Males with subnormal hypo-osmotic swelling test scores have lower pregnancy rates than those with normal scores when ovulation induction and timed intercourse is used as a treatment for mild problems with sperm count, motility, or morphology.

This study was designed to evaluate the effectiveness and clinical usefulness of the hypo-osmotic swelling (HOS) test in predicting successful conception in couples in which men with mild male-factor infertility criteria were undergoing a timed vaginal intercourse protocol. One hundred couples, in which mild male infertility was the only abnormality, were included in the study. Semen was analyzed according to standard World Health Organization (WHO) criteria and subjected to the HOS test. Patients were divided into 2 groups: group 1 (n = 39) with normal HOS test and group 2 (n = 61) with abnormal HOS test. All women underwent three consecutive cycles of follicular growth ultrasound monitoring and timed intercourse. Ten couples were exclude from the study. Ten clinical pregnancies were achieved in group 1 with a pregnancy rate per patient and per cycle of 28.5% and 9.5%, respectively. In group 2, 6 pregnancies were achieved, with a pregnancy rate per patient and per cycle of 10.9% and 3.6%, respectively. Both pregnancy rates per patients and per cycle was significantly higher (P < .05) in group 1 than in group 2. The HOS test may be considered an easy and reliable test in identifying among subfertile men those who have a greater possibility of causing pregnancy.