I read this in a magazine recently. You can get a sense of your baby’s future height based on the heights of the two biological parents. For boys, add 5 inches to mom’s height. Your son will be between that height and his daddy’s height. For girls, subtract 5 inches from her dad’s height. Your daughter will be between that height and mama’s height.
In my case this is not a helpful predictor at all because with a 13 inch height difference between me and my husband, we still end up with a 7-inch range for a prediction. At least I know my son will be taller than me. Maybe it calculates more precisely for you.