Women are saving significant money on birth control under contraception coverage requirements in the Patient Protection and Affordable Care Act.

A new study published in the journal “Health Affairs” estimates the savings at $1.4 billion annually:

• Out-of-pocket spending on birth-control pills fell from $245 to $117 in a six-month period, for an annual savings of $255 for each of seven million users.

• Users of intrauterine devices each saved $248 annually.

Although PPACA generally requires contraception to be free to the patient, that requirement does not apply to every form of birth control. Other studies show that some insurance companies are not following the requirement in every respect, which helps explain why out-of-pocket spending has fallen but is not at zero. 

The Obama administration in May told insurers that they have to cover at least one version of each of 18 federally approved birth control methods. 

Read: Are insurers skirting PPACA’s birth control rules?

Sen. Patty Murray (D.-Wash.) introduced a bill to ensure that insurance companies still cover birth control at no cost to the patient, even if it is being purchased over the counter.

“It’s great news that as a result of progress made in the Affordable Care Act, women across the country have more affordable access to critical health care like birth control," she said. "This is good for women, it’s good for our country and it’s progress we need to continue to build on going forward.”

The contraception mandate has been controversial, drawing lawsuits from religious groups concerned that they are being forced to violate their beliefs.

Sen. Cory Gardner (R.-Colo.) has led a group of Senate Republicans in proposing a bill that encourages birth control to be sold over the counter, as he promised in last year's Senate campaign. His proposal has drawn criticism from Democrats, who have warned that being able to buy birth control without a prescription is little help if it is too expensive.