In the U.S.A. "NT" or non-autistic girls usually lost their virginity well before 18 -- ~15 on average in today's "climate."
If autistic or etc. maybe 21+ or -- even if super-rarely -- never. This means lose virginity AKA fuck a guy, not rug munching escapades.
Doesn't matter though since their "femceldom" is virtually 100% a choice 99% of the time, lest she's extremely socially done for which is RARE.
Also, reminder that 15-16 is "average" for intercourse -- this doesn't mean loads of girls under it haven't already had some sort of "experience."