Dozens of women were filmed without their knowledge while receiving medical attention — including having surgery and giving birth — at a California hospital, according to a lawsuit filed last week in a state superior court. A lawyer for the women said 1,800 patients may have been filmed.

The lawsuit alleges that motion-activated cameras were set up in three operating rooms at Sharp Grossmont Hospital in La Mesa, Calif., as part of an effort to catch a possible medicine thief.

But between July 2012 and June 2013, the cameras also recorded female patients at the hospital’s Women’s Health Center as they consulted with physicians, got undressed, underwent examinations and went under anesthesia for operations, according to the complaint.

Eighty-one women are named as plaintiffs and more are expected to join, said the lawyer, Allison H. Goddard. She said that the videos did not appear to include audio, but that some women’s faces were visible.