Hey Tom,

I know the angst.
And you can trust her maybe, but not HIM.
Horny little boys will always find ways to trick the girls.
Never, ever leave them alone at that age.
And make sure the boys parents do the same as well.
(Generally they'll say, "Well John's a good little boy,you can trust him..")
Never believe this for a minute.

And what's worse, are the sleepovers. Make sure the girl has no older brothers or friends who are staying the night. Eyes and ears wide open.

Hopefully your wife will be able to be frank and confidential about ALL aspects of "dating"..no.... this is actual preparation for Hormone Day.
And be open enough so that if ANY problem comes up, including birth control or pregnancy (hopefully one precedes the latter and prevents the latter), that your daughter will be safe to come to her about ANYTHING in private.....that she'll be safe.
This in turn, may inspire a safety net in your household that will allow her to retreat if problems arise, without criticism or fear of rejection, or worse, abandonment.
And she can remind her that if she runs her body like a car, she'll need maintenance, which means a trip to the doctor, and her first pit stop is the ob/gyn doctor.
("Open wide.")

Then, let HER decide if she wants to go on the pill and when. If you think hanky panky may be just around the corner, buy her some condoms and let Mom give them to her.

Better to be safe, than sorry.

Just a fact of life.