The countdown is almost over and you are so excited to see what the kittens will look like, what their colors will be, and to cradle the precious little ones in the palm of your hands. But that was five days ago and your cat seems to have other plans. She doesn’t seem to be in any hurry to have her kittens. She is taking her sweet time…and it is driving you nuts!
The time it takes for kittens to develop in their mother’s uterus or womb from conception to until they are ready for birth is called the “gestation period”. This takes an average of 63 to 65 days. But in cats this period can be very variable. It can be as short as 56 days to as long as 72 days. The reason for this wide range of values is because of the nature of female cats being “induced ovulators”.
Induced ovulator simply means that the female cat will release an egg from its ovary only after she has mated several times with the male cat. Friction from the male’s penis is the required stimulus for an egg to be released from the ovary of the female after which it will meet the male’s sperm to be fertilized. Ovulation requires at least 4 matings, with the average being 8 to 12 matings over the course of several days.
What Causes Pregnant Cats To Be Overdue Giving Birth?
For majority of the time, the problem is not really that the pregnant cat is overdue giving birth but that there is a miscalculation of the kitten’s birth date because of the cat’s very variable gestation period as explained above. Since multiple matings are required for ovulation, it is difficult to pinpoint which particular mating induced the release of the egg from the ovary, its subsequent fertilization and implantation in the womb. If the start date of the gestation period is not accurately known then it follows that the due date can, at best, only be estimated.
To make this difficult situation worse, some cats have long heat periods, sometimes as long as 21 days. During this period she will stand to be mated by the male. When mated early in her season, she will not yet ovulate as the egg in her ovary is not yet “ripe”. Only later in the period will a mating cause her to release her egg. If the owner observed the mating happened early on and assumed this as the start date of the gestation period then the approximation of the due date will be way off the mark! Even more problems arise in this approximation of due date if the cat got outside and became pregnant by accident and the owner has no idea when the cat mated and only noticed the cat being pregnant when she started showing an enlarged belly.
Other factors that may cause a cat to be overdue giving birth should also be considered. The process of birth may be described as a coordinated effort between the mother and the fetus. Giving birth does not solely involve the mother. The fetus, as well, contributes to the initiation of labor. It is believed that when the fetus senses a cramped condition in the uterus or a diminished nutrient supply as multiple fetuses grow bigger, it releases the hormone cortisol. This hormone will cause another hormone called estrogen and a substance called prostaglandin to increase in the mother’s womb which starts the process of labor. Often in dogs, and occasionally in cats, it is observed that the gestation period of singletons are longer. A singleton fetus has the entire uterine space to itself and do not have to compete for nutrients with other fetuses so they may stay inside their mother’s womb longer.
The fetus is not the only source of cortisol but when a fetus dies inside the womb there could be a drop in the levels of cortisol that may contribute to a delay in the birth process. Also, a fetus rotates on the long axis of its body before its head portion reaches the mother’s pelvis to mechanically stimulate uterine contractions. A fetus that has died before this rotation and engagement of the pelvis could occur may likewise contribute to delay in the onset of labor.
Sometimes, the problem lies with the mother cat herself. She may be unable to give birth by natural means. She may have a nerve damage making her uterus weak and unable to contract sufficiently for normal labor to start. Other maternal factors contribute to this weak contractility of the uterus like old age, too young female that the pelvic canal is not well developed yet, malnutrition, stress, obesity, ill health, genetics and certain drugs. Cats are also broadly divided into 2 personality types: the calm stoic cats and the dependent hysterical ones. A calm cat may deliberately stop her labor if she senses a stressful environment with lots of people around. A hysterical cat may also postpone her labor when her owner is not around to give her reassurance.
Potential Problems That Arise When Birth Is Overdue
When a pregnant cat is overdue giving birth, the kittens inside her continue to grow bigger every day and may become too big to pass through her birth canal. This results to a condition called “dystocia” or difficult birth and may require a Caesarian Section (C-Section) to take out the kittens. Some mother cats may develop irregular heart rates when overdue.
When you have a cat that you suspect is overdue always watch out for vaginal discharges with no signs of the beginning of labor contractions. This discharge may be fetal fluid and if labor does not begin in a short time, the kitten inside might die or may be already dead. Premature rupture of fetal membrane and release of fetal fluids before onset of labor will also pose a problem in that the fluid pressure is one factor to help physically push the fetus out during birth. Loss of this fluid pressure may result to a difficult birth process. If you observe this or the mother cat is getting weak, bring her to the veterinarian immediately.
How To Be Able To Estimate Kitten Birth Date With More Accuracy
The best way is to know the mating dates, if possible the date of the successful mating. This can be achieved with greater accuracy if you restrict mating period to 1-2 days. Afterwards, observe the cat for signs that she has released an egg. She will stop showing the signs of heat in 1-2 days therefore when you observe that she has gone off heat then you can estimate the start of gestation period as 1-2 days ago.
