Nathanson was born in New York. He graduated in 1949 from McGill University Facility of Medicine in Montreal. He has been licensed to practice in New York state since 1952 and became board-certified in obstetrics and gynecology in 1960.
As a younger man, he had been strongly pro-choice, and he states that he performed an abortion on a woman who had become pregnant by him. He later gained national attention by then becoming one of the founding members of the National Association for the Repeal of Abortion Laws, now known as NARAL Pro-Choice America. He worked with Betty Friedan and others for the legalization of abortion in the United States. Their efforts essentially succeeded with the Roe v Wade decision. He was also for a time the director of the Center for Reproductive and Sexual Health (CRASH), New York's largest abortion clinic. Nathanson has written that he was responsible for more than 75,000 abortions throughout his pro-choice career.
The development of ultrasound, however, in the 1970s led him to reconsider his views on abortion. He is now a staunch supporter of the pro-life movement. In 1984, he made the documentary The Silent Scream, which showed an abortion from the perspective of ultrasound. His second documentary Eclipse of Reason dealt with late-term abortions. He has also stated that the numbers he once cited for NARAL concerning the number of deaths linked to illegal abortions were "false figures".
He has written the books Aborting America and The Hand of God. Although he grew up Jewish, he described himself as a "Jewish Atheist" and later converted to Catholicism in 1996 through the efforts of Fr. C. John McCloskey. Before that conversion, he had divorced three times.
Nathanson has served as an expert witness in several medical malpractice cases. Although he has served as an expert on behalf of both defendants and plaintiffs, the vast majority of his efforts have been on behalf of the plaintiffs.
- Aborting America, 1979
- The Silent Scream, 1984 (Documentary)
- Eclipse of Reason, 1987 (Documentary)
- The Hand of God, 1996
- Nathanson M.D., Bernard. The Hand of God. Regnery Publishing, Inc.: Washington D.C., 1996. pp. 58-59. (ISBN 0-89526-463-3) "In the mid-sixties I impregnated a woman...and I not only demanded that she terminate the pregnancy...but also coolly informed her that since I was one of the most skilled practitioners of the art, I myself would do the abortion. And I did."
- Nathanson M.D., Bernard. "Aborting America". Double Day & Company, Inc.: Garden City, 1979. pp. 193. (ISBN 0-385-14461-X) "I confess that I knew the figures were totally false, and I suppose the others did too if they stopped to think of it."
- The Silent Scream
- Criticism of Dr. Nathanson from the Pro-Choice Action Network
- 'Pro-choice' co-founder rips abortion industry - Doctors, clinic staffers tell shocking behind-the-scenes story
- A Pro-Life article from the conservative Harvard Salient mentioning him
- EWTN article
- NARAL and Dr. Bernard Nathanson on YouTubecs:Bernard Nathansonpt:Bernard Nathanson