Association between semen parameters and chance of fatherhood - a long-term follow-up study

Background Evaluation of male fertility includes standard semen analysis; however, there is uncertainty about the value of sperm parameters in predicting fertility. Objective To evaluate the association between semen parameters and fatherhood during a long-time period. Materials and methods Semen parameters (total sperm count, concentration, motility, and morphology) and sperm DNA fragmentation Index (DFI) assessed on samples collected from 195 Norwegian men from the general population in 2001/2002 were matched with information about fatherhood until 2015, obtained from the Medical Birth Register. The parameters were dichotomized as normal vs. abnormal according to the WHO reference values from 1999 and 2010. Cut-offs at 20% and 30% were used for DFI. Results Among men who had no children before 2003, those with normal progressive sperm motility had more often become fathers (WHO 1999, cut-off >= 50%, adjusted OR 2.8, 95% CI 1.3-6.1 and WHO 2010, cut-off >= 32%; aOR 4.2, 95% CI 1.1-15). Based on the WHO 1999 reference value, men with normal sperm concentration (>= 20 x 10(6)/mL) had more often become fathers (aOR 3.1, 95% CI 1.1-8.6). Men with progressive sperm motility >= 50% and concentration >= 20 x 10(6)/mL did more often achieve fatherhood (aOR 8.4, 95% CI 2.1-34). For DFI, there was a borderline significance at cut-off 20% in the group of men who had ever been fathers (OR 2.7, 95% CI 1.0-7.0 p < 0.05). Discussion The results indicate that sperm progressive motility, sperm concentration, and DFI are associated with fatherhood during a longer time period, with sperm motility being most consistent. Although the sample size is relatively small and our results should be replicated in larger studies, they may be of clinical relevance. Conclusion Semen parameters may have a diagnostic value not only in a short time frame but also for predicting future fertility potential.