How do I know if my Maine Coon is pregnant?

Maine Coon cat vet with an ultrasound machine that can detect pregnancy. Image: MikeB

Ultrasound may detect pregnancy at day 15 and there is a cat and dog pregnancy test available for day 30. In between, at day 20 a vet will feel for the tiny embryos (palpate). 

The pregnancy test is called FASTest® RELAXIN. It is a "rapid immunochromatographic assay for the qualitative detection of the pregnancy hormone relaxin in plasma or serum of the dog and cat". 

It is the only known pregnancy-specific hormone of the carnivores (dog and cat) that informs about the presence of relaxin producing placenta tissue. Therefore, it is perfectly suitable for an indirect proof of pregnancy in the female dog.

I have never used it to check if my cat is pregnant because I don't breed cats. I don't have any knowledge about its efficacy and safety. It seems that you can buy it online but I'd see a vet about this. It is too important. 

Maine Coon cat at vet with an ultrasound scanner. Image: DALLE E. This is an artificially created image using artificial intelligence.

As I understand it, the weakness of this test is that it can detect pregnancy after about 30 days which is almost half way into gestation at 65 days. There will be other signs by then. The nipples will be pink and obvious and the size of the belly will have increased.

Below I mention how an experienced evaluator can detect pregnancy at day 15 using ultrasound.

Signs of pregnancy in a domestic cat including the Maine Coon

The video starts at a point where the signs of pregnancy are discussed.

Historically - determining pregnancy

At the time that my reference book on veterinary care was published, 2008, there was no early pregnancy detection test available for cats the way there is for people. That appears still to be the case because the above-mentioned hormone test is not an early test.

And therefore, the veterinarian has to rely upon other means which don't help during the first few weeks of gestation as there are few early detectable signs of pregnancy except for a slight gain in weight.

A veterinarian might perform an abdominal ultrasound. My reference book tells me that an experienced evaluator may detect pregnancy as early as day 15. 

Thereafter, fetal heartbeats are detectable at day 20 which provide an absolute indication of life and therefore pregnancy.

Also, at day 20, the growing embryos can be felt by abdominal palpation. They feel as evenly spaced swellings about the size of "unshelled peanuts".

Non-veterinarians are not advised to palpate their female cat to check for pregnancy in this way because it requires experience and gentleness and there are other structures in the abdomen that may feel lumpy. 

A cat owner cannot go around poking and prodding their female cat to check for pregnancy because it may damage the fetal-placenta units causing a miscarriage.

By day 35 the nipples are pink and it's clear she is pregnant plus the size of the belly has increased.

P.S.

It occurred to me that the question in the title must have been asked by a Maine Coon owner who is not a breeder. Without having any intent to lecture, it is not a good idea to informally breed cats. There are too many already. And too many in rescue centers.