The legislators who drafted Obamacare wrestled with cosmic issues of health and spending, but here’s one consequence they didn’t foresee: a boom in demand for breast pumps that has left some retailers scrambling to keep up.

Tucked within the Affordable Care Act is a provision requiring insurance companies to cover breast pumps and visits to lactation consultants at no cost to the patient.

Other mandated benefits, including the requirement to pay for contraceptives, drew far more attention and controversy. But when health insurance plans began resetting Jan. 1 under the new terms, it was the breast- pump clause that took off with consumers.

“We’re getting a lot of calls from prospective mothers and new mothers,” said Bruce Frishman, president of New Hampshire Pharmacy and Medical Equipment, a  supplier based in the District. “We’ve started stocking a lot more pumps that would be purchased through insurance.”

Yummy Mummy, a New York boutique that specializes in breast pumps and accessories, is in the process of acquiring a warehouse and call center to accommodate the increased demand.

“I have three employees taking calls right now,” owner Amanda Cole said. “We’re still in the stage where we’re figuring out how to add fax machines and phone lines. It’s all very new to us.”

Specialty suppliers like Yummy Mummy stand to benefit from the change if they manage to get on insurers’ lists of approved distributors. Women who might have bought a  breast pump at a local retailer are now likely to turn to their insurance plan.

Cole opened her store in 2009 but never thought about working with an insurance company until last year, when she learned of the health law’s new requirement. She began to worry that if women got their breast pumps through their insurer, her store would not have any business left.

“I began pounding the pavement to get onto their list of providers,” said Cole, who recently signed a contract with Aetna to provide pumps nationwide. “Now that the plan really took effect on January 1st, there’s been a marked change.”

Insurance companies are figuring out the best way to navigate the federal regulation and provide a benefit that, until now, they had not routinely covered.

The government does not bear the costs of providing breast pumps. Instead, insurers will have to pay for the new benefit, likely with a slight increase to the premiums they charge their members.

Administrators of insurance plans still have questions about how to best implement the rule. No state has ever required insurance companies to cover the benefit, although Louisiana did convene a study panel on the issue in 2002, according to the National Center for State Legislatures.

“This was a medical service that is advantageous for both women and babies, so we thought it should be seriously considered,” said Judy Waxman, vice president for health and reproductive rights at the National Women’s Law Center, who testified on the subject before the federal panel that set the guidelines.

“Turns out,” she said, “that they decided to seriously consider it.”

Thirty-one states already require Medicaid, for the low-income, to cover breast pumps.

The health-care law’s requirement does not specify whether insurance companies must cover certain brands or types of breast pumps. It directs health plans to pay for “the costs of renting breastfeeding equipment” in conjunction with each birth. The breast pumps available for rental tend to be larger and more durable than those sold commercially, which are not intended for long-term use.

“There are various interpretations from the insurers,” said Rachel Mennell, a spokeswoman for Medela, one of the country’s largest makers of breast-feeding equipment. “There appear to be more questions than answers from not only the insurers, but moms as well.”

UnitedHealthcare, the country’s largest health insurer, decided it would cover rentals and purchases. Before the Affordable Care Act, the company had a patchwork of breast pump coverage, with some plans covering the equipment.

“The law states that we must provide rental pumps,” said UnitedHealthcare spokesman Matthew Stearns. “These pumps are hospital-grade, and they are larger, harder to clean and more expensive than personalized pumps for women. We are providing women the option of getting a personal pump in lieu of renting the more-expensive pump.”

Blue Shield of California will cover only equipment rentals. Before the Affordable Care Act, the company assessed requests on a case-by-case basis,  approving only those claims for the situations in which they were deemed medically necessary.

Health-insurance companies have also begun recruiting lactation consultants to join their networks so they can comply with the mandate to cover lactation support and counseling.

In late July, Aetna sent lactation consultants a letter noting that the company was expanding its “network of international board certified lactation consultants” and inviting providers to join.

Some lactation consultants, however, have declined these entreaties, saying that the reimbursement rates insurance companies have offered are significantly lower than  the amount they charge for a consultation.

“We as a company have decided not to sign up as a preferred provider,” said Diana West, of Mahala Mom, a lactation consulting company in Northwest New Jersey.

West’s consultations, which tend to run between 90 minutes and two hours, cost about $200 depending on the location. Insurance companies have made reimbursement offers that hover around $80, she said.

“This is a very big obstacle that my industry is really abuzz about,” she added.

Consumers, too, are still trying to figure out how to take advantage of the new requirement. Leila Abolfazli is a senior counsel at the National Women’s Law Center, one of the groups that advocated for the coverage. She gave birth in October and, as she prepared to return to work from maternity leave, called her insurance carrier in December to ask about obtaining a breast pump.

“They said they do cover it with no co-payment but I had to go through a medical supplier,” she said.

Two calls to the recommended medical suppliers were dead ends: One did not have the breast pumps, the other said it had not yet signed a contract with the insurer for the  coverage.

"Our plans started covering this back in August, and I’ve gotten birth control without a co-payment with no problem,” Abolfazli said. “This seems to have been a bit more difficult to implement.”