Twenty years ago I appeared in the film Motherless: A Legacy of Loss from Illegal Abortion, talking about the history of abortion. The 28-minute documentary, embedded above, profiles three women and one man whose mothers died of complications from abortion before its legalization. The film also includes the testimony of a former chief physician at Philadelphia General Hospital recalling the 32-bed ward for women being treated for what he called "botched, criminal abortions." Surprisingly, the film is still being used in classrooms, and its message - that the legalization of abortion following the Supreme Court's Roe v. Wade decision saved women's lives - is still relevant.

Tuesday is the 40th anniversary of the Roe v. Wade decision that found a woman's right to an abortion fell within the right to privacy protected by the Fourteenth Amendment to the United States Constitution. The decision invalidated all state laws restricting access to abortion in the first trimester of pregnancy, allowed states to regulate second trimester abortions in ways related to maternal health, and permitted third trimester abortion restrictions including allowing states to outlaw them. You can hear the oral arguments and read the full opinion.

As everyone knows, in the decades since that decision, vehement debates over abortion and the cultural divide those arguments represent have grown ever more virulent. Abortion battles have taken lives, with the assassinations of abortion providers and the bombings of clinics in which abortions are performed.  State laws restricting abortion have increased in number, limiting access to safe, legal abortions and making abortion more expensive. But restrictions do not decrease demand. As the Guttmacher Institute points out, "By age 45, nearly half of American women will have an unintended pregnancy and nearly 1 in 3 will have an abortion."

As we reflect today on the impact of Roe v. Wade, let us remember what it achieved. Maternal mortality declined significantly after the legalization of abortion, because abortions were performed by skilled professionals rather than untrained back-alley practitioners or by women themselves. The safety of legal abortion is documented in a study published last year in the journal Obstetrics and Gynecology reviewing the years 1998-2005. During that time death rates from induced abortion were 0.6 per 100,000. By way of comparison the death rate among women who delivered live neonates was 8.8 per 100,000.

Roe v. Wade was a public health success story. But the next chapter has yet to be written. It will involve reducing the rate of abortion by increasing access to contraception. A recent study confirmed that providing free birth control does just that. The Affordable Care Act mandates that private health insurance plans offer birth control and other preventive services. Let us hope that this will reduce the rate of abortion and let us urge that co-pays and other restrictions on birth control be eliminated.

Access to safe, legal abortion and to contraceptives are vital to protecting the public's health. They are means of ensuring the health of women. And, let us not forget, when women can access the professional medical services they need, fewer children grow up motherless.

Janet Golden, a Rutgers University history professor, specializes in the histories of medicine, childhood and women.

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