Objective To investigate the predictive value of twins’growth and development discrepancy in prenatal ultrasound diagnosis of twin reversed arterial perfusion sequence (TRAPS) in the first trimester of pregnancy at 8-11 weeks of pregnancy. Methods From May 2001 to August 2021

the prenatal ultrasound diagnosis of Hubei Province Maternal and Child Health Hospital and the diagnosis confirmed by post-induction or post-natal pathology were collected 153 Cases of TRAPS

37 cases of prenatal ultrasound examinations at 8-11 weeks of gestation were retrospectively analyzed

and 42 cases of monochorionic twin pregnancies in early pregnancy with no obvious structural abnormalities in prenatal ultrasound system examination and postpartum follow-up were collected as the control group. Summarized the ultrasound characteristics and counted the difference in the number of days corresponding to the gestational week size of the two fetuses in the first trimester and the difference in embryo length separately

and the receiver operating curve (ROC) was used to evaluate the predictive value of TRAPS in the first trimester. Results 1. Among 37 cases of TRAPS

36 cases were twin pregnancy

1 case was triple pregnancy

42 cases in normal group were twin pregnancy. 2. 37 cases of TRAPPS in the larger embryos were visible normal cardiac throbbing

34 cases of smaller embryos did not see obvious cardiac throbbing

3 cases of visible cardiac throbbing

42 cases of control group double fetuses were visible normal heart tube throbbing.3 .There was no significant difference in the age of the two groups of patients and the clinical gestational weeks of the two fetuses (P>0.05); the difference in ultrasound gestational weeks between the two fetuses in the study group and the control group was 9.1±6.9 days and 1.6±1.5 days

respectively. The results of the two groups were statistically different (P<0.05); the difference in embryo length between the study group and the control group was 10.3±7.7mm and 1.9±1.9mm

respectively

and the results of the two groups were statistically different (P<0.05). 4. Using the receiver operating curve (ROC) analysis

when the difference between two embryos is more than 5 days and the length of two embryos is more than 4.5 mm as the cut-off value for diagnosis of TRAPS

the area under the curve

sensitivity

specificity

the positive predictive value and negative predictive value were 0.65 vs 0.66

67.6% vs 75.7%

97.6% vs 97.5%

92.3% vs 87.8%

and 77.3% vs 82.2%

respectively. Conclusion The uncoordinated growth and development of twin fetuses and the absence of significant cardiac throbbing in one of the embryos were of high value to predict the occurrence of TRAPS during 8-11 weeks of early pregnancy.