There are many reproductive diseases that can affect the female cat. The most common of these diseases are discussed below.
Abnormal or Difficult Birth (Dystocia)
Many factors can cause a difficult birth (dystocia), including uterine problems, a too small birth canal, an oversized fetus, or abnormal position of the fetus during birth. One of the more common situations in cats is a partially delivered kitten. Unless the head of the kitten is sticking out (so that the kitten can breathe), it must be delivered within 10 to 20 minutes or the kitten will die.
Dystocia should be considered in any of the following situations: 1) cats that have a history of dystocia; 2) strong contractions for more than 1 to 2 hours with no birth; 3) a resting period during labor that lasts more than 4 to 6 hours; 4) obvious pain or illness in the mother (for example, crying, licking, or biting the vulva); 5) abnormal discharge from the vulvar area (for example, fresh blood or dark green discharge before any kittens are born); or 6) kittens are not delivered within 24 hours after a drop in rectal temperature below 100°F.
Once the cause is determined, the appropriate treatment can be selected. X-rays or ultrasonography can show how many fetuses are present. Medication can sometimes help the labor progress if the mother and kittens are still in stable condition and there is no obstruction. Surgery (cesarean section) is performed if the mother or kittens are not stable, there is an obstruction, active labor is prolonged, medications do not work, or the fetuses are not able to be delivered naturally.
False Pregnancy (Pseudopregnancy)
False pregnancy (pseudopregnancy) is uncommon in cats but occurs when they have been induced to ovulate but did not conceive. There may be mammary development with milk production. Cats also often exhibit behavior changes (for example, acting as if pregnancy and delivery have occurred). Your veterinarian will eliminate the possibility of true pregnancy by the medical history, physical examination, and x-rays or ultrasonography. When it does occur, treatment is often not recommended because the condition usually ends on its own in 1 to 3 weeks, and possible treatments can have significant side effects. You should not milk out the mammary glands, because this will only stimulate production of more milk. If your cat has repeated episodes of pseudopregnancy, spaying will stop it from happening again.
Follicular cysts are fluid-filled structures that develop within the ovary and result in prolonged secretion of estrogen, continuous signs of estrus (heat), and attractiveness to males. Ovulation may not occur during this abnormal estrous cycle. Follicular cysts should be suspected in any female cat continuously showing signs of estrus (heat) for more than 21 days. This can sometimes be difficult to differentiate from normal, frequent cycles. The condition is diagnosed through laboratory tests or ultrasonography. The most commonly recommended treatment is spaying (removal of the ovaries and uterus), which is curative. If the cat is to be bred, administration of drugs that affect ovulation might resolve the condition.
Overgrowth of Mammary Tissue (Mammary Hypertrophy)
Mammary hypertrophy is a benign condition characterized by rapid abnormal growth of one or more breasts.. It occurs most often in young, cycling, or pregnant females, but it can be seen in non-neutered females of all ages, in older, non-neutered males, and in neutered males after treatment with progesterone. This condition is due to the effects of progesterone and is not cancerous. The most commonly recommended treatment is spaying (surgical removal of ovaries and uterus), although spontaneous remission can occur. Spaying prevents it from happening again.
Mastitis is inflammation of the mammary gland(s) after giving birth. It is uncommon in cats. Mastitis is usually caused by a bacterial infection. Risk factors for developing mastitis include poor sanitary conditions, trauma inflicted by offspring, and whole-body infection. Mastitis may involve a single gland or multiple glands. Milk may appear normal or abnormal in color or consistency. The affected glands may be hot and painful. If mastitis progresses to a generalized infection, signs of illness such as fever, depression, poor appetite, and lethargy may be seen. The mother may also neglect her kittens. In cats with longterm inflammation, the only sign may be failure of kittens to thrive.
The disease is diagnosed based on the cat’s medical history, physical examination, and evaluation of milk from each gland. Mastitis can be treated with appropriate antibiotics. Cats that are dehydrated or in shock may require intravenous fluids. Warm compresses can be applied to the affected glands 4 to 6 times daily, and the kittens should be encouraged to nurse from these glands. If the mammary gland develops an abscess (a pocket of pus and infection), your veterinarian may need to drain it surgically.
Mastitis that is not due to a bacterial infection can occur when the kittens begin to eat solid food. The affected glands are warm, swollen, and painful to the touch, but the mother is alert and healthy. Warm compresses can be applied to the area 4 to 6 times per day. Reducing the mother's food to pre-pregnancy amounts can help reduce milk production. You will also need to provide the kittens with water and kitten food.
Metritis is inflammation of the uterus and may occur after pregnancy. Factors such as prolonged or difficult delivery and retained fetuses or placentas might lead to metritis. A bacterial infection is typically present. The primary sign of metritis is pus-like discharge from the vulva. Female cats with metritis are usually depressed, have a fever, and may neglect their offspring. Kittens may become restless and cry incessantly. The infection is diagnosed through abdominal physical examination, x-rays, ultrasonography, and laboratory tests. Treatment includes administering intravenous fluids, supportive care, and appropriate antibiotics. Your veterinarian may also prescribe prostaglandin F2α to help remove any retained fetuses or placentas. Severely ill cats may need to be spayed once they are stable enough for anesthesia. If future litters are not desired and the infection is not severe, the mother can be spayed after she finishes nursing her kittens.
Ovarian Remnant Syndrome
Ovarian remnant syndrome is caused by ovarian tissue that was left behind in a cat that has been spayed. Affected cats resume estrous cycles at variable lengths of time after surgery. This is a complication of the surgery. To diagnose this disorder, the veterinarian should see the cat when it is showing signs of heat. Laboratory tests can confirm the diagnosis. The remaining ovarian tissue must be surgically removed.
Pyometra is a bacterial infection of the uterus due to hormonal changes in unspayed cats. It is less common in cats than in dogs. The signs are variable and include lethargy, poor appetite, increased thirst and urination, and vomiting. When the cervix is open, a discharge of pus, often containing blood, is present. When the cervix is closed, there is no discharge and the enlarged uterus may cause abdominal enlargement. Signs can progress rapidly to shock and death.
The infection is diagnosed by physical examination, determination of the nature of the discharge, abdominal x-rays, ultrasonography, and laboratory and blood tests. Removal of the ovaries and uterus (spaying) is the best treatment in most cases. The bacterial infection is responsible for the illness and will not respond until the pus-filled uterine fluid is removed. Before surgery, the cat may need to be stabilized with intravenous fluids and antibiotics. Antibiotics are continued for 7 to 10 days after surgery. The surgery is curative.
Medical treatment may be considered for valuable breeding females that are not severely affected and that have an open cervix. Medications used as an alternative to surgery have side effects, including an increased risk that the uterus could burst in animals with a closed cervix. These medications are often administered in the veterinary office because they can also cause side effects in people. Of cats that respond to medical treatment, 70% may still be fertile. Recurrence is common. These cats should be bred during every subsequent heat cycle until litters are no longer desired, and then the cat should be spayed.
For More Information
Also see professional content regarding reproductive diseases of the female small animal Reproductive Diseases of the Female Small Animal .