Comparative evaluation of aromatase inhibitors and their combination with recombinant follicle-stimulating hormone in assisted reproductive technology programs for cancer patients

Background. Fertility preservation is a critical component of comprehensive cancer treatment. One promising method for obtaining genetic material is superovulation stimulation using letrozole.

Aim. Comparative assessment of the efficacy and safety of protocols using letrozole alone and in combination with recombinant follicle-stimulating hormone.

Materials and methods. The study included 130 patients with reproductive system malignancies. Participants were divided into two groups based on the superovulation induction protocol used, with further stratification by anti-Müllerian hormone (AMH) level (<1.2 ng / mL and ≥1.2 ng / mL). All patients underwent superovulation stimulation, oocyte retrieval with quantitative assessment, and dynamic monitoring of estradiol levels before / after stimulation.

Results. In the subgroup of patients with AMH levels ≥1.2 ng / mL (n = 90), the combination of letrozole with recombinant follicle-stimulating hormone demonstrated superior outcomes, more oocytes compared to letrozole monotherapy (8.6 ± 3.1 vs 5.3 ± 5.1; p = 0,02). While the proportion of patients achieving estradiol levels <50 pg / mL showed no significant difference between groups (22 % vs 18 %; p = 0.62).

For patients with AMH levels <1.2 ng / mL (n = 40), both protocols showed comparable efficacy in terms of oocyte retrieval (2.8 ± 2.5 vs 2.1 ± 2.3; p = 0.42). However, the combination therapy provided significantly better estradiol suppression (77 % level reduction vs 65 %; p = 0.03), suggesting improved hormonal control in this patient population.

Conclusion. For patients with AMH ≥1.2 ng / mL, letrozole + recombinant follicle-stimulating hormone significantly increases oocyte yield without substantially elevating estradiol risk, supporting its use in fertility preservation programs. Patients with diminished ovarian reserve require further clinical investigation

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