Are you sure you didn’t mean “infinitely more horrifying?”

Not true, it’s all a crap-shoot.

A condom is at 99+%.

IIRC, having sex with an HIV positive person had a 100% risk of the HIV negative person contracting HIV, then if you looked at 100 women who have the ring, and 100 women who dont, 39 with the ring would contract the virus, where as 100 without would.