I'm certainly not an expert, but I read once that if you are trying to conceive, the man should have sex with you every other day. If the man ejaculates much more than that, then there might not be much sperm in the semen.

I'm no expert either, but people make up lies. It doesn't effect you when you're having sex. But try to let sperm produce, so dont mastorbait for 1-3 days.

It depends on his sperm count. If he's got a low sperm count it will most definitely affect his fertility. For most healthy men, ejaculation once a day during the woman's fertile period is ok. If there are any doubt, ejaculation every two days are better.

During your non-fertile weeks, he can ejaculate as many times as he wants without affecting his performance when it counts.