Well I don't have a girlfriend since I'm married, but I answered the first choice since it was only by accident when my wife thought her period was either over or not starting yet. I didn't discover it until after pulling out and while it only mildly bothered me, I never did it deliberately during that time as I've never been big on the sight of blood and I did find find it somewhat groady.
This was despite the fact she seemed to be super-horny around that time and even begged me a few times to lay down a towel, but I still couldn't do it with the foreknowledge.
That's been one of the great things about her being post-menopausal is those days of timing sex each month (and having to worry that birth control might fail) have been long behind us and we can have sex anytime we want.