#57 : A Prediction Model of Low Birthweight in Singleton Pregnancies Reduced from Dichorionic Twin Pregnancies

Abstract

Background and Aims: The incidence of twin pregnancies has risen over the last few decades, mainly attributed to assisted reproduction techniques (ART). Fetal reduction (FR) can significantly reduce low birthweight (LBW) risk in twins. However, the LBW risk is still higher in singletons reduced from twins than for primary singletons. Many factors, such as maternal factors, FR timing and approach may affect LBW risks after FR and no relevant prediction models have been reported to date. The main objective of this study is to develop a nomogram to predict LBW risk in singleton pregnancies reduced from dichorionic (DC) twins. Method: We retrospectively reviewed and analyzed the data on women with (DC) twin pregnancies who underwent FR in Women’s Hospital, Zhejiang university, School of medicine in July 2005 to August 2021. Logistic LASSO regression was used to identify the most relevant variables associated with LBW. The nomogram was constructed and receiver operating characteristic (ROC) curve, Hosmer-Lemeshow test, and decision clinical analysis were used for model performances assessment and visualization. The model was evaluated by cohorts produced by 500 resampling bootstrap analysis to testify the stability. Results: A total of 471 patients were enrolled in the analysis. At last, seven independent predictive factors for LBW were identified and integrated to construct the nomograms, including maternal height, nulliparous, conception mode, reasons for FR, gestational age at FR, gestational diabetes, pregnancy hypertensive disease. The AUC of our prediction model was 0.793, which was validated by internal (AUC 0.762) confirmation with bootstrap analysis. The nomogram had well-fitted calibration curves. Decision curve analysis demonstrated that the nomogram was clinically useful. Conclusion: We made the first attempt to develop a reliable predictive nomogram for the risk of LBW in DC twin pregnancies reduced to singletons, providing a useful guide for clinicians and patients in making appropriate FR decisions.