Objective To explore the correlations between various insulin resistance (IR) assessment indicators and embryo quality and pregnancy outcomes during in vitro fertilization and embryo transfer (IVF-ET) in patients with polycystic ovary syndrome (PCOS).

Methods A retrospective cohort design was used, including PCOS patients who received in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment for the first time from January 2019 to July 2022. Assessment indicators of insulin resistance (IR) based on fasting status (HOMA-IR, QUICKI, Li Guangwei Index, Bennett ISI), collectively referred to as static IR indicators, and assessment indicators based on the oral glucose tolerance test (OGTT) (area under the curve ratio, Matsuda Index, Gutt Index), collectively referred to as dynamic IR indicators, were selected. Patients were divided into the IR group (high level) and the non-IR group (low level) according to the median. Differences in the levels of various IR assessment indicators, embryo quality, and pregnancy outcomes were compared. The primary outcome indicators were the D3 high-quality embryo rate (high embryo rate), fresh cycle clinical pregnancy rate, cumulative pregnancy rate, and cumulative live birth rate; other outcomes were considered secondary indicators. A multivariate binary logistic regression model was used to adjust for confounding factors, and multiple comparison correction was applied to control false positives when analyzing the correlation between different levels of IR assessment indicators and embryo quality and pregnancy outcomes.

Results A total of 571 PCOS patients were included, all of whom had fasting blood glucose and insulin data. Among these, 499 cases had complete OGTT data. Main outcome indicators: There was no statistical correlation between the levels of static IR indicators and the main outcome indicators. The levels of dynamic IR indicators (Gutt index) were associated with the pregnancy rate of good embryos, with an adjusted odds ratio (OR) of 0.88 (95% CI: 0.79-0.99, P = 0.035). The levels of the Matsuda index were associated with the cumulative pregnancy rate, with an adjusted OR of 0.61 (95% CI: 0.39-0.97, P = 0.036). Secondary outcome indicators: No statistically significant correlations were observed between the static IR indicators and dynamic IR indicators after multiple comparison correction.

Conclusion The Matsuda index and Gutt index based on OGTT are more sensitive than static fasting indicators in reflecting differences in reproductive outcomes among PCOS patients, and thus have significant clinical value.