Ronald Reagan was elected in 1980. He was inaugurated, obviously in 1981.
Jimmy Carter was elected in 1976.
Roe v Wade was decided in 1973.
Right you are, but implementation was not instantaneous. The Supreme Court struck down several state restrictions on abortions in a long series of cases stretching from the mid-1970s to the late 1980s, but upheld restrictions on funding, including the Hyde Amendment, in the case of Harris v. McRae (1980).
This chart clearly shows the greatest increase in the rate of abortion during Carter's fiasco.