Dystocia can also be classified according to whether it arises from obstruction of the birth canal or a functional deficiency of the uterine muscle. Obstructive dystocia is caused by disproportion between the size of the kittens and the maternal birth canal. Factors resulting in an inadequate size of the maternal birth canal may include disorders of the maternal skeleton healed pelvic fractures , the pelvic soft tissues severe constipation , or the uterus itself uterine torsion or rupture.
Foetal causes of obstructive dystocia may result from malpresentation, severe foetal malformation eg, hydrocephalus, Siamese-twins , foetal oversize or foetal death. Functional dystocia is usually termed inertia and can be either primary or secondary.
Primary inertia is by far the most common cause of dystocia in cats. It is seen when the uterus produces none, or only weak, infrequent contractions and there is a failure of expulsion of normal kittens through a normal birth canal.
Primary inertia may be related to stress, old age, obesity, ill health or the administration of certain drugs. It has been suggested that very small or very large litters may result respectively in inadequate or excessive uterine distension, and that this may result in primary inertia.
However, recent work found no difference between the litter size of cats with dystocia due to primary inertia and the litter size of cats with dystocia for other reasons. In this condition extreme apprehension during the first stage causes all progress to cease.
The affected cat is markedly and vocally distressed, crying constantly and demanding attention. She may be positively hysterical, and in such cases, immediate relief may be obtained by the use of tranquillisers. In an emergency, this would be administered by a veterinary surgeon by injection, but if the cat in question is known to behave in this fashion, the breeder may be equipped with tablets which can be given by mouth at the start and will be equally effective.
Abnormalities of the first stage can include all forms of primary inertia, and occasional rare disorders, such as torsion or rupture of the uterus. These latter two conditions can result in major emergencies in late pregnancy or first stage labour. Torsion implies a twisting of the uterus, cutting off its blood supply, and making delivery of the contained foetus or foetuses impossible.
It also causes what is quite obviously an acute emergency with a very ill and shocked cat. Torsion is usually presumed to have occurred during jumping or some violent movement which imparts a swinging motion to the heavily gravid uterus. Rupture is more usually the result of an accidental blow from a vehicle or other violent trauma, or can occur from violent straining upon a complete obstruction. A rupture occurring at the time of parturition will give rise to the same signs of acute emergency as a torsion.
It has been known for rupture to occur early in pregnancy and for the foetus es to continue to develop outside the uterus in the maternal abdominal cavity. In these cases, the placenta becomes attached to one of the abdominal organs but it is unusual for such foetuses to develop to full term and, of course, impossible for them to be born without an abdominal operation. Secondary inertia arises after prolonged second-stage labour, and may be associated with obstructive dystocia, muscle fatigue, or excessive pain.
Interrupted labour, as already described, is definitely not an inertia, as the cat is manifestly normal, labour recommences normally, and kittens are born alive and normal. An important point of difference between the two is that secondary inertia follows previous difficulty or delay and the cat is often restless and exhausted.
Foetal malpresentations, malpositions and malpostures may all lead to dystocia. Presentation indicates which way round the foetus is coming ie, head or tail first , position indicates which way up it is ie, rotated or unrotated and posture indicates the placing of the head and limbs ie, extended or flexed.
Some people believe that foetal malpresentation in cats rarely causes dystocia, except when combined with other problems such as poor cervical relaxation or relative foetal oversize. However, others have found foetal malpresentation to be the most common cause of dystocia of foetal origin, while relative foetal oversize was very rare. Posteriorly presented, or tail-first, kittens occur quite frequently, so much so that this could almost be considered a normal presentation, often causing no delay in birth.
If, however, the first kitten comes tail-first there may well be delay owing to the absence of the wedge-shaped head pushing behind the fluid-filled membranes. The kitten is usually passed eventually. However, it does have an increased risk of drowning in its own foetal fluids if the time from placental separation to when its nose is free from its membranes is too prolonged.
Malposition usually occurs when a kitten has died in utero prior to rotation. It is uncommon except in cases of illness, infection or prolonged delay in a late-coming foetus. The presence of a dead foetus within the maternal pelvic canal can, in itself, result in functional or obstructive dystocia.
Malposture is of most importance in relation to the position of the head. Brachycephalic cats may have difficulty at the point where the foetal head first engages the opening of the maternal pelvis. The lack of a wedge-shaped muzzle increases the risk of the head becoming deflected to one side, downwards between the forelegs, or onto the chest.
Occasionally, one or both forelegs may lie back along the body, and in posterior or tail-first presentation one or both hind legs may be retained forwards alongside the body to give the breech posture. All of these situations may give rise to either a temporary delay and necessitate extra efforts by the cat or, at worst, result in complete obstruction.
A late manifestation of inhibitory hysterical behaviour may cause delay when the kitten is already through the maternal pelvis and protruding through the vulva. This may cause some pain, so at this point, the cat appears to give up trying and waits for, or demands, help. If this is not immediately forthcoming, the particular kitten involved may die, especially if it is coming tail first. The above was a rather daunting, but by no means exhaustive, list of what can, but rarely does, go wrong.
