Journal of Ultrasound in Medicine, Vol 12, Issue 9 513-515, Copyright © 1993 by American Institute of Ultrasound in Medicine
Proximal humeral ossification center of the fetus: time of appearance and the sensitivity and specificity of this finding
A. C. Nazario, C. I. Tanaka and N. F. Novo
Escola Paulista de Medicina, Sao Paulo, Brazil.
Ultrasonographic examinations were performed on 1,000 pregnant women
between the 28th and 40th weeks of gestation who had been seen at a private
clinic. For all women the date of last menstruation was known, and none had
obstetrical or clinical-surgical complications. All were singleton
pregnancies, and cases of fetal malformation were excluded from the study.
The proximal humeral epiphyseal ossification center was visualized
significantly frequently after the 38th week (P < 0.001). With respect
to a gestational age of more than 38 weeks, its specificity was elevated
(99%), as also were its positive (91%) and negative (93%) predictive
values. Its sensitivity, however, was low (58%). Routine determination of
the proximal humeral ossification center is a valuable aid for the
estimation of gestational age in the third trimester.
