Zollner U, Martin S, Liebermann J, Steck T
Department of Obstetrics and Gynecology, University of Würzburg, Germany.
Acta Obstet Gynecol Scand. 1999 Apr;78(4):326-31.
The aim of this study was to enhance the predictability of conventional semen parameters for in-vitro fertilization outcome. The utility of late sperm motility in presence of a cumulus-oocyte complex after different hours of incubation was investigated to predict the outcome of IVF in borderline and normal ejaculates (at least 5 x 10(6) motile sperm).
The study was done on 52 infertile couples undergoing conventional in-vitro fertilization and embryo transfer. Sperm were prepared by the Percoll cushion centrifugation with swim-down. Cocultures were established by inseminating the cumulus-oocyte complexes with 100000 motile spermatozoa and incubating them for 48 hours. Another 100000 spermatozoa were incubated in culture medium for 48 hours. Sperm motility (WHO a+b) was determined at 0, 4, 24 and 48 hours of incubation.
The fertilization rate was 65.5% (42.9-88.1). The conventional semen parameters did not correlate with the fertilization rate. Sperm motility measured after different hours of incubation was found to be significantly positively correlated with the fertilizing ability of sperm in vitro in Spearman's rank correlation test: motility after 0 h (p<0.02), after 4 h (p=0.0025). after 24 h (n.s.) and after 48 h (p=0.0071). Cut-off values for late sperm motility were determined and differences in fertilization rates were calculated for these cut-off values after different hours of incubation. A cut-off value of 20% progressive motile spermatozoa after 48 hours gave the best statistical power (fertilization rate 71.7 vs. 50.2%, p<0.001). Significant differences in the fertilization rates were also observed for a cut-off value of 35% after 24 hours of incubation (70.1 vs. 46.2%, p=0.001) and for a cut-off point of 60% after 4 hours (72.4 vs. 51.5%, p=0.001).
The predictive power of sperm motility after 48 h for fertilization outcome provides support in the decision-making process within the assisted reproduction setting. If less than 20% of sperm are motile after 48 h micromanipulatory techniques should be considered.
本研究的目的是提高常规精液参数对体外受精结局的预测能力。研究了在卵丘-卵母细胞复合体存在的情况下，不同孵育时间后的晚期精子活力对临界和正常射精（至少5×10⁶个活动精子）体外受精结局的预测作用。
对52对接受常规体外受精和胚胎移植的不育夫妇进行了研究。精子通过Percoll垫层离心和游动下沉法制备。通过用100000个活动精子对卵丘-卵母细胞复合体进行授精并孵育48小时来建立共培养体系。另外100000个精子在培养基中孵育48小时。在孵育0、4、24和48小时时测定精子活力（世界卫生组织a + b级）。
受精率为65.5%（42.9 - 88.1）。常规精液参数与受精率无关。在Spearman秩相关检验中，发现不同孵育时间后测定的精子活力与精子体外受精能力显著正相关：0小时后（p < 0.02）、4小时后（p = 0.0025）、24小时后（无显著性差异）和48小时后（p = 0.0071）。确定了晚期精子活力的临界值，并计算了不同孵育时间后这些临界值的受精率差异。48小时后20%的进行性活动精子的临界值具有最佳统计学效力（受精率71.7%对50.2%，p < 0.001）。在24小时孵育后35%的临界值（70.1%对46.2%，p = 0.001）和4小时后60%的临界点（72.4%对51.5%，p = 0.001）也观察到受精率的显著差异。
48小时后精子活力对受精结局的预测能力为辅助生殖环境中的决策过程提供了支持。如果48小时后活动精子少于20%，应考虑采用显微操作技术。
