How to Tell if Your Cat Is Pregnant

There are few things cuter than a litter of kittens, those little mewing balls of fluff chasing their tails and pouncing on invisible prey. You can hardly wait until your cat gives birth, but when will that be?

Pregnant grey cat laying on the fabric
Unlike human babies, kittens take just over two months to gestate.
credit: SharafMaksumov/iStock/GettyImages

Unlike human babies, kittens take just over two months to gestate, and it can sometimes be hard to tell exactly how pregnant your feline friend is, or if she's expecting at all. Understanding the cat pregnancy timeline can help you pin down a date when the kittens will enter the world, and know what to expect along the way.

When can cats conceive?

Unspayed female cats hit puberty and can first get pregnant when they are six to eight months old, although this can vary by breed. For example, Siamese and other Oriental breeds reach puberty at about four months, while larger and long-haired breeds, like Persians and Maine Coons, may not be able to get pregnant until they are 18 months old.

Cats go into estrus in a three-week fertility cycle. They go into heat during one week of the cycle. At this time they are ready and willing to mate and may exhibit new behaviors such as unusual cries, rubbing hind quarters against objects, and even spraying urine, which contains pheromones.

This will attract male cats, who will come calling if you let your cat outside. In fact, she may find more than one mate and her litter could be fathered by more than one male cat. Most litters contain three to five kittens.

Cat gestation period

Unlike in humans, cats must actually mate to ovulate and release eggs. They will be fertilized while in the Fallopian tubes, and then the waiting begins. On average, the cat gestation period is 63 days, but this can range from 59 to 72 days.

It's easiest to think of a mother cat's pregnancy in terms of weeks and trimesters. On average, kittens will be born nine weeks after conception, and as in human pregnancies, it's often broken down into trimesters.

The first three weeks

Unless you know your cat mated, you won't initially know she is pregnant — and neither will she. However, she will go out of heat within three days of becoming pregnant, and her behavior will go back to normal. The fertilized egg, called a zygote, begins to divide, and by the sixth day starts to develop a digestive system and placenta forms.

During the second week of pregnancy, both you and your cat still won't be aware a litter of kittens is developing. Occasionally, cats get morning sickness and vomit, or eat less at this stage, but more often this happens in the second trimester.

By the tenth day of pregnancy, the zygotes finally slip out of the Fallopian tubes and into the mother cat's womb. During this week, the embryos grow from a microscopic 1 mm to 5 mm, which is still less than 1/8 of an inch. By the end of the second week, the spinal cord and nervous system begin to form.

Cat pregnancy symptoms

By the fifteenth day of pregnancy, you may finally notice some cat pregnancy symptoms. Purina says her nipples become pinker and larger as they ready for the job of feeding her hungry brood. If you could peer inside your cat by day 17, you would notice the embryos, still less than half an inch long, are beginning to look vaguely kitten-like, with tails.

By the end of the third week, you will finally be able to feel the kittens since they are growing fast, and most of their internal organs have formed. But do this under the supervision of a veterinarian. The embryos are very delicate still, and inexpert poking and prodding could harm them. Your vet can also do an ultrasound at this point to confirm the pregnancy.

The second trimester

By the beginning of the fourth week, cat pregnancy symptoms accelerate. Her nipples grow pinker and elongate as her mammary glands begin to prepare milk. The fur on her chest will thin so that the kittens, born with their eyes closed, will better be able to find her nipples and nurse.

This is the time pregnant cats most often experience morning sickness so you may notice your cat is vomiting or rejecting food. She may also experience changes in taste and want a different food. Now is the time to provide a more nutrient dense food made for pregnant and nursing cats.

By the fifth week, you will start to notice your cat's abdomen bulge to accommodate the quickly growing kittens. Inside, their faces take shape, and their brains accelerate in growth.

Pregnant cat behavior

Signs of pregnant cat behavior increase. She may be slower and more tired as her body changes to accommodate her kittens, each of which has grown to about 2 1/2 inches long by the end of the fifth week. Your normally loving cat may become moody as hormones course through her, although there will be times when she begs for attention.

Your cat will gain one or two pounds during the second trimester as the kittens continue to grow and prepare for life outside the womb. This means your cat's uterus may press on her bladder, leading to occasional accidents. The stress of the later weeks of pregnancy may make her anxious or moody.

By her fortieth day of pregnancy, your vet can X-ray your kitty to see how many kittens she's carrying. This isn't crucial, especially if a trip there will stress her out even more, but it can be nice to know how many kittens are on the way!

The final stretch

By the seventh week, your cat may be extra hungry as the kittens continue to grow by leaps and bounds. At the same time, all those little ones may be pressing on her stomach, making it hard to eat a lot. Encourage her to eat her favorite food and ones that are nutrient dense. Feeding her smaller meals more frequently may help her consume enough nutrition.

During this time, her anxiety ramps up even more and her energy is flagging. She may just want to be left alone to rest. By now, the kittens are fully formed and covered in a thin, velvety fur. By end of the eighth week, the fur will develop the markings the cats will carry throughout their lives.

The kittens are now about 3 ounces each as they enter the final week before birth. Tired as she is, you cat may become restless, pacing around your house. This agitation has a purpose, though. She's looking for a quiet, safe spot to nest.

You can help by creating a comfortable birthing spot for her, lining a box with one open side to use as an entrance with old blankets and towels that you likely will be throwing out after the birth. Of course, mom cats may have their own preferences as to a birthing area, choosing a laundry basket or a closet in which to give birth.

Preparing for birth

By the last week of pregnancy, your cat may be vocalizing more because she is so uncomfortable or in pain. She may begin shedding copiously. Her nipples are at their largest point and may leak milk. About 24 hours before she goes into labor, her temperature drops to 100 degrees, which you can measure with a rectal thermometer if she will allow it.

One to two days before she gives birth, your cat may reject all food and not want to drink. Offer food and water to her, but realize she may not consume them.

Pregnant cat labor signs can include a yellow or reddish discharge, indicating her cervix has dilated. Her contractions will soon begin and will even be visible to you. She will cry and yowl and pace near her nest as the pain ramps up. Stay nearby to monitor the birth, but leave her alone as much as possible.

After an hour or two of labor, the first kitten will be born, followed every 15 to 30 minutes by her litter mates. In just a few days, these blind, wet little creatures start to resemble those tiny mewing balls of fur you envisioned nine weeks ago.