“…E-mail: manuelarteagamartinez@yahoo.com Among the consequences of wide-spread use of fetal echocardiography has been the realization that to obtain an accurate diagnosis, through clear differentiation between normal heart and congenital heart disease, the morphometric dimensions of the different segments of the human heart must be known precisely (Fyfe and Kline, 1990). Presently, there are only a few morphologically based studies supporting the use of fetal echocardiography and most of these have been carried out in evaluations of patients suffering from congenital cardiopathies (Allan et al, 1980(Allan et al, , 1984(Allan et al, , 1997Lapasset et al, 1986;Paladini et al, 1990;Sun et al, 1999;Kirk et al, 1999). Although there is little doubt that the echocardiogram used as a diagnostic test has good sensitivity to detect congenital malformations, neither its specificity nor its predictive value, have been fully analyzed and described.…”