P-062 The influence of the ejaculatory abstinence period on semen parameters from the first diagnostic sample – results from analysis of 14000 samples

Abstract

Abstract Study question Is ejaculatory abstinence period (EAP) associated with semen parameters in males undergoing preliminary fertility investigation? Summary answer Short EAP is associated with increased progressive motility (%), vitality but with reduced volume, concentration, total sperm count. No association was indentified with morphology, DNA fragmentation. What is known already It is known that semen parameters may present important intra-individual variations. At present, the last edition of the WHO Manual recommends ejaculatory abstinence from two to seven days for semen analysis. Nonetheless, this period is not supported by some relevant bodies in the reproductive field guidelines that limit abstinence period to three or four days. Recently published reviews on this matter support that the relationship between the abstinence time and sperm quality is not straightforward. Therefore the aim of this study is to analyze correlation between the ejaculatory abstinence time and sperm parameters in patients having initial work-up in our clinic. Study design, size, duration We conducted a retrospective cross-sectional study on the diagnostic semen samples from individuals having their initial fertility investigation in the Fertility Department of a University Affiliated Hospital between the beginning of 1997 and the end of 2022. Basic semen parameters and sperm deoxyribonucleic acid (DNA) fragmentation were registered in 14067 and 784 samples respectively. Sperm morphology was analysed in 4812 samples. Participants/materials, setting, methods We included exclusively results from the first diagnostic semen sample from males of any age undergoing preliminary infertility work-up. All samples were produced on-site and analysed “ad hoc” for basic semen parameters (according to 6th Edition of WHO Manual) or/and sperm DNA fragmentation (Sperm Chromatin Dispersion test). Samples were divided according to EAP: ≤2(A-group); 2-7(B-group); >7 days (C-group) and compared with ANOVA. Additionally, Spearman Correlation was used to confirm correlation between EAP and sperm parameters. Main results and the role of chance Semen analysis was performed either completely manually (23.4%) or with the use of Computer Assisted Semen Analysis (CASA) system (76.6%) with the exception of morphology which was always assessed manually. Overall, 661 samples were produced after ≤2 days of abstinence, 12734 after 2 to maximum 7 days and 690 after >7 days of which ones 330(50%), 6798(53%) and 336(49%) were normozoospermic, respectively. Mean male age was 39 years (SD 6.5) and EAP 4.5 days (SD 1.9). We found the following parameters positively correlated with EAP in both normozoospermic and abnormal samples: volume (A-2.6ml; B-3.6ml; C-4ml, p < 0.05), concentration (A-72M/ml; B-93M/ml; C-127M/ml, p < 0.05), total sperm count (A-161M; B-285M; C-472M, p < 0.05), total motile count (A-111M; B-186M; C-270M, p < 0.05), straightness coefficient (STR) (A-73.1; B-75.7; C-77.8%, p < 0.05) and Zinc concentration (A-14277; B-17375; C-22538µg/dl, p < 0.05). The following parameters were negatively correlated with EAP in both normozoospermic and abnormal samples: progressive motility (A-46; B-43.6; C-36.6%, p < 0.05), vitality (A-60.5; B-60.3; C-53.7%, p < 0.05). We did not find any correlation with leucocytes, fructose, morphology or DNA fragmentation in unselected patients. However, in the group of abnormal samples there was a negative correlation between EAP and morphology (A-3.7; B-3.1; C-2.8%, p < 0.05) and DNA fragmentation, in generalized additive model (Spearman-Correlation, R2 0.01, p < 0.05). Limitations, reasons for caution This is a cross-sectional study which demonstrates only association and does not allow establishment of a cause-effect relationship between EAP and sperm parameters. Additionally, despite significant correlation between EAP and some sperm parameters, its clinical usefulness remains unclear. Wider implications of the findings To our knowledge this is first study correlating EAP with semen parameters only from diagnostic semen samples produced on-site, which confirms that the abstinence time should be seriously considered when analysing ejaculates, especially when borderline results are obtained. Additionally, different clinical strategies may be considered for normo and non-normozoospermic patients. Trial registration number not applicable