Toronto police say they were called to a hospital on Thursday, where a woman claimed she had given birth but didn't know where her child was.
Homicide investigators were soon called in.
Insp. Greg McLane, head of Toronto's homicide squad, told CBC News that investigators spoke with medical staff and the woman, concluding that she had indeed given birth.
The baby has not been located, though police allege the woman killed the child.
"The information that we're following up on is that the child was discarded into a clothing bin," said McLane.
Homicide investigators in British Columbia confirmed Monday night that the search for the infant's body had shifted to the province's Lower Mainland.
The woman had been living with her family at a home in the area of Victoria Park Avenue and O'Connor Drive in Toronto. Forensic investigators continued to search the home on Monday.
Neighbours said the woman's parents were not aware that she was pregnant.
Angelica Spanidis, 25, faces a charge of first-degree murder. She appeared in a Toronto court on Monday.