I think 50 is too to fatherold because of the risks of schizophrenia, autism, breast cancer, prostate cancer, etc. in the child. Of course there is a greater chance of a normal child but read the literature on an older father's affect on the health of especially daughters. Good luck in what you choose. I don't want to alarm but I speak from experience. Sperm donation is limited in some cases to 35, 37, 38, 0r 40 because of genetic risks.