>>713080495
Lol, surely you jest. You can literally get a girl pregnant without even inserting your dick at all. Even a micropenis is usually at least 1 inch fully erect. That's more than enough to impregnate any women.
Now, if you want to instead focus on the likelihood of a man with a micropenis being infertile, then that's an entirely different argument which might actually be valid. The smaller the cock, the smaller the balls are in most cases. The smaller the balls, the higher the chance of infertility.