Impact of doppler reference chart selection on risk stratification in fetal growth restriction.

BACKGROUND

Doppler studies play a crucial role in evaluating fetuses with impaired fetal growth.

OBJECTIVE

We aimed to assess the clinical variability of various published Doppler reference ranges for umbilical artery (UA) pulsatility index (PI), middle cerebral artery (MCA) PI, and cerebroplacental ratio (CPR) in pregnancies complicated by impaired fetal growth, and their association with adverse perinatal outcomes. STUDY

DESIGN

This retrospective cohort study included all singleton pregnancies with estimated fetal weight (EFW) and/or abdominal circumference (AC) below the 10th percentile for gestational age (2017-2022). Eligible cases had a concurrent sampling of UA-PI, MCA-PI, and CPR within 14 days of birth. Abnormal fetal Doppler was defined using clinically relevant cut-offs for gestational age: UA-PI > 95th percentile, MCA-PI < 5th percentile, and CPR < 5th percentile. The primary outcome was a composite of adverse perinatal outcomes The association between published Doppler thresholds and adverse perinatal was assessed using univariate and multivariable logistic regression analyses.

RESULTS

The cohort included 947 patients, of whom 438 (46.3%) experienced adverse perinatal outcomes, while 509 (53.7%) had normal outcomes. The predictive performance for adverse perinatal outcomes of various published Doppler reference values showed variability. Sensitivity ranged from 58.5% to 67.4% for UA-PI, 55.4% to 61.4% for MCA-PI, and 52.1% to 58.8% for CPR. Corresponding specificities ranged from 56.0% to 60.0%, 58.0% to 60.7%, and 61.4% to 61.9%, respectively. After multivariate analysis, which controlled for relevant covariates, strong associations were demonstrated between abnormal UA-PI, MCA-PI, and CPR Dopplers and adverse perinatal outcomes in preterm deliveries. Baschat’s reference chart for CPR was the only one that was found to have an association with adverse perinatal outcomes in term pregnancies.

CONCLUSION

Choosing a Doppler reference chart may result in significant variation in the clinical management of pregnancies complicated by impaired fetal growth.