About 65 days. A variation of four days either way is not unusual, so the whole cat gestation period may be as short as 61 days or as long as 69.
the first distinct signs of pregnancy happen around two or three weeks after mating. If pregnant, your cat's nipples will start to "pink up" and enlarge a bit in preparation for milk. Then, at between three and four weeks of pregnancy, she may get morning sickness and vomit from time to time. From four weeks onward, the kittens will be visible on an x-ray or sonogram, and may be able to be counted.
Finally, at five weeks your cat's abdomen will start to enlarge. At roughly seven weeks, the queen may begin to lose her appetite and refuse to eat. At this point, the kittens' movement can easily be felt. At seven to eight weeks, she will spend a lot more time grooming herself and might look for a place to have her kittens. Her nipples will then also become even more swollen. They might even expel milky fluid between two to five days before birth. As your queen nears her time for giving birth, she will exhibit a few signs that will give you clues to the impending arrival of kittens. The first stage of labor lasts from 12 to 24 hours, and may include the following "symptoms."
Nesting. She may start snooping around in closets and secluded areas for an appropriate place to bear her kittens. The time is ripe for you to prepare an area for her in a private place, with a box or basket lined with soft towels. She may decide instead to give birth on the cold, hard floor of your bathroom, but at least you have tried to accomodate her needs.
Increased affection. She may suddenly become very loving, and want to be near you at all times. Don't be surprised though, if a previously affectionate cat becomes withdrawn and seeks solitude. Either personality change may be completely normal.
Decreased Activity. Queenie may decide she'd rather sleep most of the time. She may also lose interest in food.
Milk Discharge from Nipples. Your cat's nipples will have become enlarged and pink about the third week of pregnancy; 24 hours or so before birth, she may show a milky discharge. This discharge may come even earlier in cats that have given birth several times.
Drop in Temperature. The normal temperature in cats is between 100.4°F and 102.5° F. A dramatic drop in her rectal temperature is a sure indicator that birth is imminent
Contractions will start and you will see the appearance of the amniotic sac. You may also see a discharge of blood or other colored fluid. The first stage of labor lasts from 12 to 24 hours.
In general, it may take up to six hours for a queen to give birth to all her kittens. The first kitten should arrive within an hour of the start of active labor, and subsequent kittens will take anywhere from 30 to 60 minutes. She will rest for 15 minutes or so between kittens, and during this time she should be allowed to nurse and clean the kittens that have been born, Although in rare cases a healthy kitten is born after the seven hour period, you should take the queen and her kittens to the vet for a checkup once seven hours passes and you are sure there are other kittens inside.
Extended Contractions without Birth
More than one hour of strong contractions indicates a veterinary emergency, and your cat should be seen by a vet immediately. Take her and any kittens to your vet.
A retained placenta can cause uterine infection. It is important to count the number of placentas (one per kitten) to keep on top of this potential problem.
Kitten Lodged in the Birth Canal
A kitten that is lodged in the birth canal for more than 10 minutes is in distress, and your intervention may be necessary. Note that although most kittens are born head first, "breech," or tail-first births occur about 40% of the time, and are considered normal.