The speed of follicle rupture is related to the size of the follicle and the hormone levels in the body. If the timing is right, with 10,000U of urotensin, it is possible that the follicle will break within 1 hour. In the natural state, the follicle can rupture spontaneously if the diameter of the follicle reaches 18~23 millimeters, the level of estrogen in the body reaches more than 200 units, lasts for about 48 hours, and the luteinizing hormone reaches 40 IU/L, and lasts for about 36 hours. If the injection of 10,000 U of urotropin coincides with the hormone levels in the body, the follicle may rupture instantly. If the injection is earlier, it may take 36 to 48 hours, or even 72 hours, to rupture. In addition a very small number of women have follicular non-rupture syndrome, even after 10,000 units of urotensin are injected, the follicle may not rupture. It is recommended that patients undergoing ovulation induction therapy follow up treatment as prescribed.