Accuracy of Ultrasonographically Measured Placental Thickness in Third Trimester for Estimation of Gestational Age: A Cross Sectional Study Among Indian Population

Exact determination of gestational age is of great clinical importance to the Obstetricians, dilemma remains in those women having unreliable LMP or having no early dating scans. A cross sectional study was done on 202 antenatal women in the third trimester (29 - 40 weeks), to evaluate the accuracy of ultrasonographically measured placental thickness in the third trimester for the estimation of gestational age in normal singleton pregnancies. It was found that Placental thickness gradually increased and corresponded with period of gestation from 29 to 38 weeks and then either it was constant or 1-2 mm lower than the period of gestation. Placental thickness is an effective ultrasonographic parameter for estimation of gestational age.