I have asked probably 100 adults in roughly my age range if, as teenagers, their parents ever talked to them about sex and literally only one person has ever said yes.
@codinghorror My parents used the cop out of this book series called "A Doctor Talks to an X Year Old". It started here, I think:
https://www.ebay.com/itm/265814238966
It was OK in a dry, emotionally distant way.