Prenat Diagn. 2025 Aug 16. doi: 10.1002/pd.6873. Online ahead of print.
ABSTRACT
OBJECTIVE: To evaluate the diagnostic accuracy of sonographic estimated fetal weight discordance (EFWD) ≥ 20% in predicting birthweight discordance (BWD) ≥ 20% (i.e., selective fetal growth restriction [sFGR]) in monochorionic (MC) twin pregnancies.
METHOD: Retrospective cohort study including uncomplicated MC twin pairs (n = 213) and MC twins with sFGR (n = 134), with available ultrasound within 14 days of birth approximately 2002 and 2023 in our center. Within 14 and 7 days of birth, we calculated sensitivity and specificity. In a subgroup of twins with available ultrasound within 3 days of birth, the absolute error of BWD was calculated (BWD-EFWD).
RESULTS: The sensitivity and specificity of EFWD ≥ 20% within 14 days of birth in predicting BWD ≥ 20% were 84% (95% CI 76-89) and 85% (95% CI 79-89), respectively. Ultrasounds available within 7 days of birth (n = 192/347) showed comparable diagnostic accuracies (sensitivity 85% [95% CI 75-92], and specificity 81% [95% CI 73-88]). Among twins with available ultrasound within 3 days of birth (n = 90/347), the absolute error of BWD was -2.0% (SD 8.0), indicating a mean overestimation of BWD.
CONCLUSION: In MC twins with sFGR, the accuracy of sonographic EFWD ≥ 20% in predicting BWD ≥ 20%, is relatively high. BWD is overestimated by an average of two percentage points within 3 days of birth.
PMID:40818062 | DOI:10.1002/pd.6873