I don't have teenage children, so I am speaking from my growing up experience on this. I think you should ask her straight out, or otherwise let her know that you know, but dont tell her about the spyware. You need to have open, honest communication with her about this for her safety and if she knows you spied, it will never happen. Just go with the "momvision" thing. I know my mom knew when I started.
I would not take such a heavy handed approach as some people suggest- again, it will prevent communication. Some people wait til they are married, but most dont, and its hard to preach something you didnt practice. And I dont believe it says anything about her being a good person or not.
Definitely take her to a doctor, and let her speak to him/her by herself if she wants. But you really need to stress the STD thing. Pregnancy is more scary to teenagers, but not nearly as bad as dying from irresponsible sex. You would be shocked at the number of teenagers that have an STD. I read something recently that like 80% have HPV. Love does not protect against anything, no matter what kids think. I was very responsible about sex when I was younger, because I knew people with HIV/AIDS. That was always my biggest fear. Maybe take her to volunteer with a hospice group or something, or at least show her the really graphic health class pictures.
I am not totally against the snooping. I think in some cases that spyware would be useful and called for, but if your daughter is as good as you say, maybe you should just try not using it for now. You already found out what you needed to. Unless you suspect things that might endanger her life like depression or drug use, I wouldnt get it it out again. Try to find out what is going on in her life by talking, and use the spyware as a last resort. I hope you are able to talk with her about all this. I know I was a very closed-off teenager, and a converation like that would have been mortifying for me. Good luck!