I imagine that the egg from one male partner would then fertilised in vitro with sperm from the other male partner... i.e. what used to be characterised as "a test tube baby". Presumably the fertilised egg would then be implanted into a uterus, so we're looking at a form of surrogacy, which can also be controversial, and is banned even in some European countries, e.g. France, Germany, Italy, Spain, Portugal and Bulgaria. So there are clearly a whole host of complex, ethical issues, which I don't pretend to have an answer to. Nevertheless, the concept leaves me feeling rather uneasy, in particular as regards the emotional implications for the child.