Associations of four insulin resistance indicators with subsequent pregnancy outcomes in women with recurrent pregnancy loss

Aims This study investigated the associations of four insulin resistance (IR) indicators—the triglyceride-glucose (TyG) index, the TyG-body mass index (TyG-BMI), the metabolic score for IR (METS-IR), and the triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio—with subsequent pregnancy outcomes in women with recurrent pregnancy loss (RPL) and assessed their predictive value. Methods This cohort study recruited RPL participants from the Chinese Pregnancy Loss Cohort. Enrollment occurred between September 2019 and December 2022. All participants were followed up every 6 months, with a minimum follow-up duration of 18 months, to document pregnancy outcomes (live birth or subsequent pregnancy loss). Univariate and multivariate logistic regression analyses were performed to assess the associations between four IR indicators (TG/HDL-C, TyG, TyG-BMI, METS-IR) and pregnancy outcomes. Receiver operating characteristic (ROC) analysis was conducted to determine the predictive efficacy of each indicator. Results Among 2,454 screened participants, 897 RPL women were analyzed (638 live births, 71.1%; 259 pregnancy losses, 28.9%). In the fully adjusted model, the highest tertiles of TyG-BMI and METS-IR were associated with significantly elevated odds of pregnancy loss (OR = 1.52, 95% CI: 1.01–2.27, P = 0.044; OR = 1.49, 95% CI: 1.05–2.29, P = 0.045, respectively). METS-IR demonstrated the highest predictive efficacy for pregnancy outcomes (AUC = 0.710), followed by TyG-BMI, TG/HDL-C, and the TyG index. Conclusions Among women with RPL, TyG-BMI and METS-IR are independently associated with increased pregnancy loss risk, with METS-IR demonstrating superior predictive performance.