Legal precedents for Roe? I suggest you read the decision. The majority opinion reviews the history of abortion jurisprudence. Roe is the first case to elevate abortion to a constitutional position.
It's hard to respond to your question, without knowing your thesis, but for earlier cases protecting various family rights see, for example, Stanley v. Illinois, 405 U.S. 645 (1972); Wisconsin v. Yoder, 406 U.S. 205 (1972); Ginsberg v. New York, 390 U.S. 629 (1968); Loving v. Virginia, 388 U.S. 1 (1967); Griswold v. Connecticut, 381 U.S. 479 (1965); Poe v. Ullman, 367 U.S. 497 (1961); May v. Anderson, 345 U.S. 528 (1953); Prince v. Massachusetts, 321 U.S. 158, 166 (1944); Skinner v. Oklahoma, 316 U.S. 535 (1942); Pierce v. Society of Sisters, 268 U.S. 510 (1925); Meyer v. Nebraska, 262 U.S. 390 (1923).
The court cited 143 precedents in the Roe decision- - not that the cases dealt with abortion.
There is an interesting analysis and criticism of Roe in the amicus brief filed in Webster v. Reproductive Health Services at 1988 U.S. Briefs 605 filed by the United States Catholic Conference.
Whether you are an abortion supporter or foe, Roe is a result oriented decision. Hope this is helpful.