* Complications during birth: Just like human babies, puppies can face challenges during birth. This could include being born in the wrong position, being too large to pass through the birth canal, or having problems with the placenta.
* Health problems: Puppies can be born with genetic health conditions, infections, or other health issues that can make it difficult for them to survive.
* Lack of care: Sometimes puppies die because they don't receive the care they need from their mother or from a veterinarian.
It's important to remember that while death is a natural part of life, it's always heartbreaking when it happens to a young animal. If you're concerned about a pregnant dog, it's important to take her to a veterinarian for prenatal care and monitoring.