P-043 Increased paternal age adversely affects live birth rates in oocyte recipient cycles
Authors: Atik Y , Halimeh R , Zomer M , Odia R , Kastora S , Exeter H , Vasilic M , Cawood S , Saab W , Serhal P , Seshadri S , Mavrelos D , Yasmin E 
Published: June 2023

Abstract

Study question
To investigate the influence of paternal age on the live birth rates in oocyte recipient cycles

Summary answer
Increased paternal age appears to have a negative impact on oocyte recipient cycles when adjusted for sperm quality.

What is known already
While the effect of maternal age on ART outcomes is well established, the effect of paternal age is unclear. Even systematic reviews assessing the impact of paternal age in oocyte recipient cycles have yielded conflicting results. While Morris et al., 2020 could not demonstrate changes in miscarriage rates or live birth rates with increased paternal age, Murugesu et al., 2022 showed an adverse effect of increased paternal age on miscarriages but did not comment on live birth rates. The challenges of systematic reviews are the heterogeneity of the studies and the possible effect of laboratory and clinical practices.

Study design, size, duration
This retrospective cohort study was conducted at a single centre. A total of 449 IVF/ICSI oocyte recipient cycles performed between January 2015 and June 2022 were examined. Total of 328 cycles resulting in either fresh or frozen-thawed embryo transfers and meeting the inclusion criteria was analysed. The inclusion criteria were donor age ≤35 years, endometrial thickness ≥ 6 mm and a normal endometrial cavity on aqua scan. We excluded cycles with donor sperm or PGT-A.

Participants/materials, setting, methods
The couples who used donor oocytes because of diminished ovarian reserve, premature ovarian insufficiency, recurrent implantation failure with autologous oocytes or hereditary disease participated. Paternal and recipient ages were grouped according to previous literature to allow for comparability. The primary outcome was the live birth rate and secondary outcomes were clinical pregnancy and miscarriage rates. Simple and multivariate logistic regression analyses were performed.

Main results and the role of chance
The median recipient and paternal ages were 42 years (interquartile range [IQR] 19–50) and 42 years (IQR 19–76), respectively. The mean age of the donors was 26 years (IQR 18-35).
55.5% [N = 182] of the cycles corresponded to fresh embryo transfers and 44.5% [N = 146] to frozen embryo transfers. Indications for using donor oocytes were diminished ovarian reserve 54.39%, premature ovarian insufficiency 5.7%, recurrent implantation failure with autologous oocytes 37.05% and hereditary disease 2.85%.
The overall live birth rate was 155/328 (45.7%). Live birth outcome appeared to be significantly reduced in paternal age over 46 years after adjusting for semen parameters according to WHO 2010 criteria and for recipient age, with an OR 1.5 (95%,0.85 to 1.98, p &lt; 0.002). Clinical pregnancy outcome was significantly reduced in paternal age over 51 years with OR 0.62 (95%, 0.31 to 1.89, p &lt; 0.0001). The overall miscarriage rate was 15/328 (4.57%) and it was not possible to perform subgroup analysis by paternal age group due to the small numbers.
When both maternal and paternal age were retained in the multivariate model, the probability of live birth decreased with paternal age over 51 years and maternal age ≥40 years with OR 0.88 [0.40 to 1.38 [N = 37]).

Limitations, reasons for caution
This study has some limitations. This is a retrospective study and its relatively small subgroup sizes affected the statistical analysis of miscarriage results. In addition, we did not include any effect of sperm DNA fragmentation in the analysis.

Wider implications of the findings
The overall live birth outcome was positive. Whilst the study can be used to counsel couples with increased paternal age, it should not be used to preclude patients from treatment.

Trial registration number
IRB-003C02-09-21