Q: My dog was diagnosed with heartworms while she was pregnant and delivered a month later. Can puppies get heartworms from their mother? A: That is a great question. Fortunately, the answer is no, the puppies cannot get heartworm from their mother. The ONLY way for the puppies, or for any dog, to get heartworm is to be bitten by a mosquito that is carrying heartworm. The puppies can, however, get intestinal parasites from the mother if she has any. Be sure to have your veterinarian check stool samples so that they can treat any parasites that may be present. The mother will have to be treated for her heartworm disease but your veterinarian will most likely do so once the puppies have been weaned. It is very important to use a monthly heartworm preventative in all dogs that live in warm environments or anywhere that mosquitoes exist. Where there are mosquitoes, there is heartworm disease! Even indoor only dogs are at risk since mosquitoes can enter the home. Heartworm prevention is only available as a prescription from your veterinarian who will likely perform a heartworm test before starting the medication.