Above are the first set of triplets known to have been born in captivity. While polar bears often give birth to more than one cub at a time, triplets are relatively rare compared to twins. Furthermore, the runt of the litter is often edged out by its bigger, stronger siblings. If unable to successfully compete for the mother's milk, it will die of starvation.
Even in zoos, where food and care are plentiful, nearly half of the polar cubs born in captivity die. But Ouwehands Zoo officials seem to have luck on their side: All three cubs are healthy and are expected to survive into adulthood.Link. At least they are playing with each other, and not associating with foreign species.