When it comes to providing good health to an expecting feline, there are some important guidelines that you should consider.

Care of a Pregnant Cat – Cat Reproduction 101: Lesson 5
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Pregnant Cats Need Calcium
Pregnancy (and subsequent nursing) causes a depletion in the amount of calcium in the bloodstream. This condition can result in eclampsia, a life-threatening disease. Although it more often occurs during nursing, it can occur during the last stages of pregnancy. A calcium supplement can help prevent this potential problem, particularly when caring for a pregnant stray cat.

In addition to quality food, make sure that fresh, clean water is available at all times. The best way to provide this essential is with an automatic water fountain.

Routine Care for a Pregnant Cat
Other than kitten food and KMR during the last trimester, for the most part, a pregnant cat needs the same good care you would give any other cat:

A Comfortable Place to Sleep
This can be anywhere from sharing your bed, to a cardboard box lined with a fluffy towel or blanket, to a comfortable commercial bed designed for cats.

A Litter Box and Quality Litter
As your pregnant cat’s abdomen begins to enlarge, make sure her litter box is low enough for easier ingress and egress. Keep the box scrupulously clean to avoid possible infections from soiled litter. Refresh your knowledge of litter box cleaning techniques with this article on Litter Box Maintenance.

Scratching Post,Cat Toys, and a Cat Tree
Pregnant cats are just like other cats, in that they need the stretching activities they can get from a nice long scratching session, an interactive play session (take care not to tire her), and a nice spot from which to relax and view the world below.

Keep Your Pregnant Cat Indoors
This should go without saying, but if your cat became pregnant because of unlimited outdoor privileges, you really should train yourself and her to keep her inside. This is extremely important for her safety and your peace of mind.

Read More: http://cats.about.com/od/reproduction/a/pregnant_care.htm

Remember after the mother has delivered her kittens, she will spend the first few weeks with them feeding, cleaning and regulating their body temperature by keeping them warm. Make sure you’re providing a quiet area for her and the kittens away from other pets and high traffic areas of the home. Take the mother and kittens to your vet to have a check-up within the first month to be sure she is maintaining good health as well as her kittens to insure they live a long and healthy life.