I've made the point before
@Lacius, that the analogy of forced organ transplant does not coordinate with the conditions of a forced pregnancy. It is a broken analogy of convenience. You apparently hate analogies, and only use them as a last resort. (You are bad at them)
A life is created and it is indentured to its condition. Those responsible to creating this indentured condition are responsible for maintaining it, or providing an alternative that is better, not worse--unless they are willing to sacrifice that life. Your organ transplant analogy will not acknowledge a situation where the person being forced to give an organ made the organ transplant necessary.
And yes, sex does lead to pregnancy, if done correctly. The pregnancy is a reasonable expectation. When would you argue that people should not be responsible for the consequences of their actions when the consequences are the expected outcome?