I use it combined with FAM. FAM is my primary form of contraception, withdrawal secondary. I lost my virginity to my current boyfriend a year ago and we've never had any slip-ups. He has practiced withdrawal in previous relationships and has enough confidence in it to use it on its own. I added FAM because we wanted him to be able to finish inside me. I prefer to abstain from PIV-sex during my fertile window. We are long-distance (see each other approx. every second weekend) and that combined with surprisingly good timing has led to us not having the opportunity to/problem of have sex during my fertile window very often. When we do find ourselves together on fertile days we usually stick to non-PIV sex.