That pullback may have contributed to the first-ever drop in enrollment in Obamacare plans.
On Monday, a story on the news site Talking Points Memo reported there was no sign that the Trump administration would work with outside groups this fall to encourage people to sign up for health insurance for 2018.
That's despite the fact the Affordable Care Act requires nearly all Americans to have some form of health insurance or pay a tax penalty.
Amanda Hooper, the National Women's Law Center's director of engagement and mobilization, told CNBC that "we have no indication from them that there will be reach out," as the Obama administration did with that organization every year since 2013.
"It is the silence that is speaking volumes," said Hooper, noting that the Obama administration would start reaching out to the law center and other groups in the summer to prepare for the fall enrollment season.
"We are very interested in hearing what their plans are," Hooper said of the Trump administration.
CNBC reached out to HHS and asked whether the Trump administration would end the long-standing partnership, and, if so, why.
In response, HHS spokeswoman Alleigh Marrè said, "As Obamacare continues to collapse, the administration is considering its options on how to address the challenges Americans are facing by cancelled plans, higher costs, and failing markets."
Hooper said that even if the Trump administration doesn't want help from the National Women's Law Center in boosting Obamacare enrollment, the group will continue outreach efforts on its own to potential insurance customers.
"We will be sure to get the message to clarify for people that [Obamacare] is still here, and you should still sign up ... we will let people know when to sign up," Hooper said. "Obamacare is the law of the land."
She said that in past years her group, which received no federal funding for its Obamacare promotion efforts, worked in tandem with other advocacy groups to encourage sign-ups.
One example of that was a Facebook Live event in December hosted by the NWLC, with participation from the Center for American Progress, the National Partnership for Women and Families, and Raising Women's Voices, as well as two members of the Obama administration.
"The video reached 168,000 people and has been viewed 16,000 times," Hooper said.
In addition to being coy about its open-enrollment promotion strategy, the Trump administration has refused to say whether the cost-sharing reduction, or CSR, payments will continue being made to insurers through 2018.
Those CSR payments, worth billions of dollars, compensate insurers for discounts in out-of-pocket health-care charges offered to low- and middle-income Obamacare customers.
Trump has threatened to end the CSR payments. But if the payments end, insurers would still be legally responsible for giving the discounts to qualified customers, cutting into the insurers' bottom lines.
That, in turn, would lead insurers to seek higher premiums from customers to cover their operating costs.
Late last week, the federal Centers for Medicare and Medicaid Services, which oversees Obamacare, gave insurers almost three extra weeks to submit their proposed prices for individual 2018 plans because of the lack of certainty about the CSRs. The new deadline for proposed Obamacare premiums is now Sept. 5.
Meanwhile, the nonpartisan Congressional Budget Office is expected to release a report Tuesday that will outline the risks of terminating the CSR payments. The analysis, which is being done in conjunction with the staff of the Joint Committee on Taxation, will look at the impact on the federal budget, health insurance coverage, market stability and premiums.
The Cleveland Plain Dealer on Saturday reported that insurers in Ohio have begun filing new, much-higher premium rate increase requests with state regulators in case Trump ends the CSR payments.
The newspaper noted that insurers already were asking for price hikes averaging 20 percent or more for next year. But the state insurance department asked for new requests that assume an end to CSR payments, as well as other factors.
One insurer, Molina Healthcare of Ohio, said last week that it wants to add an extra 21.4 percent average price increase on top of its existing request of a 24 percent increase, according to the Plain Dealer.
Paramount Insurance filed an average rate hike of 35.9 percent assuming an end to the CSRs, and Summa said it would need to raise prices of its most popular individual plans by an average of 41.1 percent, the newspaper said.