Fourteen is rather young and even an older, young lady I would not condone having sex at home. What I would do is make certain there is communication and discussion about birth control and diseases and if she were seeing someone steady, I would help her select a OBGYN. This is not condoning anything, it is protecting your daughter.
I think fourteen is too young to date, let alone have sex! I know it depends on their maturity but if she were to become pregnant, how would she take care of it? Parents have to be parents and be responsible! These things (pregnancies) can happen to mature girls at a young age. I think parents should try to hold them back for as long as possible so they can get an education and enjoy their young life a little before settling down. Call me old fashioned or out of touch, but I think at fourteen, she should be involved in sports, music and keeping company with girlfriends.