Gestational age:Time:Pt:^Fetus:Qn:US+Estimated from GSL.Hansmann 1979
gestational age:time:pt:^fetus:qn:us+estimated from gsl.hansmann 1979
Gestational age estimated from Gestational sac length on US by Hansmann 1979 method
gestational age estimated from gestational sac length on us by hansmann 1979 method