Purpose: The length of sexual abstinence seems to influence sperm quality. However, few data on the relevance of abstinence time in pathological sperm samples are available. With our study, we look for associations of abstinence length and semen quality.
Methods: We studied semen samples from 4423 men undergoing fertility evaluation. Sperm concentration, percentage of progressively motile spermatozoa, total motile sperm count, percentage of spermatozoa with normal morphology, were compared after each day and 0-2, 3-7 and >7 days of abstinence.
Results: We found that a longer abstinence time was related to higher sperm concentration in normal semen samples (P<0.001) and in semen samples with any sperm pathology (P<0.001, P=0.004) with the exception of oligozoospermia (P=0.125). Longer abstinence time was also associated with significantly reduced progressive motility in normal samples (P<0.001) and in cases of teratozoospermia (P<0.001). In normal samples a higher percentage of sperm were morphologically normal after a shorter abstinence period (P=0.03); in oligoasthenoteratozoospermia (OAT) samples, this was the case after a longer abstinence period (P=0.013).
Conclusion: A longer abstinence time is associated with higher sperm concentration, whereas sperm motility is optimal after shorter abstinence times; results on morphology are controversial. The recommendation on abstinence time needs to be adjusted in relation to the parameter that needs to be improved.