Breeders or owners may want to know what can be done to recognise trouble early and how it can be avoided or overcome. It cannot be too firmly stressed that a normal cat needs no intervention. The good midwife is essentially a good and unobtrusive observer until trouble occurs. Midwives should have provided, as far as possible, the ideal kittening bed which should be warm, comfortable and safe, but should also be observable, ie, a happy medium between confinement and relative freedom within the confined area.
During the first stage of labour, they may need to provide either moral support or remain unobtrusive as dictated by events. They should have at their fingertips a history of any previous births by the cat in question and, if possible, information relating to earlier generations and related animals. They should have observed the changes during pregnancy and be aware of the degree of abdominal distension, amount of fluid, and perhaps have a rough idea of the number of kittens to be expected.
Facilities for help or examination should be at hand if needed convenient table, access to running warm water, soap and towel. An internal examination is resented by most unsedated cats and should not be undertaken by the unskilled. If problems are anticipated the veterinary surgeon should have been alerted and given the probable parturition date before the event and informed of the start of labour so that if a call for help becomes necessary it is expected and can be promptly answered.
Apart from the value of observations and knowledge of the behaviour of the cat, breeders can, and in some cases must, be responsible for the treatment of some parturition problems. The secret, if there is one, of the recognition of trouble lies mainly in the recognition of delay.
The hysterical dependent cat is obvious enough and easy enough to deal with, provided the necessary tranquilliser is at hand. Identification of delays later in the course of kittening will again involve observation of behaviour. In the case of the normal interrupted labour, it will be evident that the cat is in no distress, has a normal appetite and is perfectly happy with the kittens already born.
Straining in the course of a normal parturition, while it may or may not be vigorous, is clearly productive in moving the kitten along and does not appear to give rise to pain.
Obstruction, on the other hand, shows as a cat that strains without producing any results, may pant, cry, or appear exhausted, is restless and unsettled, and finally desists in an attempt to recover sufficient strength for a further, although decreased effort.
This is the cat that requires help. Feeling from the outside around the perineal area under the tail will indicate if a kitten is already through the pelvis, and a view of nose or feet and tail at the vulva indicates that birth must be imminent if the kitten is to live. If no progress is being made and the kitten is clearly visible, it is up to the breeder to give immediate help since, unless the veterinary surgeon literally lives on the premises, veterinary help may not arrive in time for that particular kitten.
If nothing can be felt at the vulva and the hold-up is evidently further forward, then it is time to send for professional help. Diagnosis and treatment of the serious dystocia must be in the hands of the veterinary surgeon. Because of the small size of the cat, manipulative correction of malpostures from within the vagina is rarely possible and is, in any case, a job for skilled hands. To compensate for this, manipulation from outside the abdomen can often correct a malposture such as a laterally deflected head; again professional skill is needed.
Often, in any real hold-up, a Caesarian operation is the preferred method and provided that the cat is neither desperately ill nor very exhausted, it is a safe and routine procedure. The case where the breeder has to help is that of the cat who gives up trying with a kitten hanging visibly from her vulva. If it is coming head first, the first urgency is to clear the membranes away from its nose and mouth to allow breathing to take place.
This will stop when she gets pregnant. It might not be easy to tell under a layer of dark fur, however. Vomiting: Morning sickness is common for both humans and cats. Weight Gain : Especially later on in the gestation period, owners will often notice a two- to four-pound weight gain.
Longer Sleep Periods : Your cat will want to stay asleep for longer periods of time. Affectionate Behavior: Many pet owners say that they notice an increase in affectionate behavior.
You may notice your pet seeking out your attention more frequently. This is due to hormonal and neurological changes. Nesting Behavior : Cats prepare for birth by finding secluded, quiet places to have their litter. Your cat may even start arranging blankets or being feisty with other animals about her space. This distortion may be harder to see on overweight cats.
Nausea and vomiting may initiate food refusal during this time. Do not push on or touch her tummy as this may affect the growing kittens. Always ensure a cat has fresh water available, and set her feeding and drinking bowls on the ground for easier access as jumping up may be difficult for her and could hurt the kittens. Week 6: Affectionate, frequent purring Cats are known to become more affectionate. Pregnant cats purr more frequently during the final weeks.
Felines can be aggressive or intolerant of other pets in the household. Her appetite will increase again during this time. The best food for pregnant foster cats is kitten food as it contains a high volume of calories. Week 8: Nesting Two weeks before a feline delivers kittens she will begin nesting. A cat starts looking for quiet, warm, safe places to settle into for labor and the birth.
To minimize her nesting choices, keep doors to rooms, closets and cupboards closed. Leave large, cleaned cardboard boxes lined with soft newspaper, paper towels or a washable blanket in a convenient, wind-free, pet-free, low-light areas in the house. Week 9: Kittens A pregnant cat may refuse food as she enters the final stage of gestation in week nine. Kittens usually arrive between 63 and 67 days , or nine to nine-and-a-half weeks.
Cats can deliver kittens without human interference. Always consult the shelter, rescue group and veterinarian about what to expect, steps to take in an emergency, and who to contact if help is required.
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