P-630 Assessing Bologna and POSEIDON criteria as predictors of PGT-A in Poor Ovarian Response: A comparative analysis
Authors: Marco Llopis A , Lledó B , Bidah N , Ortiz J  A , Morales R , Bernabeu A , Bernabeu R 
Published: July 2024

Abstract

Study question
Do Bologna or POSEIDON criteria more accurately predict PGT-A outcomes in poor ovarian response, considering aneuploidy rates and clinical outcomes?

Summary answer
Comparing Bologna and POSEIDON criteria highlights higher aneuploidy rates in Bologna patients, with no significant differences in mosaicism rate or clinical outcomes in either group.

What is known already
Ovarian reserve stands out as the primary factor influencing reproductive senescence. Approximately 9-24% of individuals undergoing ovarian stimulation are categorized as ‘low-responders’. Key indicators of Poor Ovarian Response (POR) include age, antral follicle count (AFC), Anti-Müllerian Hormone (AMH), and response to controlled ovarian stimulation. While some studies link ovarian reserve to embryo quality, others dispute any correlation with embryo abnormalities. The Bologna criteria classify patients meeting at least two of the following: advanced maternal age, low AFC, and AMH. The more precise POSEIDON criteria combine these factors, forming four distinct groups for classification.

Study design, size, duration
We conducted a retrospective case-control study, examining PGT-A results of 2740 embryos derived from 797 IVF cycles conducted in our clinic between 2021 and 2022.
Trophoectoderm biopsies, taken at D + 5/6, underwent Next-Generation Sequencing. Embryos were vitrified and transferred after analysis. Regarding the interpretation of the results, embryos with ≤25% cells aneuploids were considered euploid, between 25% and 50% were classified as mosaic and those with &gt;50% cells were considered aneuploid.

Participants/materials, setting, methods
All patients used their own oocytes. Bologna and POSEIDON criteria were used for the classification of POR and non-POR patients. Univariate analysis was performed using Pearson’s chi-square statistical test for categorical variables and binary logistic regression to compare the rates of aneuploidy and embryonic mosaicism, pregnancy rate miscarriage, ongoing pregnancy rate and implantation rate with the above variables taking into account possible confounding factors.

Main results and the role of chance
Patient ages ranged from 22 to 47 years, with a mean of 38.9 years. In Bologna groups, mean ages were 41.15 years for Bologna and 38.43 years for the control. For POSEIDON: 32.47 group I, 39.85y group II, 32.11y group III, 40.41y group IV and 38.24y control group of the classified by POSEIDON criteria. The mean AFC was 10.95 and the AMH value was 13.15pmol/L. Among 797 cycles, 59.16% (449/797) met POR criteria by POSEIDON, distributed across groups: 1.19% (9/797) in group I, 1.32% (10/797) in group II, 22.66% (172/797) in group III and 33.99% (258/797) in group IV. Using Bologna criteria, 17.74% (486/797) were classified as POR.
Our findings reveal that individuals identified with POR by Bologna criteria exhibit a significantly elevated incidence of embryo aneuploidy (78.8% POR patients vs. 59.9% control patients; p = 0.004). However, no such distinction was observed when employing the POSEIDON criteria for classification.
In terms of embryo mosaicism, no notable differences were detected between POR and non-POR patients under both Bologna and POSEIDON criteria. Furthermore, no significant variations in clinical data were observed between the two groups, even after correcting for maternal age.

Limitations, reasons for caution
The study is constrained by the inherent limitations of a retrospective design and a restricted sample size. Moreover, the complexity and heterogeneity involved in classifying patients with POR contribute to additional challenges in the interpretation of results.

Wider implications of the findings
The study indicates that diminished ovarian reserve does not significantly augment the probability of embryo aneuploidies. Particularly noteworthy is the observation that young women with low ovarian reserve do not exhibit an increased susceptibility to aneuploidies. This finding holds implications for understanding reproductive outcomes among ovarian reserve variations.

Trial registration number
No aplicable