Clinical Estimation of Fetal Weight: An Evaluation of Accuracy and Predictive Value

Abstract

Objective: To determine the diagnostic accuracy of clinical method in estimating fetal weight at term by
taking actual birth weight as reference standard.
Material and Method: This was a cross sectional validation study, conducted in the Department of Obstetrics
& Gynaecology, Central Park hospital, between February 2024 to July 2024. Consecutive non-probability
sampling technique was used to include term pregnancies after inclusion and exclusion criteria. Demographic
profile including age, parity, duration of pregnancy was recorded. Dare's formula was applied for estimation
of fetal weight clinically. All data was entered in SPSS version 26 for analysis. A 2x2 table was used to calculate
sensitivity, specificity, positive predictive value, negative predictive value and accuracy.
Results: Total 225 patients with term pregnancy were included in study. Mean age of patients was 31.44 years
with standard deviation of 5.573. Mean gestational age was 37.88 + 0.687 weeks. Mean clinical fetal weight
was 2947.55 grams with Standard deviation of 502.232. Mean actual fetal weight was 2978.22 grams with
Standard deviation of 506.314. Clinical estimation of fetal weight had sensitivity of 85.3% and specificity of
81.8% in predicting fetal birth weight. Positive predictive value was 93.5% and negative predictive value was
64.3%.
Conclusion: Clinical fetal weight estimation was near to accuracy in pregnant women with normal fetal
weight ranges. However, the clinical estimation was significantly low in cases of fetal weight less than 2.5 kg
and more than 4 kgs.
Keywords: Actual birth weight, Term Pregnancy, Clinical estimation of fetal weight.