The Obama administration says health insurance plans must cover birth control for women with no copays.

The requirement, affecting most insurance plans, is part of a broad expansion of women's preventive coverage. Breast pumps for nursing mothers, an annual "well woman" physical, counseling on how to avoid sexually transmitted diseases and other services will also be covered at no cost to the patient.

The new benefits won't take effect for at least another year, Jan. 1, 2013, in most cases. Insurers are expected to pass the cost on to their customers through slightly higher premiums.

The rules issued Monday by Health and Human Services Secretary Kathleen Sebelius include a provision that would allow religious institutions to opt out of offering birth control coverage.