Natural Cycle is exactly what it implies. Using one’s own cycle in conjunction with timed intercourse, intrauterine insemination or therapeutic donor insemination. One may have intercourse every other day starting on cycle day 11 or choose to use an ovulation detection kit to determine the LH (leutinizing hormone surge) and have intercourse 12 hours after the surge and again in 24 hours after the surge. Ovulation usually occurs 24 to 32 hours after the LH surge.