Background: Gonadotoxic treatment for cancer or other diseases that damages male gamete production requires timely sperm cryostorage to insure against iatrogenic impairment of fertility.
Aim: To describe the sperm cryostorage experience in a single academic centre over 4 decades.
Methods: Men (n=2608, 2050 cancer, 238 non-cancer disease) seeking sperm cryostorage prior to gonadotoxic treatment from 1978 to 2016 and 255 healthy controls (sperm donors) were studied by semen analysis (WHO), testis volume (orchidometry) and hormone assays (immunoassay).
Results: Men referred for sperm cryostorage (mean age 30 years, range 12.8-67 years, 151 (6%) <18 yr) had testis (teratoma 243, seminoma 357), hematological (lymphoma 568, leukaemia 270), sarcoma (174) and other (438) cancers. Sperm was cryostored in 89% with 7% not storing due to azoospermia or poor sperm quality with few unable to collect (3.6%) or failing to attend (0.7%). Adolescents were equally likely to collect successfully. Most men deposited three ejaculates (52%) (producing a median of 23 straws per man) with 29% of men collecting fewer and 10% more ejaculates. Prior fertility was unknown in 73% and 47% were single. Median time in cryostorage was 5 years with a median of 7 years (80% confidence limits 1-15 years) to discard specimens (no longer required or death, 66%) or withdrawal for usage (7% including 0.14% post-mortem). Sperm cryostorage was feasible for all diseases although sperm output was lower than healthy controls for all diseases except leukemia, non-Hodgkins lymphoma and sarcomas with reduced total testis volume and impaired spermatogenesis (high FSH), but not recent systemic symptoms (fever, weight loss), contributing significantly to these differences.
Conclusion: Sperm cryostorage prior to gonadotoxic treatment is feasible for virtually all men and should be an integral part of comprehensive cancer treatment programmes.