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Guide Wire Assisted Catheterization and Colored Dye Injection for Vascular Mapping of Monochorionic Twin Placentas
Published on: September 5, 2011
Sonographic evaluation of umbilical cord insertion with umbilical coiling index
Y Otsubo1, Y Yoneyama, S Suzuki
1Department of Obstetrics and Gynecology, Nippon Medical School, Tokyo, Japan.
Purpose:
The aim of this study was to investigate the association between umbilical cord hypocoiling and abnormal placental insertion of the umbilical cord.
Methods:
Umbilical coiling was measured by sonography in 253 pregnant women in their second or third trimester. An umbilical coiling index, defined here as the reciprocal of the length of 1 umbilical vascular coil, of less than 0.1 was considered hypocoiled. The distance from the placental edge to the insertion of the umbilical cord was measured after delivery, and the results were used to classify cord insertion as normal, marginal, or velamentous.
Results:
Cord insertion was abnormal in 66.7% of the fetuses with umbilical hypocoiling but in only 1.3% of those whose coiling index was > or = 0.1 (p < 0.05).
Conclusions:
Hypocoiling of the umbilical cord was highly associated with abnormal cord insertion. The presence of a hypocoiled umbilical cord may indicate the presence of abnormal cord insertion and thus may be useful for obstetric management.

