Study of Estimation of Gestational Age by Ultrasonography using Fetal Parameters at a Tertiary Institute

Abstract

Background: Accurate estimation of gestational age (GA) is essential for proper prenatal care, early detection of growth abnormalities, and planning for delivery. Ultrasonography (USG) has become the gold standard for assessing GA, especially when the last menstrual period (LMP) is uncertain or unavailable. Fetal parameters like crown-rump length (CRL), biparietal diameter (BPD), femur length (FL), and abdominal circumference (AC) are commonly used in ultrasound to estimate GA.

Objective: The primary aim of this study is to evaluate the accuracy of gestational age estimation using various fetal parameters measured via ultrasonography at a tertiary care institute.

Methods: This cross-sectional study was conducted on pregnant women who presented for routine obstetric ultrasound. The gestational age was estimated using CRL, BPD, FL, and AC, and compared with the GA based on the LMP or the gold standard of neonatal birth weight.

Results: A total of 200 women were included in the study. The results showed that BPD and AC were the most reliable parameters for GA estimation in the second trimester, with a mean error of ±2.3 weeks.

Keywords: Gestational age, Ultrasonography, Fetal parameters, Biparietal diameter, Crown-rump length, Abdominal circumference, Femur length, Tertiary care institute.