Griswold v. Connecticut was the U.S. supreme court decision that overturned laws banning contraception – at least, for married couples. It wasn’t the first SCOTUS decision to mention the concept of privacy, but it was a major one.
Research:

SYMHC Classics: Nelson Pill Hearings
38:25

Behind the Scenes Minis: Alaska and Contraceptives
28:17

The IUD: A History
44:41