If a bitch falls pregnant she will show little or no outward changes for the first four weeks of pregnancy. Inside her, however, the most crucial stages of her pregnancy are taking place. About 10 days after the mating the fertilised eggs enter the uterus. After a further 10 days of growth and development the embryos attach themselves to the uterine wall.

By 5 weeks the puppies have finished developing their basic shape and their vital organs. They now begin a phase of rapid increase in their size. The uterus has become swollen and heavy.
In general the appetite of the bitch increases to meet the demands of the growing litter. She may show a change in behaviour - usually she’ll be quieter and slightly less active, but not always.
Her nipples may become swollen and pink at about 6 weeks. Milk does not usually appear until a few days before whelping, but in a maiden bitch may only be present after the arrival of the first whelp. In a bitch who has whelped before, it may appear as much as 2 weeks beforehand!

At about 28 days after the mating, a veterinarian can scan the abdomen of the bitch with ultrasound to determine if the bitch is in fact pregnant or not. This is by far the safest and easiest method of determining pregnancy, although palpation of the abdomen is still widely used as well.

An X-ray can only used after 7 weeks, but this exposes the bitch and whelps to possible harmful side-effects.In the first 4 weeks of pregnancy a bitch in good condition requires no extra food. After 4 weeks food can be increased gradually so that the bitch is getting about one third extra each day by 5 weeks and about 50% extra just before whelping. Any changes in diet must be gradual.
Do not allow the bitch to become too fat, this can result in problems during the actual whelping, just as being too thin can also be problematic. Watch the condition of the bitch. During the last 3 weeks of pregnancy, divide the daily portion into about 3 equal portions and make sure fresh water is readily available, as always.

The swollen uterus takes up much room in the abdomen and does not allow for much expansion of the stomache. For this reason, a bitch may not be able to control her bladder and other functions during pregnancy. Be prepared to either let her out a couple of times during the night, or put down papers and clean up after her in the morning. She cannot help this and should not be scolded! Often people feed extra vitamins and minerals during pregnancy. If you are feeding a balanced diet this may actually be harmful to the bitch.

Regular exercise is important during pregnancy to help sustain muscle tone for whelping and to help maintain general health and physical and mental well-being for the bitch. Strenuous exercise and rough games should be avoided.

During the last few weeks of pregnancy, a gentle walk twice a day is sufficient. Watch the bitch and her needs and do not over-do it!
Some bitches vomit during pregnancy, not because of "morning-sickness" as associated with humans, but rather because of pressure on the stomache by the swollen uterus. This can be prevented by giving smaller meals instead of one large daily meal. However, if it continues, and especially if associated with any form of diarrhea, consult a veterinarian immediately.
Use a product like Frontline to ensure no FLEAS are present.

Your bitch should have had her yearly inoculation and de-worming before the mating. Two weeks before the whelping, she should be de-wormed again to ensure no internal parasites are present. De-worm again about 10-14 days after the whelping.Take your bitch for a final check-up by your veterinarian about one week before whelping.

Make sure your vet knows the expected date of whelping and that he/she will be available for any problems which might occur. Make sure you know the emergency number of the attending vet, because often bitches choose the middle of the night to whelp and problems can occur. Discuss any possible problems with your vet beforehand so you will know what to do and when to call for help.