Heated exchanges between abortion rights demonstrators and those opposing abortion took place in front of the Supreme Court in January. (Michael S. Williamson/The Washington Post)

The National Academy of Sciences on Friday released the first in-depth report in more than 40 years about the state of science on abortion safety and quality in the United States. The work, conducted with support from six private foundations, found that abortions done in a clinic or with drugs appear to be safe in the vast majority of cases.

But the report's authors raise concerns about the geographic differences in access to abortion services.

“In many states, regulations have created barriers to safe, effective, patient-centered, timely, efficient, and equitable abortion services,” they write. “The regulations often prohibit qualified providers from providing services, misinform women of the risks of the procedures they are considering, overrule women’s and clinician’s medical decision-making, or require medically unnecessary services and delays in care.”

Among the study's interesting takeaways:

* Legal abortions in the United States, whether by medication or the three major surgical methods, “are safe and effective.”

* The quality of abortion care depends on where a woman lives.

* 95 percent of abortions are at clinics or other office-based settings.

* Despite much speculation about abortion's impact on future childbearing, the science shows that the procedure does not appear to increase the risk of secondary infertility, pregnancy-related hypertensive disorders, abnormal placentation, preterm birth or breast cancer.

* Having an abortion does not appear to be linked to such mental health consequences as depression, anxiety, and/or post-traumatic stress disorder.

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