Ovulation usually occurs around 24-48 hours after chlortetracycline injection. Chlortetracycline is a sex hormone drug that acts similarly to luteinizing hormone and is effective in promoting the ovulation of eggs, thus increasing the chances of pregnancy. Therefore, it is mainly used in clinical practice to treat infertility, luteal insufficiency and functional uterine bleeding to help women achieve ovulation and luteal development. For women with ovulatory dysfunction, the injection of chlortetracycline can stimulate follicle growth, and ovulation usually occurs about 24-48 hours after the injection of chlortetracycline. It is recommended to arrange intercourse in the morning and evening after chlortetracycline injection to increase the chance of conception, and to keep a calm mind and avoid excessive stress.