Are there other factors that cause pyometra to develop?
The use of progesterone-based drugs can do this. Estrogen will increase the effects of progesterone on the uterus. Drugs containing both hormones are used to treat certain conditions of the reproductive system. Spaying your female cat will prevent this disease. How do bacteria get into the uterus? The cervix is the gateway to the uterus. It remains tightly closed except during estrus. When it is open, bacteria that are normally found in the vagina can enter the uterus rather easily. If the uterus is normal, the environment is adverse to bacterial survival; when the uterine wall is thickened and cystic, perfect conditions exist for bacterial growth. When these abnormal conditions exist, the muscles of the uterus cannot contract properly. This means that bacteria that enter the uterus cannot be expelled. Pyometra may occur in young to middle-aged cats; it is most common in older cats. After many years of estrus cycles without pregnancy, the uterine wall undergoes the changes that promote
