Pictures of smiling babies crowd a bulletin board in a doctor’s office in Midtown Manhattan, in a collage familiar to anyone who has given birth. But the women coming in to have babies of their own cannot see them. They have been moved to a private part of the office, replaced in the corridors with abstract art.

“I’ve had patients ask me, ‘Where’s your baby board?’ ” said Dr. Mark V. Sauer, the director of the office, which is affiliated with Columbia University Medical Center. “We just tell them the truth, which is that we no longer post them because of concerns over privacy.”

For generations, obstetricians and midwives across America have proudly posted photographs of the babies they have delivered on their office walls. But this pre-digital form of social media is gradually going the way of cigars in the waiting room, because of the federal patient privacy law known as Hipaa.

Under the law, the Health Insurance Portability and Accountability Act, baby photos are a type of protected health information, no less than a medical chart, birth date or Social Security number, according to the Department of Health and Human Services. Even if a parent sends in the photo, it is considered private unless the parent also sends written authorization for its posting, which almost no one does.