From the book "When Women Stood"
Dating back to writings by Aristotle and Plato, the conventional thought was, until the birth of a child, it was not yet a member of society.
English Law 1557: "if one kills an infant in its mother's womb, this is not a felony."
The Roman Senate of Caesar Augustus's era was concerned about economic consequences of declining birth rates. As a result, they outlawed all birth control and abortion. NOT based on religion, morality, or any concerns about women.
During the Middle Ages, it was economics again that drove the Church to punish anyone who engaged in any form of abortion or birth control.
Historians have found abortion was accepted in ancient Greece and Rome.
The Old Testament has several legal passages that refer to abortion, but they deal with it in terms of loss of "property" and not sanctity of life.
The first known evidence of abortion comes from the Egyptian medical text Ebers Papyrus, 1550 BC.
In 1650 New England, abortion was legal and well documented. When the US Constitution was written, abortion was a legal medical practice.