This is actually, sort of, the point of view of many Christian organizations: sexuality is to be used for procreation only.

> Likewise in your argument, cutting someone that is braindead from life support could be depriving them.

The question is always about in which situations it is ethical to decide about the existence of another person. I'm quite optimistic humans won't ever achieve a consensus about this. Which is good - it means that we stay aware of those questions.

Sorry about high-roading here - my point was that also in this case the ethic questions are not trivial because facilitating brainlessness is an active act during a similar phase of a human's existence as abortion. Because of this, I'm positive that jurisdictions allowing abortion will eventually allow growing brainless humans.