"This is a tragic and extremely difficult situation and I extend my sympathy to all those involved,'' said Southern DHB chief executive Carole Heatly.
"We are conducting a thorough review of the care Mrs Milton received. We are committed to ensuring all out patients receive safe, high-quality care, and if that was not the case, we will undertake clear action to improve our service.''
Mrs Heatly said the DHB was limited it what it could say about the case because it needed to respect patient privacy and the police investigation into the girl's injuries was ongoing.
Police have said the baby's parents, David and Sucharitta Milton, were at home at the time of the incident about 5.30am on Monday.
The parents had been spoken to and police were not looking for anyone else.
Several neighbours reported hearing noises from the property early on Monday before emergency services were called to the Princes St home.
