How Long Are Cats Pregnant? The Honest Answer Is a Range

Ask a vet and you will hear "about nine weeks." Ask the studies and you will get 57 to 72 days, with most litters arriving between day 63 and day 67. Both answers are right; they measure different things. The short version is at the top of this page and the reasons the number moves are underneath, along with the signs to watch for, the tests a vet actually uses to confirm a pregnancy, what to feed, and the handful of moments that mean a phone call.

The gestation answer: 63 to 65 days, counted from mating

Three published studies measured feline gestation in real litters rather than quoting each other. A US research colony (15 pregnancies) averaged 66.9 days, range 62 to 71. A Dutch questionnaire study of 197 queens found a mean of 65.3 days, range 57 to 72. The largest, a UK study of 1,056 pedigree litters across 14 breeds, found a mean of 65.1 days, with the length varying significantly between breeds. A 2006 review of the literature puts the average at 65.6 days and the widest reported range at 52 to 74.

Two things move the number. Bigger litters arrive sooner: both the Dutch and the UK studies found that gestation shortened as litter size grew. And the count starts at mating, which is not always one date: queens often mate several times over several days, and a study of daily ultrasound found the first mating was the true start in about 92% of pregnancies, not all of them.

The consumer guides round this to a slogan, and they do not agree with each other. Cats Protection says 63 days on its web page and 63 to 65 in its printed guide; International Cat Care says 63 to 65; Merck's owner manual says 60 to 65. VCA, one publisher, gives three different ranges on three of its own pages (60 to 67, 64 to 71, 58 to 70), none citing a study. And if you have read "58 to 72 days" attributed to Merck's gestation table: on the table itself that footnote sits on the dog row; the cat row reads a flat 65.

Why is the cat's range tighter than the dog's, at least in principle? Cats are induced ovulators: mating itself triggers the hormone surge that releases the eggs, and ovulation follows within about a day. In dogs, a mating date and an ovulation date can sit days apart, which is why the dog literature needs two counting frames. In cats the two dates stay close, so "days from mating" is the working frame in every study above.

In weeks and months: 63 days is nine weeks exactly, which is where "nine weeks" comes from. "About two months" is the conversational version and nothing more precise than that. If you want the week-by-week timeline of what is happening inside her, our cat pregnancy stages page lays out the anchor days the ultrasound studies actually measured.

Signs your cat is pregnant, roughly in order

Early pregnancy is nearly invisible. The fertilized eggs implant toward the end of week two, and until then nothing on the outside changes. Her heat cycles may even continue briefly, and if she mates again a single litter can carry more than one father.

• Her heats stop, and her nipples "pink up." The first sign most owners notice: the nipples become more visible, pinker, and slightly larger. Cats Protection's web page puts this around week three; the same charity's printed guide says "after about four weeks." Take it as the second half of the first month rather than a fixed day.
• Appetite and weight. From around four weeks she gains weight and her appetite usually rises. Some owners report a cat going off her food or vomiting around this time, sometimes called "morning sickness." That is a single charity's description written by analogy with people; no feline study has examined it, so treat it as an observation, not a rule. A cat that is not eating at all belongs at the vet (our not-eating guide explains why cats cannot afford to fast).
• A rounder belly, then movement. By week five the weight gain is visible; by week six she is very hungry, her belly is unmistakably round, and you may see the kittens move. A vet with a practiced hand can often count them by feeling her abdomen around this point. Do not try this yourself.
• Nesting. In the final two weeks, typically from week seven, she starts looking for a safe, quiet place to give birth: a wardrobe floor, a box, the back of a closet.
• The last stretch. In week eight the nipples are quite swollen and she grooms her belly so much that some fur may come away. In week nine a small amount of clear or red-tinged discharge from the vulva is described as normal by both UK charities. Brown, green, black or pus-colored discharge at any point in pregnancy is not, and neither is abdominal pain or a fever: those three are VCA's own list of signs of miscarriage or infection, and they mean a call.

One sign that gets misplaced: vomiting, trembling, hiding and refusing food are described by Merck as signs of the first stage of labor, at day 63 to 65 or so, not of early pregnancy. In the last 24 hours before birth she usually stops eating, and her rectal temperature may drop below 100°F (37.8°C). Everything from that point onward is on our cat giving birth page.

How a vet confirms it, and how early each method works

There is no over-the-counter pregnancy test for cats. What exists is the vet's toolkit, and each tool has a window.

The ultrasound days come from two small research studies that scanned queens daily: one saw the gestational sac at day 10 and could measure the embryo from day 18; the other saw the embryo at day 15 or 16, limbs at day 19 and the stomach at day 26. Those are laboratory schedules, not what a routine appointment promises; the charities' practical advice is that a vet can confirm a pregnancy by ultrasound at about four weeks, which the numbers support with room to spare. A fetal heartbeat settles around 250 beats per minute in mid-pregnancy in the one study that tracked it, in five cats.

The relaxin test is a point-of-care kit built for dogs and used off-label in cats. In the University of Florida study, it first turned positive at day 20 and was positive in every pregnant cat from day 29 onward. Its specificity was 95.9%: three false positives, two of them in cats with large ovarian cysts. The abstract does not say how reliable it is between day 20 and day 28, so we do not either.

X-rays and ultrasound do different jobs. In a study of 24 purebred queens, radiography counted the fetuses accurately but could not predict the day of birth, while ultrasound measurements of the fetal femur could. The two sources disagree on when the skeletons show: VCA says around day 45, Merck says more than 55 days after breeding; the later figure is the more conservative. Progesterone monitoring appears in the research literature too, as a research tool rather than a routine test, so it is not in the table.

