Association of HOMA-IR with unexpected poor ovarian response in non-obese women in poseidon 1: a retrospective cohort study.

Background: Insulin resistance (IR) is related with adverse outcomes of in vitro fertilization (IVF) in women with obesity, but little is known about the relationship between IR and unexpected poor ovarian response (uPOR) in non-obese subjects with sufficient ovarian parameters (classified as POSEIDON group 1). This research aims to explore the association between the homeostasis model assessment of insulin resistance (HOMA-IR) and uPOR in non-obese women with normal biomarkers of ovarian reserve.

Methods: The retrospective cohort study was conducted at a fertility center. The main inclusion criteria were age < 35 years, body mass index (BMI) < 28 kg/m, normal ovarian reserve (anti-Mullerian hormone ≥ 1.2 ng/ml, antral follicle count ≥ 5). Women undergoing the first oocyte retrieval cycle were included consecutively between 2018 until 2023. Patients who have ≤ 9 oocytes retrieved were defined as uPOR. The multivariable logistic model and subgroup analysis were conducted after adjusting confounders.

Results: A total of 6977 cycles were included. The adjusted odds ratio was 1.25 (95% confidence interval [CI], 1.12-1.39) for the increment of Ln HOMA-IR which was taken as a continuous variable. Meanwhile, as a sensitivity analysis, elevated tertile of HOMA-IR exhibited an increase in risk of uPOR for the third tertile (≥ 2.75) when compared with the first tertile (< 1.75) with OR of 1.33 (95%CI, 1.15-1.54). In the subgroup analysis, the positive association remained consistent.

Conclusion: Elevated HOMA-IR values is significantly associated with increased risk of uPOR in non-obese women classified as POSEIDON group 1. Our study provided evidence for the adverse influence of IR on the ovarian response during IVF and shed light on the importance of IR measurement at the time of pre-stimulation among non-obese women.