Altricial is the adjective (the noun is "altriciality") applied to animals that are born, or hatched, in a vulnerable or undeveloped state.
An altricial animal is usually unable to move, or eat on its own, and often will also be blind or deaf at the time of birth. Altricial animals only can survive at all through intense parental energy, as they are defenseless and helpless from the time of birth. Despite being a seemingly risky evolutionary strategy, many altricial animals have been quite successful, including ants and bees, perching birds, most carnivorous animals, and of course, humans.