Just note though - I was charting - checking mucous, postion and temping every day. We waited 3 days after ov to DTD - and didnt DTD for at least 7 days before i was due to ov..... and yet there is a little unit cooking away in here! (there was a second temp dip after we dtd after ov tough - doc believes i ov'd twice)..... just mentioning this because no contraception is 100% and you need to be comfortable (both you and him!!!) with whatever you decide.