Another way is to have your cat seen by a veterinarian with experience and equipment who may be able to do any of the following:
- Monitor blood progesterone level every other day through the cat’s mating period. Progesterone is a hormone produced in the cat’s ovaries that increase in concentration in the blood after the ovary releases an egg. The first day the blood progesterone level reads over the normal is usually the one taken the start of the gestation period.
- Palpation is the act of using one’s hands to examine the body, especially while diagnosing a disease or condition. An experienced veterinarian who regularly does palpation on pregnant cats may be able to estimate the stage or weeks of pregnancy by the size of the uterine swelling or the fetal kittens themselves. Remember, however, that this not a very accurate method because when a mother is bearing larger numbers of kittens, the uterine swelling and fetal kitten sizes tend to be smaller than normal.
- The veterinarian can take an abdominal ultrasound as this method can also be used to estimate fetal age and pregnancy stage. The ultrasound can be fairly reliable starting at about 3 weeks of pregnancy and up. At around this time, fetal heartbeat can be seen therefore if the ultrasound shows fetal heartbeat then the kitten must be at least 3 weeks old in the womb. Ultrasonography can also measure the fetal kitten’s “crown-rump length” or the length from the head to the pelvis. Average values for these have been compiled to help approximate the age of the fetus. One limitation of this estimation though is that sometimes the fetus lies in a curled position making the measurement relatively inaccurate. Sometimes it is more accurate to measure fetal kitten’s head diameter as an indication of their age and how many more days they have left to grow in the womb but then again there may be inaccuracies for larger litters with smaller kittens.
- Taking x-rays of the mother cat’s abdomen will show the bones of fetal kittens when they are around 40-45 days old. Therefore, if the bones are seen in x-rays then the fetuses must be approximately 40 days or older. Crown-rump length, as mentioned above, can also be measured on x-rays.
- Another test that can estimate a fetal kitten’s age is called the Relaxin Test. Relaxin is a hormone produced by the placenta around 20-25 days of gestation and can be detected in the mother’s blood using a test kit. A limitation is that some cats may not show adequate levels of this hormone until after 31 days so the test must be repeated if an earlier test turned out negative. Another limitation of the test is that non-pregnant queens may test positive if they have a condition called cystic ovaries.
Inducing Onset of Labor
If you are relatively sure that your pregnant cat is overdue, provide her with a clean, quiet, place for birth; preferably a nesting box or basket with food, water and litterbox within easy access. Depending on your cat’s personality type, either leave her alone and keep watch at a distance or be there with her to reassure her. Stop being overly nervous yourself because cats can sense their human’s mood and it may stress her to delay labor even more.
You can help stimulate labor in the queen by encouraging light physical activity like walking. You may also try applying very light massage with your fingers on her belly in circular motion from chest area down to vulva. Light nipple massage is known to promote uterine contractions in humans by the release of the hormone called oxytocin. It may be worth trying in the queen.
If you have counted 70 days and your queen still is not showing any signs of labor then go and have her examined by the veterinarian, regardless if you still see kitten movements and she looks happy and not showing any signs of distress. Difficult birth should be suspected when more than 70 days have passed from the estimated day of last breeding with no signs of impending labor.
At the veterinarian’s office, a queen with a hysterical personality may be given a tranquilizer to help calm her down so she may proceed with the onset of labor. Then an ultrasound is done to determine if the fetal kittens are still alive by checking for heartbeat and movement. When it is ascertained that the mother and kittens are doing well, a blood sample may be taken to assess again the amount of the hormone progesterone in the blood. Finding higher levels of blood progesterone than a certain amount would indicate that the queen is not yet full term in her pregnancy and labor should not be induced. She should be kept under close observation and progesterone levels measured again in a few hours or a few days after.
If it has been determined with fair certainty that pregnancy due date is past, the mother and fetuses are in good general condition, the birth canal is fully dilated with no constrictions, the kittens are not too large to pass the birth canal and they are in the correct position and presentation, medical management may be started by the veterinarian. To induce contractions in the uterus and begin labor, the hormone oxytocin may be given to the queen by injection.
If however, it is determined that the kittens have become too large to pass normally through its mother’s birth canal, then a Caesarian Section surgery procedure may have to be performed. But this must be done only when it is certain that the kittens are due or past their due dates because if gestation period is miscalculated way off, premature kittens have very low chance of survival outside their mother’s womb. These factors should be discussed between you and the veterinarian so a mutual agreement as what next steps to do can be arrived at.
In general cats do not require much human intervention when giving birth. They are less prone to encounter difficult birth than dogs. But as the human parent of a pregnant queen it is still best if you know when she had mated and approximately when she is due to give birth. This allows you to be able to prepare and, ideally, to be at home when she gives birth to observe her and monitor the birth process from afar or to offer reassurance if she seeks it or help when she needs it. First time mothers, especially young ones, sometimes get confused what to do with the kitten once it is out. Your assistance may be needed to cut the kitten’s umbilical cord and dry the little one. Keep a sterile scissor and thread, along with clean dry towels ready on hand. Read up as much as you can about the cat birth process so you know what to expect.