In specialty hospitals, many surgeries involving the reproductive tract are considered emergency surgeries. 

Females   Removal of the ovaries and uterus may be considered for many reasons.  First, when an ovariohysterectomy (or spay) is performed prior to the first heat cycle, the chance of the animal developing mammary cancer is lowered to less than 0.5%.  It decreases the chance of ovarian and uterine cancer and of pyometra, an infection of the uterus.  These surgeries are most commonly done by veterinarians in general practice.  Sometimes this type of surgeries may be referred to a specialist if the patient is geriatric, has other health problems, has a large mass associated with a reproductive organ, or if the patient has a pyometra and is severely ill.  These situations obviously have more risk involved that when the patient is a healthy puppy.

Pyometra.  Pyometra occurs when the uterus fills with pus.  As females age, the endometrium can become cystic and inflamed, which may render the uterus more likely to become infected.  If the cervix remains open, drainage can occur from the uterus.  If the cervix is closed, then the pus-filled uterus can cause animals to become ill.  The kidneys may be affected by the changes in blood flow and by the toxins produced by the bacteria in the uterus.  These animals may become septic, a condition where infection becomes overwhelming to the body.  It is important to treat a closed pyometra as soon as possible.  Signs of pyometra include depression, vaginal discharge, vomiting, increased water consumption, increased urination, and inappetance.  Bloodwork often indicates the severity of the infection that is present, and evaluates the function of the kidneys.  Radiographs and/or an abdominal ultrasound may be performed to look for a distended uterus.  Treatment may be medical or surgical.  Medical treatment may be used initially if the patient is a valuable breeding animal.  However, medical therapy takes about 48 hours for improvement to occur; in very sick animals, this may be too long to wait.  In most cases, immediate surgery is recommended to remove the infected uterus. 

Stump pyometra and uterine remnant syndrome.  Stump pyometra occurs in spayed females if ovarian tissue is left inside the body at the time of the spay.  This tissue produces hormones that cause the uterus to continue secretions of the lining and can lead to pyometra.  The treatment for this problem is to remove the stump and whatever ovarian tissue that may remain in the patient.  Ovarian remnant syndrome may also occur in these patients, where ovarian tissue that remains in the body may continue to produce hormones and the patient still comes into heat.  Mammary masses may also be associated with remaining ovarian tissue.

Other conditions of the uterus.  Uterine prolapse may occur during or after labor.  The uterus protrudes from the vulva.  The uterus may be replaced, or it may need to be removed depending on its condition.  Uterine torsion may occur in pregnant animals, where the uterus twists upon itself. 

Mammary glands. Mammary glands can have several problems associated with them.  Cancer of the mammary glands is common.  This can almost completely be prevented by having your pet spayed before the first heat cycle; this reduces the chance of mammary cancer to less than 0.5%.  After the first heat cycle, the chance goes up to 8%; after the second, to 26%.  Unspayed cats have an even greater risk of developing mammary cancer.  Mammary cancer may be benign or malignant.  Radiographs of the chest are recommended if mammary masses are found to look for metastasis of cancer.  In dogs, removal of the affected gland or the lump itself is recommended.  If multiple masses are present thoughout a mammary chain, then the entire chain may be removed.  Cats more often have malignant mammary tumors.  In cats, radical mastectomies are recommended. 

Dystocia.   Dystocia occurs when any abnormality occurs during delivery of puppies or kittens.  Dystocia occurs when the mother appears systemically ill, if strong frequent contractions fail to produce a puppy in 30 minutes, if weak straining fails to produce a puppy in 2 hours, or if more than 4 hours has elapsed since a puppy has been born and more puppies are know to be present.  Dystocia may be caused by an abnormally large fetus or a fetus with a large head, an abnormal birth canal in the mother, poor uterine contractions