In clinical practice, follicle 22 by 21 refers to follicle 22mm x 21mm, breaking the egg injection is also known as intramuscular injection of chorionic gonadotropin, follicle 22mm x 21mm intramuscular injection of chorionic gonadotropin is generally useful to promote follicle discharge, unless the follicle has been luteinized, which may not be useful.1. The actual fact that 22mm×21mm is a normal sized mature follicle, it is possible that the human chorionic gonadotropin or urea sex hormone and other hormone secretion disorder that promotes follicle discharge leads to untimely ovulation. In this case, follicle 22mm×21mm myeloablative injections with vincristine are useful, and the chances of pregnancy are higher at this time, but you need to check again the next day to determine if the follicle is expelled. 2. If the follicle is 22mm x 21mm, it is useless to inject inject injectable chlortetracycline, it is necessary to treat the follicular luteinization as soon as possible to avoid the seriousness of the disease.