Gestational age:Time:Pt:^Fetus:Qn:US+Estimated from HL.Merz 1987
gestational age:time:pt:^fetus:qn:us+estimated from hl.merz 1987
Gestational age estimated from Humerus length on US by Merz 1987 method
gestational age estimated from humerus length on us by merz 1987 method