The crown-rump length in early human pregnancy: a reappraisal.
The crown-rump length (CRL) was measured by means of transvaginal sonography in 41 pregnancies resulting from in-vitro fertilization (IVF). The embryonic CRL could be determined as early as 25 days after follicle aspiration. A reference chart was constructed relating the CRL to the number of days following follicle aspiration. Comparison with the CRL chart by Robinson & Fleming (1975) currently in use revealed that transvaginal sonography allows earlier and more accurate measurement of embryonic CRL.
Schats
R
R
Department of VEVO/IVF, Academisch Ziekenhuis Vrije Universiteit, Amsterdam, The Netherlands.
Van Os
H C
HC
Jansen
C A
CA
Wladimiroff
J W
JW
D000328:Adult; D000886:Anthropometry; D005314:Embryonic and Fetal Development; D005260:Female; D005307:Fertilization in Vitro; D005333:Fetus / Q000033:anatomy & histology*; D006801:Humans; D015588:Observer Variation; D011247:Pregnancy; D012016:Reference Values; D013997:Time Factors; D016216:Ultrasonography, Prenatal / Q000379:methods / Q000592:standards*; D014621:Vagina