Most cats start showing signs of pregnancy around the third week after mating. The earliest visible change is a pinkening and swelling of the nipples, often called “pinking up,” which typically appears between days 15 and 21. From there, new signs emerge in a fairly predictable sequence over the course of a 65-day gestation period. Knowing what to look for, and when, can help you figure out whether your cat is pregnant and how far along she might be.
Weeks 1 and 2: Little to Notice
During the first two weeks of pregnancy, most cat owners won’t see any changes at all. Internally, a lot is happening. Fertilized eggs are traveling to the uterus and implanting, and tiny gestational chambers become visible on ultrasound as early as day 10. But outwardly, your cat will look and act like her normal self. Some cats show a subtle increase in appetite during this window, though it’s easy to miss or chalk up to normal variation.
Week 3: The First Visible Sign
The first change you can actually see with your own eyes is the nipples. Around the third week, a pregnant cat’s nipples become noticeably larger and take on a deeper pink color. This is sometimes the only sign at this stage, but it’s a reliable one, especially in cats with lighter fur where the color change is easier to spot. If your cat’s nipples have always been pale and flat and they suddenly look rosy and puffy, pregnancy is a strong possibility.
This is also the earliest point when a veterinarian can sometimes feel the developing kittens through the abdomen. Gentle palpation is possible as early as day 15, but the sweet spot for accuracy is days 21 to 25, when the individual uterine swellings are still distinct enough to count.
Week 4: Morning Sickness and Appetite Shifts
Around four weeks in, some cats experience morning sickness. Just like in humans, this can include vomiting and going off food, and it’s not limited to the morning. Your cat may seem uninterested in meals she’d normally devour or eat a few bites and walk away. Not every cat goes through this, but it’s common enough to be a recognized sign.
A hormone called relaxin, produced by the developing placenta, rises sharply around days 20 to 25. By day 29, a vet can use a blood test for this hormone to confirm pregnancy with high reliability. If you want a definitive answer before the belly starts growing, this is one of the most straightforward options.
How a Vet Confirms Pregnancy
There are three main ways a veterinarian can confirm that your cat is pregnant, each useful at different stages.
- Abdominal palpation works best between days 21 and 25. After day 35, the uterine swellings merge together and individual kittens become harder to distinguish by touch alone.
- Ultrasound can confirm pregnancy around days 22 to 25. It picks up fetal heartbeats as early as days 16 to 17, making it a good option for early detection, though not every clinic has ultrasound equipment on hand.
- X-rays become useful much later. Fetal skeletons don’t mineralize enough to show up on a radiograph until roughly 36 to 40 days into the pregnancy. X-rays are most helpful in the final weeks for counting how many kittens to expect during delivery.
Weeks 4 Through 6: Behavioral Changes
As pregnancy progresses through the middle weeks, many cats become noticeably more affectionate. Your cat may follow you around more than usual, seek out lap time, purr more readily, or want to sleep pressed against you. Some cats become almost clingy, staying close during activities where they’d normally wander off. Others go the opposite direction and become more withdrawn, spending more time hiding or avoiding contact. Both reactions are normal responses to the hormonal and physical changes happening in their bodies.
You may also notice your cat becoming more protective of her space. She might seem more alert to sounds and movements in the house, or react more strongly to unfamiliar visitors. This heightened vigilance tends to increase as the pregnancy advances.
Weeks 5 Through 7: The Belly Grows
Visible abdominal enlargement typically becomes obvious in the mid to late stages of pregnancy, roughly from the fifth week onward. This is the point when most owners who didn’t know their cat was pregnant start to notice something is different. The belly rounds out gradually, and your cat gains weight overall, not just in the abdomen.
Her appetite will likely swing back up after the earlier dip from morning sickness. In the last trimester, spanning roughly days 42 through 63, many cats become voracious eaters. This makes sense because the kittens are growing rapidly and need calories. By at least the end of the first month, it’s a good idea to switch a pregnant cat to a high-calorie food labeled for kittens or for pregnancy and lactation. That same food should continue through nursing until the kittens are weaned.
As the kittens take up more room inside, your cat’s stomach capacity shrinks. She may start eating smaller meals more frequently rather than finishing a full bowl in one sitting. Leaving food available throughout the day can help her get enough calories without discomfort.
Weeks 7 Through 9: Preparing for Birth
In the final stretch of pregnancy, physical changes become hard to miss. The nipples and mammary tissue enlarge further, and your cat may begin licking her belly and vulva more frequently. You might be able to see or feel the kittens moving inside her abdomen during the last week or two.
During the final week, most cats begin nesting. This means actively searching for a quiet, enclosed, comfortable spot to give birth. She may explore closets, burrows under blankets, or try to squeeze into small spaces she’s never shown interest in before. If you provide a box lined with soft towels in a quiet area of the house, she may adopt it as her chosen spot.
The vast majority of cats deliver between days 61 and 70, with the average right around day 65. The full range runs from 57 to 72 days, so there’s some natural variation. If your cat reaches day 70 without going into labor, or if she seems distressed, restless, or straining without producing kittens, that’s a situation that calls for veterinary attention.
Quick Timeline at a Glance
- Days 1–14: No visible signs in most cats
- Days 15–21: Nipples pinken and enlarge
- Days 21–25: Vet can confirm by palpation or ultrasound
- Day 28–29: Blood test for relaxin becomes reliable
- Day 28: Morning sickness may appear briefly
- Days 35–45: Belly visibly enlarges, appetite increases
- Days 36–40: Fetal skeletons visible on X-ray
- Days 58–65: Nesting behavior, frequent grooming, visible fetal movement
- Days 61–70: Delivery for 95 to 97 percent of cats