Hacienda HealthCare says investigators served a warrant Tuesday, asking for DNA samples from male employees.
Hacienda officials have called the situation "a deeply disturbing incident" and said they are cooperating with law enforcement and state agencies.
The woman has not been named but she's been described as a 29-year-old Native American woman who has been in a vegetative state for 14 years after almost drowning.
A police investigation is under way, while inspectors from Arizona's department of health services have checked on patients and implemented "heightened safety measures".
[Redacted], 29 years old, is a patient at the Hacienda Del Sol in Phoenix, and has been in a persistent vegetative state and coma for over a decade.
Hacienda HealthCare's chief executive, Bill Timmons, stepped down on Monday, spokesman David Leibowitz said. According to the local station's unidentified source, the facility staff had no idea the patient was pregnant until she began moaning as she went into labor.
"To that end, we are re-evaluating the state's contract and regulatory authority as it relates to this facility and have been working closely with state agencies to ensure all necessary safety measures are in place".
Hacienda board executive vice president Gary Orman said the facility "will accept nothing less than a full accounting of this absolutely horrifying situation".
The woman's family said through an attorney that she gave birth to a baby boy.
In one case, the Arizona Department of Health Services cited the company in 2017 for an incident in which a certified nursing assistant walked in on a male patient while he was showering.
State records show complaints about Hacienda de Los Angeles going back to 2013.
Majority involve fire drill and evacuation preparation or Medicaid eligibility. That employee was later fired.
In the statement, the lawyer, identified as John Michaels, said the family is "outraged, traumatized, and in shock by the abuse and neglect of their daughter at Hacienda Healthcare".
When asked about the warrant, a police spokesman said only that the investigation was ongoing. "But things like this don't happen without someone either knowing about it or should have known about it", Solomon said. The caregiver was also incensed at the facility's staff, who she says should have noticed her gaining weight or missing periods.
Advocates for the disabled say Arizona needs to find a way to monitor allegations of sexual abuse and sexual violence in group settings.
"We don't have a systematic way to train people what's a good touch or a bad touch". "We really need a lot of work in this area". "I myself have come in a back way many times with no one noticing me", the caregiver said. "I haven't been able to sleep well at night because of what occurred here", a mother, Angela Gomez, told CBS.