The scene outraged bystanders, who repeatedly attempted to contact emergency services.
Erika Service, who witnessed the event in Prince Albert Rd, said she called for an ambulance about 11.05am and one had still not arrived almost an hour later.
Firefighters were first on the scene almost 45 minutes after the woman’s medical episode.
"She came out of the laundromat and she was looking a bit funny," Ms Service said.
"I asked her if she was OK, and then she said no and then she fell and I kind of caught her.
"We stopped her from hitting her head on the ground."
The woman was very unwell and she believed she had stopped breathing at one point, she said.
After alerting St John, she was called back by an operator and told no ambulances were available.
"It’s upsetting," Ms Service said.
"This is going to cost lives."
The woman was attended to by a nurse from Aurora Health Centre and firefighters from Willowbank, before paramedics arrived at the scene about noon.
St John said it was unable to comment on individual cases, but resources were placed under stress yesterday because of a high number of calls.
"As soon as St John noticed a spike in demand for its services this morning, it called in extra resources, including four extra ambulances and additional staff," St John coastal Otago territory manager Doug Third said yesterday.
The demand on resources at this time of year was not unique to St John and other health services in the region had also experienced increased demand during winter, he said.
"St John advise the public to visit your local GP for non-urgent health concerns, call Healthline on 0800 611-116 for free advice from a nurse and for emergencies please continue to dial 111."
