Breastfeeding in America isn’t easy but it got a whole lot easier after the Affordable Care Act passed in 2010.

Lesley Muldoon, a 37-year-old mother of three in Washington, learned just that with the birth of her son two and a half years ago. Because of the law, she was able to get a free breast pump, and that smoothed her transition going back to work.

Even though her insurance provider, CareFirst, wouldn’t cover the cost of the hospital-grade breast pump she needed to feed her twin girls six months ago, she said, “Overall, I’ve had pretty good experiences with the insurance company. Being able to pump allowed me to return to work after both pregnancies and maintain a breastfeeding relationship with all my children, even if it’s not ideal for the twins.”

That’s because the Affordable Care Act (ACA), also known as Obamacare, included provisions aimed at supporting mothers who want to breastfeed, as part of its expansion of preventive-health services coverage. The regulations — and how they are applied by companies — haven’t been perfect, and some women have fallen through the cracks.

But in recent years, several studies have shown that the provisions — giving moms access to lactation consultants, breast pumps, and time and space at work to pump their milk until as late as a year after birth — have contributed to rising breastfeeding rates in the US.

The ACA’s regulations went into effect in 2010 and 2012. From 2011 to 2014, the rate of women who were breastfeeding 12 months after giving birth rose from 27 percent to 34 percent, according to the Centers for Disease Control and Prevention. That amounted to the largest increase in any recent three-year period.

Now women’s health and breastfeeding advocates worry that we might be poised for a reversal of this trend.

The July news that the administration of President Donald Trump undermined breastfeeding at a United Nations global health meeting and aligned itself with the $70 billion baby formula industry has sent a powerful signal that expanding breastfeeding access won’t be a priority for his administration. Caitlin Oakley, a national spokesperson for the Department of Health Human Services, told Vox, “The United States was fighting to protect women’s abilities to make the best choices for the nutrition of their babies. Many women are not able to breastfeed for a variety of reasons,” she said. “These women should not be stigmatized.”

In addition, the administration’s focus on sabotaging the ACA doesn’t bode well for breastfeeding rates. It means that fewer people will access health care and insurance companies can now sell skimpier, short-term plans with few benefits and protections (such as coverage for preventive services like breastfeeding support).

“When it comes to the ACA, nothing is beyond the scope of [the administration’s effort of] trying to undermine the principle of expanded coverage,” said Boston University maternal health expert Eugene Declercq. And that means even meddling with provisions that help moms feed their babies.

The ACA has helped more moms breastfeed and for longer periods

The reason raising breastfeeding rates initially became a policy focus of the ACA is quite simple: Breastfeeding represents the gold standard in infant nutrition. It basically offers inoculation against sickness and death for babies — and moms too.

Medical organizations, including the World Health Organization and the Academy of Pediatrics, recommend that babies be exclusively breastfed for the first six months of their lives — and that they should then receive breast milk, supplemented by other foods, for about two years afterward. The longer babies receive breast milk in their first years, the better.

Yet the rates of breastfeeding in the United States aren’t nearly as high as they could be. In the US only a little more than half of all babies receive any breast milk at the age of 6 months. One reason for that is women don’t get to breastfeed for as long as they want.

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The ACA tried to address that particular problem. Section 2713 of the law requires health insurance plans to provide coverage for breastfeeding support (like lactation counseling) and supplies (such as breast pumps) without any co-payments, deductibles, or co-insurance, as long as a woman opts for breastfeeding. This coverage is required for employer-sponsored plans, individual plans purchased through the Obamacare marketplaces, and for Medicaid enrollees who access public coverage through the ACA’s Medicaid expansion.

Section 4207 of the ACA also requires that companies with annual sales of more than $500,000 provide break times and a private place (not including a bathroom) where moms can use breast pumps to express their milk at work.

Researchers have been looking at what these requirements have done for breastfeeding — and their findings all point in the same direction: They have helped.

A 2018 study in the American Journal of Public Health found the ACA’s policy change was associated with a 10 percent increase in the length of time that women breastfed. The policy also increased 21 percent the length of time moms breastfed exclusively, instead of supplementing breast milk with formula or another food. A 2016 study in Women’s Health Issues discovered that women who had access to both to a break time and private space for breastfeeding were 2.3 times as likely to be exclusively breastfeeding six months after their child’s birth as compared with women who didn’t have such access.

