I already have premature ejaculation and I barely masturbate since I don't have high libido. I only do it like once every two months. I highly doubt masturbation promotes premature ejaculation. When I was younger, I'd masturbate WAY more and I didn't have premature ejaculation. It's more likely caused by anxiety and not having enough sex. The last girl I dated, we had sex twice a day for several days in a row. At first, I had premature ejaculation, but towards the end, I had full control. I think it just takes and getting into the swing of things, which would also reduce anxiety.