Does jacking off affect

Sperm count when TTC?  My husband and I have an extremely healthy sex life. We usually have sex 5-7 days a week. Sometimes when he's home alone he like to masturbate. Which I'm totally okay with. But I heard it decreases sperm count.. Is it bad for him to masturbate and then we have sex later that night while ovulating? Or is it best he holds off? He's fine with not doing it, if I ask him. Just curious. Thanks