A Newmarket, Ont. woman pleaded guilty to aggravated assault on Monday after giving clients illegal buttock injections.

Police said Marilyn Reid, 48, advertised Botox injections and buttock, lip and muscle augmentations online and arranged to meet clients at their homes or in hotels.

She told her clients she was a certified plastic surgeon, but she wasn't registered in Canada.

According to her lawyer, Calvin Barry, she'd never been a doctor.

The women each paid approximately $5,000 cash and received several injections of polymethyl methacrylate, or PMMA, a type of plastic sometimes used by cosmetic surgeons. They were injected with PMMA using a caulking gun and a needle.

The website was brought to the attention of police when one of Reid's clients became ill. The 28-year-old, who has not been identified, had to be taken to hospital, where she underwent surgery to have the substance removed.

Many of the clients suffered similar infections, and will have health problems for the rest of their lives, the court heard.

During a police investigation, nine women accused Reid of botched Botox injections between April 2011 and June 2012. Police said she was paid thousands of dollars for the treatments during that time period.

Reid pleaded guilty to eight counts of aggravated assault Monday.

She is scheduled to reappear in court on Feb. 27. The Crown is asking for a prison sentence of eight or nine years.