Use of colon caliber diameter as auxiliary method in pregnancy dating between 34-40 weeks of gestation

Abstract

Objective: to verify whether fetal colon caliber correlate with gestational age from 34 to 40 weeks of gestation and to develop equation and chart which can be used for pregnancy dating by measuring colon caliber. Methods: a total of 220 healthy pregnant women whose age range from 18- 35 years were collected. They were distributed as 30 patients for each of the following gestational ages 34, 35, 36,37,38,39 weeks and 40 patients for 40 weeks of gestation. Their head circumference, abdominal circumference, bi-parietal diameter and femoral lengths were assessed by ultrasound. In addition colon caliber was assessed in the transverse colon. Result: there was a highly significant correlation between colon caliber and gestational age in days. In addition a highly significant correlation between colon caliber and bi-parietal diameter, femoral length, head circumference and abdominal circumference were found with P values < 0.0001. A formula was developed to calculate gestational age directly from the fetal colon caliber alone. The equation accuracy was checked by Kappa- Cohen coefficient and found to be 0.71 indicating good predicative ability of this formula. Conclusions: despite a new easy to use formula and associated easy to use chart was developed yet we call for extreme caution in its use as we don’t know its significance in real life obstetrical world. Further studies are required to confirm its reliability and safety