How often should infertile men have intercourse to achieve conception?

Objective: To clarify how often infertile men should have intercourse to achieve conception, the effect of sequential ejaculation on total motile sperm counts was investigated. Design: Case-control study. Setting: Infertility and IVF unit, tertiary care center. Participants: Five hundred seventy-six men who produced two closely spaced sequential ejaculates. Main Outcome Measure: The total motile sperm counts of the second ejaculates were compared with the total motile sperm counts of the first ejaculates. Results: In normospermic men (n = 359), the total motile sperm counts decreased significantly from 93 (18 to 601) (median [minimum to maximum] x 10⁶) in the first ejaculate to 42 (1.2 to 387) in the second ejaculate, produced 24 hours later. In contrast to the normospermic men, in the asthenospermic group (24 hours difference, n = 81) and in both oligospermic groups, (1 to 4 hours difference, n = 27; and 24 hours difference, n = 45), there were no significant changes in the total motile sperm counts (24 [5.9 to 229] versus 30 [0.8 to 150], 6 [0.8 to 18] versus 3.6 [0.1 to 63] and 13 [2.5 to 32] versus 10 [0.1 to 66], respectively). Moreover, in both oligoasthenospermic groups (1 to 4 hours difference, n = 23; and 24 hours difference, n = 41) the total motile sperm counts increased significantly (3.2 [0.6 to 7.9] versus 8 [0.4 to 48] and 4 [0.2 to 13] versus 4 [0.1 to 101], respectively). In all groups, pooling sequential ejaculates significantly increased the total motile sperm counts, over and above that of the first ejaculate, by 49% in the normospermic group, 95% in the asthenospermic group, 67% and 75% in the oligospermic groups (1 to 4 hours and 24 hours difference, respectively), and 233% and 139% in the oligoasthenospermic groups (1 to 4 hours and 24 hours difference, respectively). Conclusions: Sequential ejaculation may overcome the impaired sperm transport causing low total motile sperm counts observed in some oligospermic and/or asthenospermic men. Most of these infertile men may significantly increase their fertility potential, assessed by the total motile sperm counts, either by pooling sequential ejaculates for IUI, GIFT, and IVF, or by having intercourse every day or even twice a day, at the time of ovulation.