IVF requires a lot more work than that. First the egg donor would take fertility drugs in order to drop several ova at once for harvest. Then the ova would be fertilized in test tubes and allowed to divide for some time before being implanted into the recipient to hopefully implant themselves into the uterine wall and begin growing. Multiple embryos are implanted in the hopes that at least one will take and each round costs upwards of $20k dollars in the U.S. Not to mention that any reputable fertility doctor would not use donor eggs from the sister of the prospective father

Though ketzal's facepalm indicates I may have misinterpreted what was going on in that scene.