I think 4 but i was still sore and couldn't til week 6. Also i don't think that's the most fertile for all women. My Husband and i didn't use any protection for over a year and i didn't get pregnant. and trust me we had sex at least every other day It all depends on your body and hormones.
I went 5 I was so hurt wasn't even thinking of sex
Lots of women have sex before then which is what I am referring to. I know the recommended wait time is 6 weeks. I'm also aware many do not wait that long
You shouldnt have sex til your doctor gives the okay, which is usually at your 6 week check up. And just a FYI, you are super fertile those few weeks after giving birth.