Maryland State Police are investigating the alleged rape of a 19-year-old deaf, mute and blind woman who was under "24-hour" care at two Maryland facilities for the handicapped when she was sexually assaulted four months ago, state health and police spokesmen said yesterday.

Officials of the Great Oaks Center, a state-licensed facility in Silver Spring for the mentally retarded, and the Maryland School for the Blind in Baltimore recently referred the woman's case to state police after she became visibly pregnant, said Cpl. Donald R. Chipley.

Chipley, noting the woman's handicaps could hamper the investigation, said police plan to interview several employes at both facilities who came in contact with the woman.

"We're trying to narrow down where she was at the time of impregnation," Chipley said. "But she can't communicate with us. She can't talk, can't hear. Where do you go from there?"

Chipley, one of two detectives investigating the assault, said police plan to interview about 10 employes at Great Oaks and an undetermined number of staff members at the Maryland School for the Blind. For the past several months, the woman has spent weekdays at the school in Baltimore and weekends in Silver Spring, according to Great Oaks deputy director Paul E. Joyce.

"We consider this an act of sexual abuse," Joyce said. "We wanted an external party to investigate it and we'll let the chips fall where they may. If we're guilty, we'll take corrective action."

Great Oaks Center, which straddles the border between Montgomery and Prince George's counties, is licensed by the state and has about 445 patients with a variety of handicaps and learning disabilities.

The Maryland School for the Blind has 222 students and receives about $5 million annually from the state. School Superintendent Richard L. Welsh declined to comment specifically on the woman's case but did say, "If there's any police investigation, we will cooperate."

No arrests have been made in the case, said Chipley, adding that police would first concentrate their investigation on the two schools because she received "full-time, 24-hour" care there.

Physicians at the Baltimore school performed the first test that indicated the woman was pregnant and doctors at Great Oaks later performed similar tests, Chipley said.

Last Friday, police received results of a sonogram that showed the fetus to be about four months old.