In addition, Comstock-era restrictions on contraceptive sales raised birth rates, and in states in which they were in effect, 10 percent more children were reported as unwanted or ill-timed, accidentally conceived by their married parents.

Griswold erased these state-level legal differences and gave momentum to a large wave of social change. By 1970, most states and the federal government (which had restricted the inter-state transport of contraceptives under the federal Comstock Act) had repealed the anti-contraception provisions.

But greater access to contraception was just the beginning of the story. The effects of Griswold on children’s opportunities unfolded slowly over the next 50 years.

The Griswold decision created a natural experiment, making it possible to compare changes in states where restrictions were suddenly removed to those in which they had long been absent. The results reveal the remarkable impact of access to contraception. In formerly restrictive states, Griswold reduced birth rates and rates of accidental pregnancy. As more parents raised families under circumstances of their own choosing, children born after Griswold were more likely to finish college and earn higher family incomes.

Griswold also facilitated the creation of a national network of family-planning programs, which today serves roughly 6.7 million women. As this national network expanded, rates of unwanted childbearing fell further. The household income of the average child born after family planning programs started was raised by at least 2 percent.

As a series of legal decisions extended Griswold’s constitutional protections, unmarried women eventually benefited as well. These young women were increasingly likely to delay marriage, complete college, and enter occupations previously dominated by men. Young women between the ages of 18 and 21 gained more labor-force experience and earned 5 to 8 percent higher wages in their prime than women of the same age without access to contraception. The benefits of access to the Pill for unmarried women can explain roughly one-third of the convergence in the gender gap in earnings by the 1990s.

Many legal scholars still regard the Connecticut law that Griswold overturned as only a minor prohibition on contraceptive access. The law in question, though, significantly restricted economic opportunities for American families. As Congress considers revising family planning policies today, it should remember that lifting seemingly minor restrictions (or imposing news ones) on contraceptive access can shape the landscape of parenthood, careers, and children’s opportunities for many years to come.

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