Both newborn and older puppies might need assistance with bowel movements, either because they haven't developed bowel control or because they're constipated. Newborn puppies might eliminate every 30 to 45 minutes. Older pups should poop at least twice a day. If you catch the problem early, you can often remedy it through diet or other simple remedies.
Puppies can't defecate on their own until around 3 weeks of age, before which the mother stimulates elimination by licking around the anal area. If you're hand rearing young puppies, however, you might have to do it. You can do this by rubbing a cotton ball or towel moistened with warm water around the anus and genitals. The puppy should have a bowel movement within one to two minutes. Newborn puppies should be stimulated after every feeding.
If an older puppy becomes constipated, your veterinarian might recommend changing his diet, adding supplements or administering medication designed to encourage bowel movements. Vets often recommend increasing dietary fiber, perhaps by adding canned plain pumpkin or wheat bran to his food. If that doesn't work, you vet might suggest a stool softener or laxative. For hard-to-treat cases, your vet might want to administer an enema, something that should be performed only by a trained professional because of the risks involved.