You can arrange for intercourse on the day of the injection and on the second day after the injection, or if you are energetic, you can arrange for intercourse on the first day after the injection. If the follicles are well matured before the injection, the luteinizing hormone in the body will rise more obviously, which will be conducive to the rupture of mature follicles, it is possible that the follicles will rupture on the same day of the injection, and most of them will rupture in 36 hours after the injection. The timing of intercourse is based on when the follicle ruptures, so scheduling intercourse on the day of the injection and once on the second day increases the chances of a successful pregnancy. It is also necessary to have intercourse 2-3 days before the egg breaks, as prolonged intercourse will affect the survival rate of sperms and reduce the probability of successful fertilization. If you have any other questions, please consult your doctor.