Reference intervals for the cross sectional area of the umbilical cord during gestation.
OBJECTIVE
To establish reference values for the sonographic cross-sectional area of the umbilical cord during gestation and to correlate them with fetal anthropometric parameters.


METHODS
A cross-sectional study was performed involving 312 normal pregnant women at gestational ages 24-39 weeks. Measurement of the cross-sectional area of umbilical cord was performed on a plane adjacent to the insertion of the cord into fetal abdomen. The following anthropometric parameters were calculated: biparietal diameter, head circumference, abdominal circumference and femur length. A polynomial regression analysis identified the curves that were better adjusted to the average and standard deviation according to gestational age. Spearman correlation was used to evaluate the correlation of the cross-sectional area of umbilical cord with fetal anthropometric parameters.


RESULTS
A statistically significant correlation was observed between the cord cross-sectional area and gestational age (r=0.376, P<0.001, CI 95%[0.276; 0.467]).


CONCLUSIONS
The reference values of the cross-sectional area of umbilical cord increased according to gestational age until the 33rd week and are related to parameters of fetal growth.
Togni
Fernando Alves
FA
Department of Obstetrics, Sao Paulo's Federal University (Unifesp/EPM), Brazil.
Araujo Júnior
Edward
E
Moron
Antonio Fernandes
AF
Vasques
Flávio Augusto Prado
FA
Torloni
Maria Regina
MR
Nardozza
Luciano Marcondes Machado
LM
Guimarães Filho
Hélio Antonio
HA
D000293:Adolescent; D000328:Adult; D000886:Anthropometry; D003430:Cross-Sectional Studies; D005260:Female; D047109:Fetal Development; D006801:Humans; D011247:Pregnancy; D012015:Reference Standards; D014463:Ultrasonography; D014470:Umbilical Cord / Q000000981:diagnostic imaging*