JBRA Assisted Reproduction 2025;29(Suppl.2 SBRA 2025):237
Poster Presentation
29^th Annual Congress of the SBRA. São Paulo/SP - Brazil, 2025
doi: 10.5935/1518-0557.20263844

P-225. The hidden cost of paternal age: How it affects IVF outcomes

Caroline Zulim Berton¹, Ivan Henrique Yoshida¹, Karla Pacheco Melo¹, Emerson Barchi Cordts¹, Caio Parente Barbosa¹

¹ Instituto Ideia Fértil de Saúde Reprodutiva - São Paulo – SP - Brasil

Objective: Evaluating the impact of paternal age on semen quality and embryonic development according to laboratory outcomes.
Methods: This retrospective study analyzed data from patients who underwent assisted reproductive technology (ART) at a private fertility clinic in Brazil. All embryos were cultured using a time-lapse incubator (EmbryoScope^®plus) and performed by preimplantation genetic testing for aneuploidy (PGT-A) between october, 2022 and april, 2025. A total of 312 embryos were included. Only cycles involving female patients aged ≤35 years were selected and male patients aged between 25 and 76 years whose sperm originated from ejaculate were stratified into four age groups: ≤35, 36–40, 41–49, >50 years. Patients with severe male factor infertility were excluded. For the seminal analysis, the parameters evaluated included: sperm concentration and motility. The following embryonic parameters were also assessed: Morphological parameters: evaluation of blastocyst – top quality or no top quality; Morphokinetics parameters: time-lapse imaging to assess dynamic cleavage events - time to 2 cells (T2), T3, T4, T5 and time to blastocyst formation (TB). Artificial intelligence (AI)-based developmental scores using algorithms provided by the iDAScore (version 2.0) software (Vitrolife^®); Genetic parameters: chromosomal or genetic integrity analisys by PGT-A screening for ploidy status (euploidy, aneuploidy and mosacism). Quantitative variables were expressed as mean±standard deviation with 95% confidence intervals and analyzed using the Kruskal-Wallis test for non-parametric variables and ANOVA for repeated measures in cleavage timing. For all analyses, the significance level was set at p<0.05. Statistical analyses were performed using Jamovi software, version 2.5.
Results: Male partners were stratified into four age groups: group 1: ≤35 years (n=120), group 2: 36–40 years (n=135), group 3: 41–49 years (n=32), and group 4: ≥50 years (n=25). For seminal parameters analisys the Kruskal–Wallis test revealed a significant effect of paternal age with higher levels on sperm concentration in group 1 vs group 2, 3 and 4 (p<0.001) and between group 2 and group 3 (p<0.001). Progressive motility (A+B) was significantly lower in groups 3 and 4 compared with group 1 (p<0.001) and with group 2 (p<0.001). Related to embryonic morphokinetics and morphology parameters, paternal age significantly influenced the iDAScore between groups 1 and 4 (p=0.016) and between groups 2 and 4 (p=0.006), as well as the proportion of top-quality blastocysts between groups 1 and 4 (p=0.013) and between groups 2 and 4 (p=0.002), with group 4 showing lower grades in both analyses. Repeated-measures ANOVA showed no significant interaction between paternal age and cleavage timing (p=0.927), indicating comparable developmental cell division across all groups. No significant differences in embryo ploidy status were found (p=0.869) when genetic embryonic parameters were analyzed.
Conclusion
Advanced paternal age can be associated with significant declines in sperm concentration and motility, as well as reduced embryonic morphokinetic and morphological parameters, particularly in men over 50 years of age. Nevertheless, these changes did not translate into differences in embryo chromosomal ploidy rates or abnormal cleavage pattens when oocytes from younger women are used.