I was never told all through college about the pill-and-antibiotics thing. As it turns out, my uterus is about as fertile as a concrete sidewalk and I likely can't get pregnant without medical intervention but it would have been nice to know all those years I thought I was protected.
Sex ed in my high school (we got one hour of it, for one day, during 10th grade. I was already sexually active by then). Our biology teacher was 8 months pregnant but the lesson was almost right out of mean girls: only bad, sl#tty girls have sex before marriage.
I was also told that there are small holes in the condoms that are too small for sperm to get through but the HIV virus bits (whatever they're called) fit right through them so if you have sex with someone with HIV while wearing a condom, you are getting concentrated HIV. We girls were scowled at and basically told to stay virgins and that we should fear the penis.
This was in the late 1990s and I'm still amazed we didn't have more teen pregnancies.
On topic - I have not (yet) been pregnant and have never heard of the heavy bleed post-birth. Makes sense but as with everything else related to my reproduction, I was not informed at school and have had to learn via movies, TV, and Wikipedia/google. Anything I can't get at that point gets referred to the Doc-lady.