(CNN) Rep. Phil Roe announced on Friday that he will retire from Congress at the end of the year, joining more than 20 other House Republicans who also plan to head for the exits after the 2020 election.

"As someone who practiced medicine for over 30 years, I said I would serve five or six terms because I never intended this job to be a second career. After prayerful consideration, I have decided to retire at the end of the 116th Congress," Roe said in a statement obtained by CNN.

Roe, a retired OB/GYN, also served as mayor of Johnson City, Tennessee, before running for Congress. He is currently serving his sixth term in the House.

His retirement is not surprising given his previous comments about how long he planned to be in office.

The district he represents -- Tennessee's 1st congressional district -- is a longtime Republican stronghold, and it is likely to remain so. Roe won reelection with about 77% of the vote in 2018.

In his statement, Roe said he is "confident East Tennessee is full of capable public servants who will step up to fill my void, and I am ready to give them the opportunity to do so."

During his time in the House, Roe focused on veterans' issues. He is the top Republican on the House Committee on Veterans' Affairs, and he previously served as chairman of the committee.

He was also outspoken on health care, pushing against the Affordable Care Act after it was signed into law during his first term in Congress.

CORRECTION: This story has been updated to correct the 2018 election results in the Tennessee 1st.