WHat's in soy that so powerfully affects sex hormones?

I’m reading that one explanation (untested theory?) used to explain early menarche is use of infant formula containing soy - clearly an epidemiological study - a correlational inference. I also recently read that one tentative explanation for lowered sperm count is a diet high in soy. What gives?

Soy contains phytoestrogens/ plant estrogens. Here’s some general info, not intenteded to support or contradict the health claims.

Yes, that seems to be the ticket. Verrrrry intereshting. Not schtupid.