Module 1 - GAP Theory
Module 2 - GAP Practice

1.4 LBW, SGA, and FGR (3/3)

Regardless of the limit chosen, any group of SGA fetuses or babies include those that are physiologically / constitutionally small, and those that are pathologically small, i.e. growth restricted.

Customising the standard adjusts for constitutional variation, improves identification of pathological smallness (FGR), and reduces false positive diagnoses. 1  4 5


1. Clausson B, Gardosi J, Francis A, Cnattingius S. Perinatal outcome in SGA births defined by customised versus population-based birthweight standards. 
Br J Obstet Gynaecol. 2001;108(8):830–834. https://doi.org/10.1111/j.1471-0528.2001.00205.x

4. Figueras F, Figueras J, Meler E, et al. Customized birthweight standards accurately predict perinatal morbidity.
Arch Dis Child Fetal Neonatal Ed 2007;92:F277-80

5. McCowan LM, Harding JE, Stewart AW. Customized birthweight centiles predict SGA pregnancies with perinatal morbidity.
BJOG 2005;112:1026-33