An advertisement in a CVS drugstore on busy Melrose Avenue in Los Angeles trumpeted the new service: “CVS pharmacists can now write birth control prescriptions.”

California law authorizes pharmacists to furnish hormonal pills, patches, and rings without a doctor’s prescription. Signed by Gov. Jerry Brown (D) in 2013, the law promised to make it easier to get birth control in a state where half of pregnancies are unplanned. In reality, the benefit can hinge on a patient’s insurance and ability to pay.

Major drugstore chains have rolled out the service in nearly 500 locations across the state. For a charge of $45, pharmacists at 378 Albertsons company drugstores can prescribe birth control to people with private insurance, government insurance, or no insurance at all who meet certain criteria, a spokeswoman told Rewire. The $45 fee pays for the “visit,” not the birth control, which is generally covered under the Affordable Care Act with no co-pay.

It’s a different story at CVS stores. The fine print on an ad noted, “Medicaid, Medicare and other government program beneficiaries not eligible.” The out-of-pocket charge is $29.

The CVS policy isn’t unique. Rite Aid has rolled out the service in about 20 of its 576 California locations. A Rite Aid pharmacist in Costa Mesa said he cannot write contraceptive prescriptions to those on government health plans. For others, the fee is $45.

A spokeswoman for CVS, which is piloting the service at 89 of its more than 1,100 CVS Pharmacy locations in California, cited “current Medicaid contractual regulations” as the reason people with Medicaid, the health plan for those with low incomes, are ineligible.

More than 2.3 million women of reproductive age are on Medi-Cal, as the state Medicaid program is known.

“So what happens is low-income women get shut out,” said Kathleen Besinque, professor of pharmacy at Chapman University, who helped write the California law. “Women who have the money will do it, women who don’t, can’t.”

Supporters of the state law considered it a natural complement to contraception without co-pay. While the law doesn’t make birth control available over the counter, it does bypass doctors, opening a new avenue to access contraceptives. Pharmacies are open longer hours than a doctor’s office, are able to accommodate walk-in patients, and are located in rural areas where a primary care doctor or gynecologist might be hard to find.

Washington state, Colorado, Oregon, and New Mexico have enacted similar laws. A sample of 195 women in a study in Washington state were happy with the benefit.

But what was intended as a boon to reproductive access has instead been stalled, as the state, drugstores, and insurers grapple with implementing the law.

Jon Roth, CEO of the California Pharmacists Association, described it as “sort of blazing the trail as we go.”

“It’s not like turning on a light switch where everything turns on in one day,” Roth told Rewire. “Birth control is being dispensed, it’s available, but it’s on a cash basis, and we still need to get the coverage of the patient under the health plans finished.”

Rite Aid spokesperson Ashley Flower, when asked about the reason the pharmacy charges a fee and bars those on government health plans, told Rewire, “That’s really up to the insurers and state government to decide and you’d be best to speak to them.”

It wasn’t until last fall that the state legislature passed a separate law to extend the program to Medi-Cal patients. The law requires the state to pay pharmacists for their time when they prescribe contraceptives. Besinque, the pharmacy professor, said the state “hasn’t started doing what the law says they have to do.”

Pharmacists say the the service they provide is like an office visit. They need to recoup the costs of delivering the care the state mandates, such as reviewing a patient health questionnaire, taking blood pressure, and providing contraceptive counseling. The out-of-pocket fee, they note, is an annual one.

If insurance won’t reimburse pharmacists for their time, they must pass the cost to patients, explained Virginia Herold, executive officer of the California State Board of Pharmacy, which regulates compliance with the law and public safety.

“Pharmacists are in business to make money,” Herold told Rewire. “When they don’t get reimbursed, it makes it hard for them to provide the service.”

Meanwhile, extending the program to California’s millions of Medi-Cal enrollees might face a significant hurdle: the Trump administration, which is staffed by anti-choice activists determined to interfere in birth control access.

Katharine Weir, spokesperson for the California Department of Health Services, told Rewire that the state may need federal approval to reimburse pharmacists who furnish birth control to Medi-Cal patients.

The earliest the service could be available is next summer, Weir said.