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Mouse Sperm Cryopreservation and Recovery using the I·Cryo Kit
Published on: December 12, 2011
Sperm Cryopreservation Activity and Quality Assurance of Cryogenic Storage at a University Hospital in Oujda, Morocco
Boutayna Elrhaffouli1, Dounia El Moujtahide1, Hicham Ezzaidi1
1Biochemistry, Mohammed VI University Hospital, Oujda, MAR.
Abstract:
Background Sperm cryopreservation is the standard method for preserving male fertility in patients at risk of impaired reproductive function. As the demand for fertility preservation increases, maintaining optimal cryogenic storage conditions through robust quality assurance programs has become essential to ensure the long-term safety of cryopreserved specimens. Objective The primary objective was to evaluate the quality assurance program for cryogenic storage at the Assisted Reproductive Technology and Gamete Cryopreservation Unit of Mohammed VI University Hospital in Oujda, Morocco. As a complementary objective, we described the unit's sperm cryopreservation activity and clinical indications to contextualize the biological specimens whose long-term safety depends on this storage system. Methods A retrospective descriptive and analytical study was conducted between March 2022 and November 2025. Fifty-nine sperm cryopreservation procedures were analyzed. Semen parameters were analyzed according to the World Health Organization (WHO) recommendations. Clinical indications were classified as oncological or non-oncological. Comparisons were performed using the Mann-Whitney U and Kruskal-Wallis tests, while correlations were assessed using Spearman's rank correlation coefficient. Additionally, 381 liquid nitrogen monitoring records were analyzed to assess storage stability, evaporation rates, refill frequency, seasonal variations, and temporal trends in cryogenic storage performance. Results The mean patient age was 31.1±9.2 years. Oncological indications predominated, with testicular tumors representing the most frequent indication, followed by hematological malignancies. Patients with oncological indications were significantly younger than those with non-oncological conditions (p<0.001) and differed significantly in sperm concentration (p=0.028) and the number of cryopreserved straws (p=0.015). A positive correlation was observed between sperm concentration and motility (ρ=0.373; p=0.004). Monitoring of cryogenic storage demonstrated excellent storage stability, with no breach of the cryogenic storage chain or loss of biological specimens during the study period. Seasonal analysis revealed significantly higher liquid nitrogen evaporation rates during the warm season for one storage tank (p=0.040), while annual evaporation rates varied significantly over the four-year period (p<0.001). Conclusion At our institution, sperm cryopreservation was used for both oncological and non-oncological indications. Over the study period, structured monitoring and preventive refilling maintained safe storage conditions without a recorded breach of the cryogenic chain or specimen loss, despite seasonal and temporal variation in liquid nitrogen consumption. These institution-specific findings support continued rigorous monitoring but require confirmation in larger, multicenter studies.