The three trimesters, in one paragraph

Feline pregnancy is nine weeks, so a "trimester" is three weeks, and only VCA's nutrition page uses the word at all. As a rough convenience: the first three weeks are the quiet ones (implantation, the first hormonal changes, the pinking); the middle three are when a vet can confirm it and the weight comes on; the last three are nesting, mammary development and the countdown to labor. The week-by-week page replaces this paragraph with the measured anchor days.

Feeding and care through the pregnancy

• Switch to kitten food, early. Both International Cat Care and VCA say the same thing: from the moment you know she is pregnant, feed a growth diet (kitten food) or an all-life-stages diet, and keep her on it until about a month after the kittens are weaned. In the US, veterinary nutritionists point to diets that have passed an AAFCO feeding trial for gestation and lactation.
• How much more. The figures depend on the window being described. VCA's nutritionists put her requirement at about one and a half times her pre-pregnancy level during pregnancy, rising past twice that by weaning. Merck's figure is 25% more food, but specifically during the last three weeks, and two to three times normal while nursing. The two are not really in conflict: early pregnancy needs little extra, the final third and lactation need a lot.
• Meals, not a free-for-all. VCA recommends meal feeding to control weight gain, and several small meals a day in the final trimester, when a belly full of kittens leaves less room for a full stomach.
• No supplements. Merck and VCA agree: a complete and balanced diet, and no calcium or vitamin supplements. The mechanism matters here: excess calcium in pregnancy suppresses the parathyroid hormone that manages calcium after birth and raises the risk of eclampsia, a dangerous calcium crash in a nursing queen.
• Parasite products are a label question, not a yes or no. We read three US labels. Plain selamectin (Revolution) states it was tested in pregnant and lactating cats; the newer selamectin-plus-sarolaner product from the same company (Revolution Plus) states its safety has not been evaluated in pregnant cats; Frontline Plus for Cats is labeled for pregnant and lactating queens. Same shelf, opposite answers, so hand the box to your vet. UK, Canadian and Australian labels for the same brands can differ, and we did not read them. Our flea guide and worm guide cover the products themselves.
• Vaccines: ideally before, not during. The 2024 WSAVA guidelines are explicit: pregnant queens should not be given live attenuated vaccines, inactivated vaccines are considered safer, and the best plan is to vaccinate before she becomes pregnant. The 2020 AAHA/AAFP guidelines say the same for the US. Our vaccination guide covers the schedules.
• Handling and housing. From about four weeks, pick her up only if she likes it, and support her properly; both UK charities say to ask your vet how. Set up the kittening box in a quiet room with her food, water and litter tray nearby. Merck adds one line breeders know: in the second half of pregnancy, keep her away from other cats where you can, to reduce exposure to infections, especially the respiratory ones.

False pregnancy: when everything looks right and nothing is there

Because mating is what triggers ovulation in a cat, a queen can ovulate, fail to conceive, and still go through the hormonal aftermath of a pregnancy. Merck calls this uncommon in cats. The signs are the pregnancy signs: mammary development, sometimes milk, and behavior changes up to and including acting as if she has delivered. A vet rules out a real pregnancy with a history, an examination, and an x-ray or ultrasound; the relaxin test helps too, because a false pregnancy has no placenta to make relaxin.

There are two clocks here, and websites usually blur them. The visible signs typically resolve on their own in one to three weeks, which is why Merck says treatment is often not recommended (the possible drugs have significant side effects). The underlying hormonal phase, diestrus, lasts about 40 days in a queen that ovulated without conceiving, against about 60 in one that did. Two practical lines from the same source: do not milk out the glands, which only stimulates more milk, and if it keeps happening, spaying ends it. No feline study has measured how often false pregnancy occurs; the "uncommon" is the manual's word, not a rate.

When to call the vet during a pregnancy

• Discharge that is brown, green, black or pus-colored, at any stage, or abdominal pain, or a fever: VCA's list of the signs of miscarriage or infection.
• She is unwell, off her food for more than a day, or you are simply worried: both UK charities say to call, and the sick-cat symptoms guide explains what "unwell" looks like in an animal that hides it.
• Past the due window. Cats Protection's line: most cats deliver in week nine, some run into week ten, and if there is still no sign of kittens at the end of week ten (day 70), call.
• Labor that stalls. The published thresholds for strong, unproductive straining disagree: VCA says twenty minutes, Cats Protection thirty, Merck one to two hours. This site's posture is that the shortest figure is the one to act on. Difficult birth is rare in mixed-breed cats and less rare in pedigree ones: in a UK study of 118,168 queens seen in emergency practice, 0.93% presented with dystocia, purebred queens had two and a half times the odds and flat-faced breeds more than three times. The full list of birth-day thresholds, and what happens at the clinic, is on the cat giving birth page.

What to take away

• Measured studies put feline gestation at a mean of 65 to 67 days with a range of about 57 to 72; the everyday answer is 63 to 65 days, or nine weeks, counted from mating.
• Bigger litters arrive sooner, and one publisher (VCA) gives three different ranges on three pages, which is why "how long" gets so many answers online.
• The first sign is usually the nipples pinking up in the second half of the first month; a visibly round belly and kitten movement follow by week six, and nesting begins in the final two weeks.
• A vet can see a gestational sac on ultrasound from day 10 to 11 in research conditions, confirm a pregnancy reliably at about four weeks, and count kittens on an x-ray from around day 45 to after day 55 depending on the source.
• The relaxin blood test first turns positive at day 20 and was positive in every pregnant cat from day 29 in a 162-cat US study, with a specificity of 95.9%.
• Feed kitten food from the day you know, up to a month after weaning; skip calcium supplements (eclampsia risk); no live vaccines in pregnancy per the 2024 WSAVA guidelines; and a brown, green or pus-colored discharge at any stage means a call.