Local References for Ultrasound-Estimated Fetal Weight Based on 2,211 Singleton Pregnancies in the City of Curitiba, South of Brazil - Revista Brasileira de Ginecologia e Obstetrícia

Abstract

Objective

To develop reference curves of estimated fetal weight for a local population in Curitiba, South of Brazil, and compare them with the curves established for other populations.

Methods

An observational, cross-sectional, retrospective study was conducted. A reference model for estimated fetal weight was developed using a local sample of 2,211 singleton pregnancies with low risk of growth disorders and well-defined gestational age. This model was compared graphically with the Hadlock and Intergrowth 21^st curves.

Results

Reference curves for estimated fetal weight were developed for a local population. The coefficient of determination was R² = 99.11%, indicating that 99.11% of the fetal weight variations were explained by the model. Compared with Hadlock curves, the 50^th, 90^th, and 97^th percentiles in this model were lower, whereas the 10^th percentile nearly overlapped, and the 3^rd percentile was slightly higher in the proposed model. The percentiles were higher in the proposed model compared with the Intergrowth 21^st curves, particularly for the 3^rd, 10^th, and 50^th percentiles.

Conclusion

We provide a local reference curve for estimated fetal weight. The proposed model was different from other models, and these differences might be due to the use of different populations for model construction.