Screening of ultrasound markers for predicting selective fetal growth restriction in monochorionic twins at 11-13 + 6 weeks / 中华超声影像学杂志

ABSTRACT

Objective:To screen the ultrasound markers of predictive value at 11-13 + 6 weeks for selective fetal growth restriction (sFGR) in monochorionic (MC) twins. Methods:A retrospective analysis of MC twin pregnancies collected prospectively from June 2020 to December 2021 at Beijing Obstetrics and Gynecology Hospital, Capital Medical University, with standardized ultrasound examinations performed at 11-13 + 6 weeks.According to the expert consensus on the diagnostic criteria for sFGR, collected MC twin pregnancies were divided into sFGR group and control group (normal MC twin group). Maternal age, maternal history, mode of conception, the incidence of increased nuchal translucency (NT) thickness, NT discordance, crown-rump length (CRL) discordance, abnormal ductus venous Doppler waveform and abnormal umbilical cord insertion position were compared between the two groups, and those markers that differed between groups were further analyzed for screening early ultrasound markers that could be used to predict sFGR. Results:A total of 106 cases were included in the analysis, 30 cases in sFGR group and 76 cases in control group. ①Compared with control group, sFGR group had a higher incidence of low fetal birth weight (below the 10th and 3rd percentile) in both surviving cases, large birth weight discordance and a higher incidence of birth weight inconsistency (difference >25%) ( P<0.001). ②Compared with control group, the CRL discordance was larger in sFGR group [7.8% (3.8%, 9.2%) versus 3.8% (1.5%, 7.2%)] and the incidence of abnormal cord insertion position (33.3% versus 6.6%) was higher, the differences were statistically significant ( P=0.004 and <0.001, respectively), whereas the differences of NT discordance, incidence of increased NT and abnormal ductus venous Doppler waveform were not statistically significant (all P values >0.05). ③CRL discordance was a risk factor for sFGR ( OR=1.136, 95% CI=1.021-1.264), with an area under the ROC curve of 0.682 (95% CI=0.576-0.787) for predicting sFGR, the sensitivity and specificity were 0.567 and 0.737 at a cut-off value of 6.5%. Abnormal umbilical cord insertion position was a risk factor for sFGR ( OR=7.100, 95% CI=2.176-23.167) with a sensitivity of 0.333 and specificity of 0.934 for predicting sFGR. Conclusions:CRL discordance and abnormal cord insertion position are risk factors for the development of sFGR and are of value in predicting sFGR in MC twins.