Insulin Resistance Adversely Affect IVF Outcomes in Lean Women Without PCOS.

Objective: To investigate the effects of insulin resistance (IR) on IVF outcomes and a potential underlying mechanism in lean women without PCOS.

Design: A prospective cohort study at the University Clinic.

Setting: IVF center at the University setting.

Patients: A total of 155 lean women (body mass index <25) without PCOS undergoing IVF cycle.

Intervention: Patients were allocated to IR and non-IR groups based on HOMA-M.

Main Outcome Measures: IVF outcomes, including egg quality, the percentage of mature oocytes, fertilization rate, blastocyst formation rate, advanced embryo rate, and cumulative live birth rate were investigated. Auto-immune parameters, peripheral blood immunophenotypes, thyroid hormone, homocysteine, and 25-OH-vitamin D (25-OH-VD) levels were analyzed.

Results: The percentage of mature oocytes and blastocyst formation rate were significantly lower in the IR group as compared with those of the non-IR group (p<0.05, respectively). The proportion of peripheral blood CD19 B cells was significantly higher in the IR group than those of the non-IR group (p<0.05). Homocysteine, 25-OH-VD and auto-immune parameters were the same between the two groups.

Conclusion: In lean infertile women without PCOS, IR is associated with the decreased percentage of mature eggs and poor embryo quality in which B cell immunity may play a role.