Which sFGR Diagnostic Criteria Predict Better Outcomes?

Clinicians often struggle to choose the best sFGR diagnostic criteria for monochorionic twin pregnancies. Therefore, a recent study compared the ISUOG and Delphi definitions to evaluate their predictive power. The researchers analyzed 363 monochorionic diamniotic twin pregnancies over a 24-year period. Specifically, the study found that the Delphi consensus definition identifies more cases of selective fetal growth restriction.

Comparing sFGR Diagnostic Criteria: Delphi vs ISUOG

The Delphi definition diagnosed 30.3% of the cohort, while the ISUOG criteria identified only 14.6%. However, the additional cases found only by Delphi criteria showed better overall outcomes. These twins had significantly lower neonatal morbidity and higher survival rates. Consequently, the ISUOG criteria remain more specific for identifying the highest-risk pregnancies. Each component of the Delphi definition independently links to reduced intact survival.

Predictive Value of sFGR Diagnostic Criteria

Moreover, all combinations showed only low-to-moderate ability to predict twin demise. The Delphi criteria demonstrated slightly higher sensitivity than ISUOG for predicting the death of the smaller twin. In contrast, the ISUOG definition offered higher specificity for these outcomes. These findings suggest that while Delphi catches more cases, ISUOG is more precise for severe outcomes. Additionally, each constituent criterion in the Delphi definition associated independently with adverse outcomes. Furthermore, clinicians must still determine the most appropriate tools for diagnosing these complex pregnancies.

Frequently Asked Questions

Q1: Which definition is more sensitive for detecting sFGR?

The Delphi consensus definition has a higher detection rate and higher sensitivity for predicting the demise of the smaller twin compared to ISUOG criteria.

Q2: Should clinicians rely solely on the Delphi criteria?

While Delphi criteria catch more cases, the ISUOG definition is more specific for identifying cases with high perinatal morbidity and mortality.

Q3: How does the Delphi definition impact survival predictions?

The study showed that each individual criterion within the Delphi definition independently associates with a reduction in the intact survival of both twins.

References

1. Sorrenti S et al. Perinatal outcome of monochorionic twin pregnancy complicated by selective fetal growth restriction: ISUOG vs Delphi diagnostic criteria. Ultrasound Obstet Gynecol. 2026 May 13. doi: 10.1002/uog.70239. PMID: 42126513.
2. Khalil A et al. Consensus definition and diagnostic criteria for selective fetal growth restriction in monochorionic twin pregnancies: a Delphi procedure. Ultrasound Obstet Gynecol. 2019 Jan;53(1):47-54. doi: 10.1002/uog.19013.
3. International Society of Ultrasound in Obstetrics and Gynecology. ISUOG Practice Guidelines: role of ultrasound in twin pregnancy. Ultrasound Obstet Gynecol. 2016 Feb;47(2):247-63. doi: 10.1002/uog.15821.