A woman who played a key role in the roll-out of Obamacare—and oversaw the massive government-run Medicare and Medicaid programs—unexpectedly resigned Friday after two often-tumultuous years..
Marilyn Tavenner, administrator for the federal Centers for Medicare and Medicaid Services, emailed staffers Friday to tell them she will leave her post at the end of February.
Tavenner's exit will come two weeks after the close of the second open-enrollment season for Obamacare health insurance plans.
Her boss, Health and Human Services Secretary Sylvia Burwell, credited Tavenner on Friday with being "a big part of the reason why, as of this past spring, roughly 10 million Americans had gained health coverage since last year—the largest increase in four decades."
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Tavenner will be replaced as administrator on an interim basis by Andy Slavitt, the former top Unitedhealth Group executive who is currently second-in-command at CMS.
In an email to CMS staff Friday, Tavenner wrote, "It is with sadness and mixed emotions that I write to tell you that February will be my last month serving as the administrator for CMS. I have great pride and joy knowing all that we have accomplished together since I came on board five years ago in February of 2010."
Tavenner did not say why she is stepping down, and her departure came as something of a surprise.
But an HHS official noted, "She has been working a 24/7-job for five years. She plans to take some time off and then will look at the opportunities ahead of her."
A former executive at the Hospital Corporation of America who had begun her career as a nurse, Tavenner joined CMS in 2010. She was confirmed as head of the agency, which has an $820 billion budget, in May 2013 after serving as principal deputy administrator, and then acting administrator.