THE VALUE OF SEMEN CHARACTERISTICS AND TESTS OF SPERM FUNCTION IN SELECTING COUPLES FOR INTRAUTERINE INSEMINATION

In order to improve the selection of couples for intrauterine insemina tion (IUI) because of longstanding primary infertility of alleged male origin, we have performed a prospective study measuring conventional and advanced analysis of sperm characteristics, the hypoosmotic swelli ng test, the Shorr stain, the acidified aniline blue stain and alpha-g lucosidase activity in seminal plasma, of 89 couples with no demonstra ble abnormality of the female partner. Twenty-four couples attained sp ontaneous conception. 23 were successful within six cycles of IUI, and 42 remained without conception in spite of IUI during six unstimulate d cycles. The proportion and concentration of spermatozoa with progres sive motility was significantly lower (P < 0.01) in the successful IUI cases than in the couples attaining spontaneous conception, and the l ower quartile value was lower in the former than in the latter. There were less pregnancies among IUI treated couples when sperm concentrati on and motility were within the range of normal fertile men. or when t he concentration of white blood cells was elevated. More pregnancies o ccurred when markers of epididymal function, namely the result of the Shorr stain and alpha-glucosidase measurement, were normal. Total prog ressive motility and the result of the Shorr stain were the only indep endent variables selected by logistic regression to discriminate betwe en successful and failed IUI cases. It is concluded that only a limite d group of couples may benefit from IUI.