If you're not planning to breed from your dog then it's best to have her spayed. If, however, you make the big decision to allow her to have puppies you're in for quite an adventure - here are a few signs that indicate pregnancy in dogs.

Your dog's teats will become swollen and more prominent 25 -30 days into the pregnancy. She also will start producing a vaginal discharge about one month after mating. You will usually notice her stomach swelling as she puts on weight 45-50 days after conception. Some dogs will also demonstrate a loss of appetite or signs of depression during gestation (pregnancy).

A trip the vet

If you think your dog is pregnant you need to take her to the vet. This is both to confirm the pregnancy and to catch any complications that may arise early.

Your veterinarian will use a number of different methods to determine if your dog is pregnant. After 21-25 days your veterinarian can perform a test for relaxin, a hormone produced only by pregnant dogs. This method will confirm pregnancy but not the number of pups.

By feeling your dog's abdomen after 21 days, your vet may detect a thickening of the uterus and the presence of 'bumps' which indicate pregnancy. However a number of things can interfere with this method: an overweight dog, a single puppy or even just nervousness can make it difficult to administer a proper 'feel'.

A stethoscope or ECG can detect puppy heartbeats after twenty-five days but will probably not be able to distinguish individual heartbeats making it a poor tool to determine how many puppies there are.

A common pregnancy assessment is with an ultrasound. This is non-invasive, reliable and can detect puppies at about 28 days.

The most accurate method of counting puppies is with an x-ray, which can detect skeletons after 49 days. Some vets will advise against performing an x-ray to avoid exposing the developing puppies to radiation.

Preparing for a new litter

In the months leading up to the birth there is not a lot you need to do for your expecting mother besides ensuring she continues to receive a good, healthy diet. You should encourage her to exercise so she's in good shape for what could be a long and drawn out birth.

In the days before your dog gives birth she'll probably start becoming restless and scratching at the ground or in her bed. She's looking to make a nest for the delivery. You should provide her with an enclosure, ideally this should be something she will be able to come and go from, but confine the puppies.