BOSTON — With the future of Obamacare endangered under President-elect Donald Trump and a GOP-controlled Congress, women’s rights groups want to preserve a popular provision of the health care law requiring insurers to cover birth control.

The federal Affordable Care Act requires insurance companies to cover all methods of birth control approved by the Food and Drug Administration, with no co-payment or co-insurance when provided in-network. The state’s health care law, which went into effect in 2006, doesn’t include such a provision.

Advocates want lawmakers and Gov. Charlie Baker to add the mandate, but the proposal will likely face opposition from insurers and state officials wary of driving up costs.

A similar bill introduced in the current legislative session failed to win support. State Senate Majority Leader Harriette Chandler, D-Worcester, its primary sponsor, said she plans to revive the bill next year.

“This issue will be critical for the Legislature next session, given that the president-elect has made clear his intention to repeal the ACA,” Chandler said in a statement.

Push to keep coverage

The Planned Parenthood League of Massachusetts and other advocates say they’ll push to extend the benefit to state law.

“Regardless of what happens to the Affordable Care Act, we need to make sure that Massachusetts law guarantees coverage, without cost sharing, for all types of FDA-approved contraceptive drugs, devices and supplies,” said Tricia Wajda, a spokeswoman for Planned Parenthood. “We need to prepare for the uncertainty.”

Wajda said earlier attempts to close gaps between Obamacare and state law focused on cases where birth control access was restricted, such as insurers who covered only certain kinds of birth control or required women to make co-payments.

With Obamacare facing repeal, the proposal has taken on added urgency, supporters say.

“If provisions of the (Affordable Care Act) regarding birth control go away, it’s going to be absolutely critical to replace it with a state law that protects Massachusetts residents,” said state Sen. Jamie Eldridge, D-Acton, one of the bill’s sponsors. “We’re a pro-choice state that supports birth control.”

Rising health care costs could complicate those efforts.

Massachusetts has some of the highest health care costs in the country, and state officials have wrestled with ways to reduce them.

Last year the state’s overall health care costs increased 3.9 percent to about $57 billion — above a state-imposed benchmark of 3.6 percent, according to state data. In 2014, health care spending went up by 4.8 percent.

Coverage costs

Health care costs were fodder in the fall presidential campaign, especially when federal officials announced that premiums for mid-level plans under Obamacare would jump an average of 25 percent.

A study by the state’s Center for Health Information and Analysis last year determined that requiring plans to include birth control coverage under state law would increase monthly health premiums by an average of 15 to 30 cents.

Eldridge, co-chairman of the Legislature’s Finance Committee, called that analysis “flawed.” He said the cost of unwanted pregnancies, sexually transmitted diseases and other issues that could stem from a loss of contraception coverage would be far greater.

Elizabeth Murphy, director of regulatory affairs for the Massachusetts Association of Health Plans, said Chandler’s proposal would “mandate coverage of contraceptive drugs for reasons other than contraceptive purposes,” which would increase premiums.

“Regardless of whether the ACA’s contraceptive coverage mandate is repealed, women in this state will continue to benefit from generous access to a broad variety of measures to prevent pregnancy for a modest co-payment through the state’s health plans and pursuant to state law,” Murphy said in a statement.

But Christian Miron, deputy director of NARAL Pro-Choice Massachusetts, said scrapping the birth control mandate will have a larger effect on low-income women.

Adding free birth control to the state’s health care law, he said, will be a “main priority” for the group next year.

“We want Massachusetts to send a clear statement to the country that we won’t allow Donald Trump to roll back reproductive rights for women,” he said.

Recent studies show the federal birth control mandate, in place since 2013, has increased usage of contraception and reduced costs, particularly for long-acting methods such as intrauterine devices.

Pence target

While Trump made a campaign theme of replacing Obamacare, he’s offered few specifics about how he will do that.

Since winning the presidency on Nov. 8, he has said he might keep provisions barring insurers from refusing to cover pre-existing conditions and forcing them to cover subscribers’ adult children up to age 26.

Trump hasn’t specifically targeted the birth control mandate, but Vice President-elect Mike Pence, a conservative Republican governor from Indiana with a long anti-abortion record, indicated during the campaign that he wants to eliminate the provision.

House Speaker Paul Ryan, one of the primary opponents of Obamacare, has refused to say whether Congress will keep the birth control mandate when overhauling the law.

Instead of taking a vote to scrap Obamacare, changes could come through provisions aimed at reducing government expenses. Trump could also change policies that define birth control as non-preventative care, eliminating the mandate.

Meanwhile, Wajda said Trump’s victory has prompted a surge in the numbers of women seeking birth control.

“People are worried about their access to health care under a Trump administration, and that includes birth control,” she said.

Christian M. Wade covers the Massachusetts Statehouse for North of Boston Media Group’s newspapers and websites. Email him at cwade@cnhi.com.