Chuan Huang1, Run-Xin Gan1, Huan Zhang1, Wen-Jun Zhou2, Zeng-Hui Huang3, Su-Hua Jiang2, Xi-Ren Ji2, Fei Gong3, Li-Qing Fan3, Wen-Bing Zhu4. 1. Reproductive and Genetic Hospital of CITIC-Xiangya, Changsha, People's Republic of China. 2. Institute of Reproductive and Stem Cell Engineering, Basic Medicine College, Central South University, Changsha, People's Republic of China. 3. Reproductive and Genetic Hospital of CITIC-Xiangya, Changsha, People's Republic of China; Institute of Reproductive and Stem Cell Engineering, Basic Medicine College, Central South University, Changsha, People's Republic of China. 4. Reproductive and Genetic Hospital of CITIC-Xiangya, Changsha, People's Republic of China; Institute of Reproductive and Stem Cell Engineering, Basic Medicine College, Central South University, Changsha, People's Republic of China. Electronic address: zhuwenbing0971@sina.com.
Abstract
OBJECTIVE: To evaluate a novel micro-straw as an efficient, simple method for freezing a small number of human spermatozoa for intracytoplasmic sperm injection (ICSI). DESIGN: Prospective cohort study. SETTING: Sperm bank. PATIENT(S): Men with severe oligozoospermia or azoospermia undergoing a total of 143 ICSI cycles at the CITIC-Xiangya Hospital of Reproduction and Genetics from June 1, 2015, to June 31, 2019, and 20 donors at the Hunan Province Human Sperm Bank from 2001 to 2016. INTERVENTION(S): Analysis of sperm samples and clinical outcomes after sperm use. MAIN OUTCOME MEASURE(S): Clinical information, including number of motile sperm before and after freezing, freeze-thaw survival rates, two-pronuclear fertilization rates, clinical pregnancy, and early pregnancy loss rates after sperm use. RESULT(S): In the feasibility experiment using the micro-straw, we found a freeze-thaw survival rate of 73% ± 8.3% and no difference in normal sperm morphology, normal acrosome integrity, or DNA fragmentation index between the micro-straw and 1.8-mL cryotubes. The prospective cohort included 1,325 cases, and we collected sperm from testicular, epididymis, and ejaculation sources. We observed motile sperm in 1,294 (97.6%) of 1,325 frozen-thawed samples. Postthaw sperm were available for ICSI in 140 (97.9%) of 143 of cycles. The fertilization, cleavage, and high-quality embryo rates were 1,007 (81.7%) of 1,233; 995 (98.8%) of 1,007; and 537 (53.9%) of 995, respectively. Sixty-nine (49%) clinical pregnancies were achieved, and the miscarriage rate was 6 (8.6%) of 69. CONCLUSION(S): The micro-straw is suitable and clinically useful for the cryopreservation of small numbers of spermatozoa.
OBJECTIVE: To evaluate a novel micro-straw as an efficient, simple method for freezing a small number of human spermatozoa for intracytoplasmic sperm injection (ICSI). DESIGN: Prospective cohort study. SETTING: Sperm bank. PATIENT(S): Men with severe oligozoospermia or azoospermia undergoing a total of 143 ICSI cycles at the CITIC-Xiangya Hospital of Reproduction and Genetics from June 1, 2015, to June 31, 2019, and 20 donors at the Hunan Province Human Sperm Bank from 2001 to 2016. INTERVENTION(S): Analysis of sperm samples and clinical outcomes after sperm use. MAIN OUTCOME MEASURE(S): Clinical information, including number of motile sperm before and after freezing, freeze-thaw survival rates, two-pronuclear fertilization rates, clinical pregnancy, and early pregnancy loss rates after sperm use. RESULT(S): In the feasibility experiment using the micro-straw, we found a freeze-thaw survival rate of 73% ± 8.3% and no difference in normal sperm morphology, normal acrosome integrity, or DNA fragmentation index between the micro-straw and 1.8-mL cryotubes. The prospective cohort included 1,325 cases, and we collected sperm from testicular, epididymis, and ejaculation sources. We observed motile sperm in 1,294 (97.6%) of 1,325 frozen-thawed samples. Postthaw sperm were available for ICSI in 140 (97.9%) of 143 of cycles. The fertilization, cleavage, and high-quality embryo rates were 1,007 (81.7%) of 1,233; 995 (98.8%) of 1,007; and 537 (53.9%) of 995, respectively. Sixty-nine (49%) clinical pregnancies were achieved, and the miscarriage rate was 6 (8.6%) of 69. CONCLUSION(S): The micro-straw is suitable and clinically useful for the cryopreservation of small numbers of spermatozoa.