P–090 Cumulative live birth rates (CLBR) per embryo transfer, embryo transferred and inseminated oocyte are not affected by paternal age in infertile male donor egg cycles
Authors: Mossetti L , Navarro-Gomezlechon A , Rivera-Egea R , Hervas I , Gi. Julia M , Garrido N 
Published: August 2021

Abstract

Study question
Is reproductive success measured as CLBR per inseminated oocyte, per embryo transfer and per embryo transferred affected by paternal age in donor egg IVF-ICSI cycles?

Summary answer
Paternal age does not significantly affect reproductive outcomes measured by CLBR per inseminated oocyte, embryo transfer and embryo transferred in donor egg IVF-ICSI cyles.

What is known already
In recent years, the delay in the start of formation of a family has led to an increase of the average male age at which the first child is conceived. Therefore, there is a growing interest on the study of the impact of male age on the reproductive outcomes in assisted reproduction cycles (ART). Several studies have evaluated the effect of paternal age on reproductive outcomes using donor egg cycles to control for female factors. However, the results obtained on this topic are still controversial leading to a need of more research about it, which this study tries to address.

Study design, size, duration
This retrospective observational multicentric cohort study has included donor IVF-ICSI treatments (n = 1539) performed to couples with etiology of male infertility (non-normozoospermic) in Spain IVIRMA clinics between January 2008 and March 2020 using patients’ own sperm sample. Paternal age ranged from 28 to 74 years. The study population was categorized in 5 groups following the criterion of homogenizing the number of observations between groups 28–38 (A), 38–41 (B), 41–44 (C), 44–48 (D) y 48–74 (E) years.

Participants/materials, setting, methods
Considering that male age could be a factor affecting reproductive outcomes, we evaluated men with different age that performed a donor IVF-ICSI treatment with their own semen, etiology of male infertility and known age. Data was exported in order to obtain the clinical database and Kaplan-Meier was used for data analysis. P &lt; 0.05 was considered statistically significant. We measured reproductive success by CLBR per embryo transfer, per embryo transferred and per inseminated oocytes until live birth.

Main results and the role of chance
This study considered approximately 836 patients and 1411 embryo transfers. The CLBR per inseminated oocyte showed no significant difference between the study groups: A (3.09%, 42.61%, 71.96%), B (4.53%, 39.76%, 84.19%), C (5.89%, 47.04%, 78.61%), D (2.99%, 46.7%, 73.15%) and E (3.89%, 38.39%, 78.85%) for 7, 12 and 17 inseminated oocytes, respectively. In terms of CLBR per embryo transfer, the results obtained for each of the age groups were: A (51.55%, 70.69%, 92.18%), B (50.40%, 78.13%, 100.00%), C (53.68%, 71.69%, 100.00%), D (51.71%, 79.72%, 100.00%) and E (46.69%, 60.02%, 70.01%) for 3, 5 and 7 embryo transfers, respectively. No statistically significant differences were found among the studied age groups. CLBR per embryo transferred also did not show statistically significant differences between the age groups: A (8.43%, 53.34%, 72.13%), B (8.55%, 44,67%, 71.65%), C (10.40%, 53.94%, 72.49%), D (7.25%, 43.61%, 75.12%) and E (8.21%, 45.99%, 64.55%) for 1, 4 and 7 embryos transferred, respectively. Therefore, no significant differences were found in the number of inseminated oocytes, embryo transfers and embryos transferred needed to achieve a live birth between the age groups (p &gt; 0.05), suggesting that maybe paternal age has no relevant clinical effect on donor egg cycles with our categorization.

Limitations, reasons for caution
The retrospective nature of this study leads to biases derived from the clinical practice and to the presence of missing data (limiting sample size). Moreover, this study included donor egg cycles for controlling female factors, so this limits the generalization of our results to a population of young women.
Wider implications of the findings: Our study showed that the reproductive success measured as CLBR per embryo transfer, embryo transferred and inseminated oocytes was not statistically significant different among the studied age groups in donor egg cycles. Therefore, considering our study setting, paternal age does not affect reproductive success, however further studies should be done.

Trial registration number
NA