Department of Obstetrics and Gynaecology, National University of Malaysia, Jalan Yaacob Latiff, Bandar Tun Razak, Kuala Lumpur 56000, Malaysia.
Singapore Med J. 2011 Oct;52(10):734-7.
This study evaluated the effect of human semen cryopreservation using an ultra-low temperature technique with a mechanical freezer at -85°C as an alternative method to the conventional liquid nitrogen technique at -196°C.
This was a prospective experimental study conducted in the Medically Assisted Conception unit, Department of Obstetrics and Gynaecology, National University Hospital, Malaysia from January 1, 2006 to April 30, 2007. All normozoospermic semen samples were included in the study. The concentration, motility and percentage of intact DNA of each semen sample were assessed before and after freezing and thawing on Days 7 and 30 post freezing.
Sperm cryopreservation at -85°C was comparable to the conventional liquid nitrogen technique for a period of up to 30 days in a normozoospermic sample. There was no statistical difference in concentration (Day 7 p-value is 0.1, Day 30 p-value is 0.2), motility (Day 7 p-value is 0.9, Day 30 p-value is 0.5) and proportion of intact DNA (Day 7 p-value is 0.1, Day 30 p-value is 0.2) between the ultra-low temperature technique and conventional liquid nitrogen cryopreservation at Days 7 and 30 post thawing.
This study clearly demonstrates that short-term storage of sperm at -85°C could be a viable alternative to conventional liquid nitrogen cryopreservation at -196°C due to their comparable post-thaw results.
本研究评估了使用机械冷冻机在-85°C 的超低温技术对人类精液进行冷冻保存的效果，作为传统-196°C 液态氮技术的替代方法。
这是 2006 年 1 月 1 日至 2007 年 4 月 30 日在马来西亚国立大学医院妇产科辅助受孕科进行的前瞻性实验研究。所有正常精子样本均纳入研究。在冷冻和解冻后的第 7 天和第 30 天评估每个精液样本的浓度、活力和完整 DNA 的百分比。
在正常精子样本中，-85°C 的精子冷冻保存与传统液态氮技术在长达 30 天的时间内效果相当。在第 7 天（p 值为 0.1）和第 30 天（p 值为 0.2），超低温技术与传统液态氮冷冻保存的浓度、活力和完整 DNA 比例之间无统计学差异。
本研究清楚地表明，由于解冻后结果相当，因此将精子在-85°C 下短期储存可以作为传统-196°C 液态氮冷冻保存的可行替代方法。
