New method of evaluating sperm morphology with predictive value for human in vitro fertilization

A prospective study was planned to evaluate sperm morphology as a parameter to predict the fertilization outcome in an in vitro fertilization program. Couples applying to in vitro fertilization were admitted into this project when the sperm concentration was >20 million per mL and motility >30 per cent. Based on new strict criteria for evaluating normal sperm morphology, patients were divided prospectively into 2 groups. In group 1(25 patients) normal sperm morphology was $ ̌14 per cent, and in group 11(71 patients) normal sperm morphology was >14 per cent, using a threshold established previously. Multiple regression analysis was used to evaluate different parameters: concentration, motility, and morphology against the dependent variables, fertilization, and cleavage. The only factor which was significantly correlated with fertilization and cleavage was normal sperm morphology (P < 0.0001). The fertilization rate (per oocyte) and the cleavage rate were 49.4 per cent and 47.6 per cent in group I and 88.3 per cent and 87 per cent in group II (P < 0.0001). The ongoing pregnancy rate per laparoscopy and per embryo transfer was 4 per cent and 5.5 per cent, respectively, in group I and 18.3 per cent and 18.5 per cent, respectively, in group II (no significant difference). This study demonstrates the value of analyzing sperm morphology using the criteria recommended in terms of predicting fertilization and perhaps pregnancy outcome. Patients can be better counseled and the probability of fertilization or no fertilization can be more accurately established. Furthermore a trend is shown in the pregnancy rate that may indicate the importance of the male genome in establishing a pregnancy. © 1987.