Gov. Robert F. McDonnell of Virginia (Washington Post file photo)

The new regulations, which abortion-rights groups have said could shut down many of the state’s clinics, took effect immediately.

McDonnell’s signature, which was expected, was the last hurdle for the stricter standards, which earlier cleared Virginia’s departments of Planning and Budget, and Health and Human Resources.

“These regulations are a product of an amendment that passed both the House and Senate with bipartisan support,” Taylor Thornley, McDonnell’s deputy communications director, said in a written statement. “The governor believes these common-sense regulations will help ensure that this procedure takes place in facilities that are modern, safe and well-regulated, in order to help ensure the safety and well-being of all patients.”

The regulations treat abortion clinics as ambulatory surgery centers instead of doctor’s offices, as they have been classified. Clinics must meet hospital-type standards mandating the size of exam rooms and the width of hallways. The regulations also establish new requirements for inspections, medical procedures and record-keeping.

Antiabortion advocates say the changes will make the clinics safer for women. Abortion-clinic operators have said the regulations, approved in September by the Virginia Board of Health, could cause many of the state’s clinics to close.