Elyz1214 is right about the geneticist! They could answer your questions a lot better. however. Everybaby measured in the womb usually is off. Like for instance, with my daught they said she was going to come out at 23" long, (from their measurements) and she would be over 7lbs.. She was 18" and 5 lbs 2oz.. My son, measured 4 weeks ahead they had once again told me he would come out at 22" - 25", and he was 19 inches... They said he was going to be 9 ish lbs, and he was 5lbs 12 oz. The measurements on there for their legs and arms, is a guess.
A baby can be with in a 1 lb either way up or lower, and same with heigth. About the only thing they can forsure get pretty accurate it the head circumfrance, and the stomach size! My kids had bigs heads and bigger tummy's!
And my mom is 4 ft 9 and my dad is 6ft 1... I'm 5'6" suppose to be 5"8 ( I hit a growth plate when I broke my legs when I was younger, stunted my own growth!
Everyone is my family is taller than my mom. Same with my husbands family, everyone is taller then their mom and their mom is I think 5 ft..
this is something a geneticist would be able to help you with a WHOLE lot better than us preggo moms! 5'11" isn't short and HGH shots hurt like heck.
There is a medical ethics debate about them anyway - make sure you do plenty of research, and just because your child may have shorter bones in utero doesn't really mean anything - babies and kids grow so intermittently.
I'm 5'9" and my son's dad is 6'9" but my 9 year old son is still wearing size 6 clothes he's so small - I'm not the least bit worried, he'll catch up sooner or later I reckon - and if not - I don't really care.