Dados do Trabalho

Title

Advanced Paternal Age and laboratory outcomes in IVF treatment

Objective

Advanced paternal age (APA) has been recognized as a potential risk factor in In vitro fertilization (IVF) outcomes in the last years with increasing evidence showing that as much as advance maternal age (AMA), APA can also have deleterious effect on gamete genetics, development and conception rates. However, there still no consensus for the definition of APA and few studies had explore a clear effect of paternal age stratification in IVF results, especially embryo development outcomes. Our objective was to access the possible correlations between paternal age stratify and embryo development outcome.

Methods

We collect data from January 2020 to December 2022 from all IVF cycles perform in our center, we excluded all procedures with mild/severe male factor or those conducted with donor/frozen samples. The medical records of the patients include in the study were retrospectively reviewed to identify embryo development parameters. Patients’ characteristics are presented as mean ± standard deviation or percentage. Male patients were categorized by age in the time of procedure and stratified in 3 groups as ≤34, 35-39, ≥40 years old. We included as embryo development outcomes: fertilization rate (number of fertilized embryos/number of inject oocytes), blastulation rate ( total number of blastocysts/ number of fertilized embryos) and good quality embryo rate (number of good quality blastocyst/ number of fertilized embryos) – being considered good quality embryos those with morphological classification A or B in inner cell mass and trophectoderm as Garner parameters. Continuous variables were compared between age groups using analysis of variance if normally distributed or Kruskal-Wallis if not normally distributed. Chi-square or Fisher’s exact test were used whenever appropriate for comparing categorical data. Male age group was correlate trough Pearson correlation test with the embryo development outcomes to access possible correlation between male age category and laboratory outcomes in IVF cycles. Statistical analyses was conducted with the software SPSS 20 (IBM- Chicago,IL,UDSA).

Results

A total sample of 240 IVF cycles were included in our study. Medium male age of ≤34 group was 34 ±0 years old(N=7), 35-40 group was 37,23 ± 1,82 years old (N=113), ≥40 group 44,58 ± 5,22 years old (N=110). Respectively female age was 35,33 ± 2,58, 35,99 ± 2,99, 38,8 ± 2,65. No significant difference was found between age groups in any of the continuous or categorical variables analyzed. Medium fertilization rate in each group was, respectively, 81,5%, 70,1% and 72,1%, medium blastulation rate was, respectively, 49,2%, 50,7% and 50,7%, and lastly medium good quality embryos rate was, respectively, 23,3%, 36,2% and 31,6%. A negative correlation was observed between male age and good quality embryos (-0,138, p= 0,034). However no significant result was observed with male age stratifications.

Conclusion

Previous data already extensively assessed the potential influence of paternal age in IVF outcomes, still few studies have found clear correlation between advanced paternal age and rates of fertilization, implantation, pregnancy, miscarriage, and live birth. In our results paternal age was found to correlated with embryo quality at blastocyst stage, what could reflect male genomic activation within the embryo. Our goal to observed if male age stratification could show impact on laboratory results show no significance.

Keywords

male infertility; paternal age; in vitro fertilization; embryo development