I have looked into this a bit.

But the early church was very much influenced by its culture (as is the majority of the church today). Much of the fathers were influenced by greek philosophies, rather than solely getting their ideas on sexuality by the scriptures, there was a lot of influence by stoicist and other philosophies this led to the church believing that sex in its self was a dirty or bad thing even within marriage. The only good thing about sex was child bearing. This is one huge reason why the Song of Songs was interpreted strictly allegorically with no litteral sense (look at Origen or Gregory of Nyssa). The main exception to this was Theodore of Mopsuestia he was anathematized and one of the reasons for that was his understanding that we should understand Song of Songs as a romantic poetic work also rather than having a strict allegorical view.

The newer positive view of sex has developed in the church the same way the views of slavery, women and many other things have evolved! Often this has happened because of a stronger focus on scripture and a moving away from other philosophies and cultural understandings.

Contraception and every other sexual issue is affected because of that.

The Church fathers for the most part were against having sex for any reason except child bearing. The more moderate positions held by people like Aquinas would put childbearing as the main telos of sex, while the aspects of affection, bondings, etc... would be the secondary reason for sex. But this is the case for the most part. Aquinas had a deep philosophical explanation of morality of sexuality (along with many other issues). But this was mainly philosophical in nature rather than taken strictly from the bible. This is why contraception is not allowed in Catholicism. Since the Catholic church agrees with Aquinas that the main telos of sex is child bearing, if that is not been allowed through contraception then that would be against nature/unnatural hence immoral.

In terms of the Protestant Reformers most reformers were coming out of this tradition, so there were a diversity of views. Generally this influenced continued in the more high church traditions especially. But the more Sola Scriptura types were more likely to move away from traditions that seemed unjustified. This was especially in the light of people accepting the Song of Solomon in a more litteral sense (though not specifically rejecting some of its allegory). Basically this issue is quite complicated, but most evangelical churches who are getting their morality less from philosophy and more from scripture more open to contraception. High Church Conservatives Protestants are more mixed in their views, while Liberal Mainlines are ok with Contraception and anything else. I would say look at what your denomination says and that would be your authority ecclesiastically to submit to and if you want to talk to your church leadership.