Auckland Council's acting head of active recreation Garth Dawson said a woman got into trouble in the water and was pulled from the pool by a lifeguard.
"The woman took in some water, but was conscious and breathing once she was out of the pool and was able to communicate with staff," he said.
"However, due to a pre-existing medical condition she was taken to hospital as a precaution.
"Our thoughts are with the woman and her family and we wish her a full recovery."
The Mt Albert Aquatic Centre is owned by Auckland Council and managed by Belgravia Leisure.