It’s not like there are people checking for immortals, I think it would be flagged by a dmv employee or something when they dont believe a clear 21 year old is actually 150. Let’s assume it’s current day im caught and not bring speculation on what the US is like in the year 2139 is like.
But you would need to check VERY closely who you are having children with.
That 21 year old you are putting a bun in the oven might be your granddaughter.
That would be immoral,even on a highlander scale.