Third-Trimester Cerebroplacental Ratio and Preceding Fetal Growth in Appropriate-for-Gestational-Age Fetuses: Limited Individual-Level Information in a Longitudinal Cohort

Background/Objectives: Cerebroplacental ratio (CPR) is mainly a contemporaneous hemodynamic and prognostic marker but has also been proposed as a marker of impaired growth velocity. We quantified how much third-trimester CPR constrains an individual fetus’s preceding measured growth.

Methods

In a retrospective single-center cohort, conditional estimated fetal weight growth (cEFW) was derived in 920 singleton pregnancies and analyzed in 760 fetuses appropriate for gestational age (AGA) at the third-trimester scan (median 32.9 weeks), with umbilical and middle cerebral artery Doppler measurements obtained during the same examination. Quantile regression estimated the conditional/unconditional 10th–90th percentile width of cEFW (width ratio) by within-cohort CPR z-score.