Gestational age:Time:Pt:^Fetus:Qn:US+Estimated from BPD.Doubilet 1993
gestational age:time:pt:^fetus:qn:us+estimated from bpd.doubilet 1993
Gestational age estimated from Biparietal diameter on US by Doubilet 1993 method
gestational age estimated from biparietal diameter on us by doubilet 1993 method