Senior doctors fear someone could be killed or seriously injured if the problem isn't resolved soon.
"When we think about who is affected by harmful alcohol or drug use, we don't usually think of Asian New Zealanders."
The Health and Disability Commission found Te Whatu Ora Southern breached the Code which gives consumers the right to services provided with reasonable care and skill.
The overloaded Women's Health Service is now only taking on the most urgent of cases.
The woman had a long-standing allergy to penicillin and was still prescribed antibiotics.
Violent incidents against staff in healthcare settings have risen across all Te Whatu Ora settings.
"It's at times a very difficult, dangerous place to work and it can be a very difficult, dangerous place to be a patient."
The care provided did not support the woman in adequately managing her diabetes throughout her pregnancy and resulted in the woman miscarrying at eight months.