Probably because there’s a lot more white doctors than black doctors, so most black infants will be “looked after” by a white doctor. Also, many black infants are very low birthweight or born with other problems and need specialists, and probably there are virtually no black neonatalists.
Don’t forget the popular “crack babies”.
In the hospital I work at in southern NJ I’d say about 98% of the doctor’s are all East Indian and Pakistani.