Predicting the risk of fetal distress in premature infants with intrauterine umbilical cord torsion: development and assessment of a new predictive nomogram

Abstract Purpures: This study intends to establish a clinical prediction model of intrauterine distress in premature infants with intrauterine umbilical cord torsion. Methods: The clinical data of umbilical cord torsion induced by prenatal ultrasound in the third trimester of pregnancy in Beijing Obstetrics and Gynecology Hospital from September 2017 to September 2021 were retrospectively analyzed. Besides, the prediction model was developed and verified according to time. Taking fetal distress as the final variable, 13 predictive factors were selected for modeling. In the development group, the final predictors were selected into the final model by Lasso and multi-factor logistic regression, and the calibration, discrimination and Decision Curve Analysis (DCA) of the final model were evaluated. The final model was verified again by using the verification group data, and the stability of the final model was evaluated. Results: A total of 182 patients met the inclusion criteria from September 2017 to September 2021. 154 cases from September 2017 to September 2020 were divided into the development group and 28 cases from October 2020 to September 2021 were divided into the verification group. Except for the difference of infection factors during pregnancy between the two groups, there was no significant difference in other indexes (P < 0.05). After the development group was screened by Lasso and multi-factor logistic regression, the final five indexes were included in the final model. The model showed good calibration and differentiation, Area Under Curve (AUC) was 0.783, sensitivity was 65.2%, and specificity was 83.5%. External verification using verification group data showed that the model also had good calibration and differentiation. DCA showed that when the prediction model was within the 6-88% threshold, the model was effective in clinical application. Conclusion: For premature infants with umbilical cord torsion, this model can more easily evaluate the risk of fetal distress in uterus through the combination of clinical and ultrasonic indexes, so as to help clinical intervention and ensure maternal and infant safety.