The relationship between insulin resistance and recurrent pregnancy loss in assisted reproductive technology: A retrospective case-control study

This study aimed to investigate the association between insulin resistance (IR) and recurrent pregnancy loss (RPL) in patients undergoing assisted reproductive technology (ART). A retrospective analysis compared glucose and insulin indices (including fasting insulin [FINS], Homeostatic Model Assessment for Insulin Resistance [HOMA-IR], Homeostatic Model Assessment for Beta-Cell Function [HOMA-β], and area under the curve for insulin [AUCI] between RPL (n = 279) and non-RPL (n = 246) groups. Adjusted logistic regression models evaluated the correlation between IR-related indices and RPL risk. Compared with the non-RPL group, the RPL group exhibited significantly higher levels of FINS (10.67 vs. 8.57; P < .001), 1-hour insulin (1hINS) (110.86 vs. 74.75; P = .005), 2-hour insulin (2hINS) (89.47 vs. 67.94, P = .023), AUCI (117.08 vs. 114.16; P = .004), HOMA-IR (2.5 vs. 1.94; P < .001), HOMA-β (138.31 vs. 107.84; P < .001), the incidence of insulin resistance (63.47% vs. 47.03%; P < .001), and the incidence of HOMA-IR ≥ 2.14 (61.9% vs. 40.27%; P < .001). After adjusting for other factors, patients with IR had a higher risk of developing RPL compared with those without IR, with an odds ratio (OR) of 1.87 (95% CI: 1.18-2.94). Furthermore, an increase in FINS, HOMA-IR, and HOMA-β was associated with a significantly higher incidence of RPL, with OR values (95% CI) of 1.07 (1.03-1.12), 1.23 (1.03-1.48), and 1.01 (1.0-1.01), respectively. IR is an independent risk factor for RPL in ART patients, emphasizing the need for pretreatment interventions (e.g., lifestyle modifications or metformin) to improve insulin sensitivity and reduce miscarriage risk.