Is Zeta-Jones getting treated for bipolar disorder?

London: Welsh actress Catherine Zeta-Jones has reportedly registered at a treatment centre for her bipolar disorder.

The 43-year-old actress, who won the Academy Award for best supporting actress for 'Chicago', checked in Monday. She is expected to complete a 30-day programme there, tmz.com reports.

A source close to the actress said: "Zeta-Jones' stint in the treatment center is a proactive measure."

Another source said: "It's maintenance."

Zeta-Jones had been to the treatment center in 2011 as well, and that time her representative had said: "Zeta-Jones had made the decision to check in to a mental health facility for a brief stay to treat her Bipolar II disorder."

The actress made her last public appearance April 22 on the red carpet of the 40th Anniversary Chaplin Award Gala at Lincoln Center, New York with her actor-husband Michael Douglas.