Journal of Ultrasound in Medicine, Vol 15, Issue 8 585-593, Copyright © 1996 by American Institute of Ultrasound in Medicine
Placental cord insertion visualization with prenatal ultrasonography
D. H. Pretorius, C. Chau, D. M. Poeltler, A. Mendoza, V. A. Catanzarite and K. A. Hollenbach
Sharp Perinatal Center, Mary Birch Hospital for Women, San Diego, California, USA.
Color Doppler and gray scale sonography can be used prenatally to identify
the location of the cord insertion into the placenta. The purposes of this
paper were to (1) relate sonographic identification of placental cord
insertion with placental pathology; (2) evaluate the possibility that a
marginal cord insertion may evolve into a velamentous cord insertion; and
(3) determine the frequency and factors affecting sonographic visualization
of cord insertion. Our results show that the sonographic assessment of cord
insertion correlated with the pathologic outcome in 83% (106 of 128) of
singleton pregnancies and at least one of the fetuses in 72% (8 of 11) of
twin or triplet pregnancies. Although the sensitivity for identification of
an abnormal cord insertion was low (42%), the specificity was high (95%).
Our data suggest that marginal cord insertion evolved into velamentous cord
insertion in one singleton and one twin. Our results showed that cord
insertion was visualized in 54% of fetuses scanned in a routine clinical
practice. Cord insertion visualization was possible at all gestational
ages, although it was more difficult at later gestational ages. In
conclusion, this study provides evidence that (1) ultrasonography (either
gray scale or color Doppler) is useful in identifying normal, marginal, and
velamentous cord insertion; (2) marginal cord insertion may evolve into
velamentous cord insertion as pregnancy progresses; (3) in clinical
practice the cord insertion site was visualized in just over half of the
cases, and (4) prenatal identification of marginal and velamentous cord
insertion potentially may be useful for planning obstetrical management.
