly for low-income households, according to the report.
Also, a study published in 2018 found that having children decreases women's earnings in Denmark over time, but not men's. When they had children, men's incomes still stayed on par with their peers who had no children.
Bernstein and Jones said the study is important because "the knowledge that [a woman] will have the future ability to control whether and when to have a child can shape a young woman's aspirations and life plans."
Contraceptives give women the freedom to invest in their human capital, and develop economic security, they added.
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