Gestation period for the cats is normally 63 days. Then your cat will be in labor for around 18 to 24 hours. Cat labor has 3 stages. The fist stage lasts for 6 to 12 hours, when the cat starts showing the sign of pain. Its placenta get dilated in this stage. Then the 2nd labor stage starts, with the beginning of contraction. The cat delivers its first kitten within 1 to 2hours. Then there might be a resting period with a duration of 30 minutes to 4 hours, and other kittens are also delivered after that.
The third stage of labor consists of removal of placenta. It begins 10 to 15 minutes after birth.