Other researchers have found that the lactation-support coverage increased the number of women who started breastfeeding about 2.5 percentage points, “which represents as many as 47,000 more infants for whom breastfeeding was initiated in a given year in the United States.” They also found that claims for breast pumps rose significantly after the ACA’s passage.

This findings square with what people who work in the breastfeeding advocacy arena told me. Gina Caruso, deputy director of the Breastfeeding Center for Greater Washington, a lactation consulting nonprofit in Washington, estimated that her group found a threefold increase in lactation consultations following the ACA’s passage and that the average number of appointments women receive has climbed. Her group also detected a drop-off in the clinic’s breast-pump sales (since women were able to get their pumps for free from their insurance companies). “The ACA has changed our business immensely,” she said.

But the law hasn’t been perfect

I also heard that the ACA’s breastfeeding policies have been far from perfect: Some families have had trouble finding lactation consultants in their networks or have wound up with as much as $1,500 in unreimbursed claims.

One woman said she submitted her claims to Cigna for lactation consultation, and even though her paperwork was clearly marked as being for lactation, Cigna told her the service was related to parenting and wouldn’t be covered. (Cigna said in a statement to Vox that coverage of lactation consultants is required by law and that it normally covers such services.)

Another woman told me she couldn’t get her lactation consultant services covered, even after she had her doctor send a note to the insurance company for preauthorization. “They repeatedly denied the claim until I got my office HR involved,” she said in an email. (Both women did not want to be publicly identified.)

Mara Gandal-Powers, of the National Women’s Law Center, explained that these stories are not uncommon. Because lactation consulting is a service that women need immediately after birth, they’re not typically in a position to haggle with insurance companies over coverage. “If you don’t get the services to help you increase your [breast milk] supply quickly, nursing can become difficult or impossible and not really happen. So we see women who pay out of pocket.”

Trump’s chipping away at the ACA will affect women’s health

Instead of working to fix these gaps in coverage, the Trump administration has been attempting to dismantle the ACA. And while Republicans have failed to fully repeal the law, they’ve put forward a series of policies that have caused the uninsured rate to rise and have weakened the law in the process.

Among them are the following: In June, the administration announced that insurance companies can now offer skimpier, short-term plans that don’t have as many benefits and protections, including coverage for the preventive care and coverage for basic services that Obamacare ensured.

Breastfeeding is a “preventive service,” said Kaiser’s Salganicoff. “So if it’s a short-term plan, it doesn’t have to have maternity care, preventive services and women who enroll in these plans would not have the entitlement to the breastfeeding coverage.”

Companies have also been scaling back their reimbursements. In April Anthem, which is the nation’s second-largeest health insurer, reduced its reimbursement for breast pumps from $169 to $95. Critics see the move as potentially undermining Obamacare’s breastfeeding mandate. “The question is what types of pumps will now be provided,” said Summer Hawkins, a researcher at Boston College School of Social Work who has studied the impact of the ACA on breastfeeding.

In a statement, Anthem said, “Anthem recognizes the positive health benefits that breastfeeding can have on mothers and their newborns, and we are committed to ensuring new mothers have the information, tools and support they need to successfully breastfeed their newborns.” Anthem did not answer repeated questions about why it has reduced its reimbursement rate.

One thing the ACA hasn’t helped with when it comes to breastfeeding rates is socioeconomic disparities. “There’s a 20 percent gap between most and least educated,” Hawkins added. African-American women also have persistently low rates of breastfeeding compared to other racial groups. “So while our average rates look fantastic now, once you start digging into this by education, income, or [insurance] status, you see lower income, less educated women have much lower rates of breastfeeding than more advantages women.”

Let’s not forget that the US remains unique among wealthy countries in not having a maternal leave policy. “The ACA did some very important things but I would say it’s only a piece of the broader constellation” of measures that would improve women’s and infant’s health, said Carol Sakala, director of childbirth connection programs at the National Partnership for Women & Families.

And when it comes to breastfeeding, Sakala said, “It’s hard to find another more impactful preventive health practice. We as a society should be mobilized to be supporting women and babies to get benefits of breastfeeding.”

For more on breastfeeding politics, please listen to the July 12th episode of Today Explained.