Reproductive potential of fresh and cryopreserved epididymal and testicular spermatozoa in consecutive intracytoplasmic sperm injection cycles in the same patients.
OBJECTIVE
To determine if the cryopreservation of epididymal and testicular spermatozoa alters their reproductive potential by examination of patients who underwent consecutive cycles of ICSI using fresh and then cryopreserved spermatozoa.


METHODS
Retrospective review.


METHODS
Tertiary care university hospital.


METHODS
One hundred sixty-two consecutive cycles of ICSI were analyzed. Thirteen patients were identified as having undergone treatment with freshly retrieved epididymal spermatozoa; these patients subsequently underwent treatment with spermatozoa cryopreserved from that cycle. Eighteen patients underwent ICSI with freshly retrieved testicular spermatozoa; these patients subsequently underwent treatment with spermatozoa cryopreserved from that cycle.


METHODS
None.


METHODS
Fertilization rates and pregnancy rates.


RESULTS
The fertilizing capacity of epididymal spermatozoa remained unchanged after cryopreservation and subsequent thawing, with fertilization rates of 58% and 57% for fresh and cryopreserved spermatozoa, respectively. Testicular spermatozoa, however, showed a significant decrease in fertilizing capacity after cryopreservation when compared with freshly retrieved spermatozoa (52% and 71%, respectively). Pregnancy rates appeared unaffected by the cryopreservation of epididymal spermatozoa (fresh, 3/13; frozen, 2/13) or testicular spermatozoa (fresh, 2/18; frozen, 5/18).


CONCLUSIONS
This study offers further evidence that motile epididymal spermatozoa retain their fertilizing capacity after cryopreservation. The data presented on testicular spermatozoa suggest that although cryopreservation may reduce the fertilizing capacity of testicular spermatozoa, there is no decrease in pregnancy rates.
Wood
Simon
S
Reproductive Medicine Unit, Liverpool Women's Hospital, England, UK. simon_j.wood@virgin.net
Thomas
Kevin
K
Schnauffer
Karen
K
Troup
Stephen
S
Kingsland
Charles
C
Lewis-Jones
Iwan
I
D000328:Adult; D015925:Cryopreservation; D004822:Epididymis; D005260:Female; D005306:Fertilization; D006801:Humans; D008297:Male; D008677:Metaphase; D008875:Middle Aged; D009865:Oocytes / Q000502:physiology; D011247:Pregnancy; D018873:Pregnancy Rate; D012189:Retrospective Studies; D020554:Sperm Injections, Intracytoplasmic; D013094:Spermatozoa / Q000502:physiology*; D013737:Testis