Introduction: The aim of this study was to evaluate the effect of a consecutive second ejaculate, i.e, to determine if it contains an equal, or even higher, number of motile sperm, and whether it can improve the fertilization rate in IVF-ET treatment.

Material and methods: From July 1996 through April 2007, 32 cycles in 22 couples, who had previously exhibited oligoasthenozoospermia, were recruited in this study. The first ejaculate was obtained after 3-5 days following sexual ejaculate abstinence. The second ejaculate was obtained 30-60 min after the first one. Several parameters concerning sperm quality and fertilization rate in IVF were compared between the first and second ejaculation.

Results: The mean duration between the first and second ejaculation was 34.2 min (mean ± SEM). The second ejaculate showed a significant reduction in the volume of ejaculate. The sperm motility (35.2±13.3) and motile sperm concentration (5.4±7.3) of the second ejaculate were significantly higher than those of the first (24.3±13.2 and 2.2±1.8, respectively; P<0.05). The fertilization rate of sperm from the second ejaculate (53.3%) was significantly higher than that from the first one (28.9%, P<0.05), but cleavage rates and embryo scores were similar.

Conclusions: Therefore, this sequential ejaculation might be useful for treatment of male infertility at these hospital and clinics.