Nathanson was licensed to practice medicine in New York state in 1952 and became board-certified in obstetrics and gynecology in 1960. He was for a time the director of the Center for Reproductive and Sexual Health, then the largest freestanding abortion facility in the world. In 1974 Nathanson wrote: "I am deeply troubled by my own increasing certainty that I had in fact presided over 60,000 deaths." He also wrote that he performed an abortion on a woman whom he had impregnated.
Activism
Pro-abortion rights
Originally a pro-abortion rights activist, Nathanson gained national attention as one of the founding members along with Larry Ladder of the National Association for the Repeal of Abortion Laws. 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.
Anti-abortion
With the development of ultrasound in the 1970s, he had the chance to observe a real-time abortion. This led him to reconsider his views on abortion. He is often quoted as saying abortion is "the most atrocious holocaust in the history of the United States." He wrote the book Aborting America where he first exposed what he called "the dishonest beginnings of the abortion movement." In 1984, he directed and narrated a film titled The Silent Scream, in cooperation with the National Right to Life Committee, which contained the ultrasound video of a mid term abortion. His second documentary Eclipse of Reason dealt with late-term abortions. He stated that the numbers he once cited for NARAL concerning the number of deaths linked to illegal abortions were "false figures." Referring to his previous work as an abortion provider and abortion rights activist, he wrote in his 1996 autobiography Hand of God, "I am one of those who helped usher in this barbaric age." Nathanson developed what he called the "vector theory of life", which states that from the moment of conception, there exists "a self-directed force of life that, if not interrupted, will lead to the birth of a human baby."
Religious conversion
Nathanson grew up Jewish and for more than ten years after he became anti-abortion he described himself as a "Jewish atheist". In 1996 he converted to Catholicism through the efforts of the Rev. C. John McCloskey. In December 1996, Nathanson was baptized by John Cardinal O'Connor in a private Mass with a group of friends in New York's St. Patrick's Cathedral. He also received Confirmation and first Communion from the cardinal. When asked why he converted to Roman Catholicism, he stated that "no religion matches the special role for forgiveness that is afforded by the Catholic Church."
Nathanson married four times; his first three marriages ended in divorce. He died of cancer in New York on February 21, 2011 at the age of 84. He was survived by his fourth wife, Christine, and a son, Joseph, from a previous union, who resides in New Jersey.
Works
Aborting America Garden City, NY:Doubleday, 1979..
The Silent Scream.
The Abortion Papers: Inside the Abortion Mentality. New York:Frederick Fell, 1983..
Eclipse of Reason.
. Washington D.C.: Regnery, 1996.. Free to read at Internet Archive.