The president of Planned Parenthood has been forced out of her position after only eight months on the job.

Dr Leana Wen said in a statement she was forced out after “philosophical differences”, over the direction of the organization.

Her departure leaves the nation’s largest nonprofit provider of abortion care without a permanent president during a presidential campaign where abortion rights has already emerged as a top issue, and have been under fierce attack under the Trump administration, and at state level.

Wen first announced her departure on Twitter on Tuesday, saying the Planned Parenthood Federation of American “ended my employment at a secret meeting”. She said she and the organization had been “engaged in good faith negotiations about my departure based on philosophical differences”, at the time.

I just learned that the @PPFA Board ended my employment at a secret meeting. We were engaged in good faith negotiations about my departure based on philosophical differences over the direction and future of Planned Parenthood. My statement to come shortly. — Leana Wen, M.D. (@DrLeanaWen) July 16, 2019

“I believe that the best way to protect abortion care is to be clear that it is not a political issue but a health care one, and that we can expand support for reproductive rights by finding common ground with the large majority of Americans who understand reproductive health care as the fundamental health care that it is,” said Wen in a statement.

She said it had been “an honor and privilege to serve alongside our dedicated doctors, nurses, clinicians, staff and volunteers”, and that she would, “always stand with Planned Parenthood, as I continue my life’s work and mission of caring for and fighting for women, families and communities”.

Following Wen’s tweet, Planned Parenthood Federation of America named Alexis McGill Johnson acting CEO. Johnson is a former board member of the Planned Parenthood Action Fund, the health clinic’s political advocacy arm, and a former chair of the Planned Parenthood Federation of America.

The organization did not address the philosophical differences described by Wen. Johnson said the search for a new CEO would start early next year, with a goal to have the new president in place by the end of 2020.

In response to the announcement, McGill Johnson thanked Wen, and said: “Having been part of the Planned Parenthood family for nearly a decade, and having spent my career working in movements for social justice, I can’t think of a greater honor or more weighty responsibility than leading an organization like Planned Parenthood in this moment.”

The change leaves Planned Parenthood without a permanent president during the 2020 presidential campaign, and at a time when abortion rights have been under attack.

Republican-led legislatures have enacted unconstitutional abortion bans at the state level from Ohio to Alabama. The laws are being challenged in court, and abortion is still legal in all 50 US states.

Democratic presidential candidates made commitments to protect reproductive rights at a Planned Parenthood forum in June called WeDecide – hosted in part by Wen.

The Trump administration has made clear its intention to attack reproductive rights wherever possible. Last week, the administration won a court victory which allowed it to deny federal family planning dollars to health care providers who refer women to abortion services.

In an interview with the Guardian in November, Wen warned the women’s health was in a “state of emergency”.

“There is no question we are in a state of emergency for women’s health,” said Wen. When a society “treats one type of healthcare differently than everyone else, that’s when we get to where we are, which is the biggest healthcare crisis of our time.”

Wen previously served as the health commission for Baltimore, Maryland, and before that was an emergency room physician. She and her parents immigrated to Utah from China, her father was jailed as a political dissident before the family left. She touted her family’s own use of Planned Parenthood’s health services when arguing for the organization.

McGill Johnson was an academic, teaching at Yale and Wesleyan Universities, before she entered advocacy work in 2004. Since, she has worked in minority voter engagement, co-created racial bias training for Starbucks, in addition to her work for Planned Parenthood.