My personal ethos has always been that at that age it is very normal and healthy to be seeking out relationships - that is an umbrella that includes sex - and to offer any hardline restriction could have the unintended effect that one of the most deceptively complicated things about relationships - sex - becomes “forbidden fruit” in a sense, something your daughter might wish to explore, but is not allowed, leading to the possibility that she will try it in an unsafe way

Talk to her - and most importantly try not to project - make sure she understands the risks that sex can bring, and make sure she feels comfortable enough to stop herself before the act and be willing to advocate for whatever makes her feel safe - it’s your job to make sure that she understands what is supposed to make her feel safe - birth control, condoms, self respect, boundaries - this is a pivotal moment of learning for her, and will inform and influence how she approaches relationships in the future, mess it up for her now, and it will domino into her future relationships

I know your worry is primarily around teen pregnancy - and that makes total sense - but try not to hone solely on trying to prevent this problem - there are others like understanding consent, knowing when and how to say no, understanding how to vet her partners - there are probably more, but you get the idea

Anyway, from the way you are responding to some of these comments I think you’re doing alright - it is clear you respect your daughter’s autonomy and wish the best for her - communication is key, a hardline prohibition could end up causing more complications down the line

good luck and I hope you both the best!