1 Introduction
Fetal growth restriction (FGR), traditionally defined as estimated fetal
weight <10th percentile, is a leading risk factor for stillbirth
and a major focus of antenatal ultrasound use.(1) Current diagnostic
strategies for FGR perform poorly to predict perinatal morbidity and
mortality, such that most fetuses diagnosed with FGR do not experience
any perinatal morbidity.(2) Efforts have been made to customize fetal
growth assessments using maternal and fetal factors that are associated
with variation in fetal growth, including maternal race.(3) However,
race is a socially defined construct that is fluid over time and subject
to considerable admixture and therefore is a problematic proxy for
genetic growth potential.(4) Furthermore, its use has the potential to
exacerbate disparities by conflating the effect of imposed deprivations
with genetics, potentially reclassifying abnormal growth as normal and
causing necessary surveillance and interventions to be withheld.(5, 6)
Instead, the integration of genetic data may be a more valid and
effective approach to personalize fetal growth assessments and thereby
improve recognition of abnormal growth. Recent studies identified
genetic markers associated with fetal growth that could be used for such
purposes.(7-9) However, it is increasingly recognized that genetic
findings in predominantly European cohorts do not generalize to more
diverse populations.(10-12) Therefore, the objective of this study was
to assess a genetic risk score (GRS) for birth weight
(GRSBW), recently developed from a European cohort, for
generalizability within groups defined by self-identified race and
genetically predicted ancestry.
Because the rationale to use a GRSBW to customize fetal
growth assessment is to obviate the impulse to customize using
race/ethnicity, our secondary objective was to determine whether
self-identified race/ethnicity remains associated with birth weight (BW)
after accounting for the GRSBW.