Responsibility begins before conception.

No it doesn't. Sex is for recreation. There's no reason that conception should be the main thing on anyones mind. Because it isn't. Pregnancy is an unwanted side-effect the majority of the time, being completely responsible would mean abstaining from PIV sex altogether. People can only be careful. The availabiity of abortion pills and surgical abortions are a logical conclusion of individual freedom and modern culture in many ways.