These high-priced medications are often shifted to the top tiers of drug plans, so consumers dealing with cancer, multiple sclerosis, HIV and other complicated diseases can end up paying thousands of dollars for their prescriptions.

The health law called for all FDA-approved birth control methods to be completely covered by insurance, but research suggests that many women still pay for some of the costs for options such as IUDs and injectable contraceptives.

In North Carolina and elsewhere, hidden costs have popped up on “fully covered” services ranging from contraception to cancer screening to annual checkups, and it’s leaving a growing number of people to cover thousands of dollars out of pocket.

Under a new state law, Massachusetts insurers have to post how much tests and procedures cost at different providers in a consumer-friendly way.