South African anti-apartheid leader Winnie Madikizela-Mandela is expected to have back surgery Thursday after complications arose from a previous surgery.

Madikizela-Mandela had a similar procedure in March, a spokeswoman said on Tuesday, according to Reuters report in BusinessInsider.

The former first lady and wife of the late Nelson Mandela, was hospitalized on March 7, had surgery on her back the following day and is due for a follow-up operation, her spokeswoman Zodwa Zwane said in a statement.

During Mandela’s 27 years in prison, Madikizela-Mandela fought for his release and for the rights of black South Africans under white minority rule. She was arrested, banished and detained, Reuters reported.

Sources close to Madikizela-Mandela say she’s been hospitalized for weeks, and has been hospitalized several times in recent years with diabetes, EyewitnessNews reported.

Her diabetic condition prevented doctors from performing the surgery she needs.

Friends said she became ill after the Mthatha High Court dismissed her claim to her former husband’s home in Qunu. Others said she was in hospital before the Mthatha judgment was issued last week.

On April 7 the Eastern Cape High Court dismissed Madikizela-Mandela’s 2014 claim of ownership to Mandela’s Qunu village home, located in the Eastern Cape province, according to AfroAmerican.

Madikizela-Mandela argued that the home belonged to her under customary law because it was purchased in 1989 while she and Nelson Mandela were still married, according to BBC.

She was married to Mandela for 38 years. Although they were still married when he became president in May 1994, the couple had separated two years earlier. Their divorce was finalized on March 19, 1996.

Mandela became South Africa’s first black president in 1994. When he died in 2013 at age 95, he bequeathed the property to his family. He left Madikizela-Mandela out of the will.

In his will, Mandela left all his assets to family members, personal staff, schools and the ruling African National Congress party, but did not include Madikizela-Mandela.

Mandela spent much of his childhood in Qunu, and returned there often after retirement. He said he wanted the Qunu homestead to “be used by my family in perpetuity in order to preserve the unity of the Mandela family.” Mandela was buried in Qunu in 2013.

After the court ruling, the Mandela family said in a statement that they were grateful that “the saga has now come to a close and trusts that Winnie will make peace with the judgement.”

Mandela married his third wife Graca Machel, the widow of Mozambique President Samora Machel in 1998, a year before he stepped down as president in 1999.

The court ruling could undermine customary law and have repercussions for the rights of widows in the cases of deceased estates, said Nokuzola Mndende, director of the Icamagu Institute, which teaches African traditional religion, IndependentOnline reported.

Mandela’s palatial Qunu  home was built on land that was awarded to Madikizela-Mandela by the area’s tribal authority by virtue of her being a bride to the clan, Mndende said.

“Here (in South Africa) we have two laws — Roman and customary. The latter was meant to protect people in cases like this one,” Mndende said. “The government contradicts itself because when it comes to applying the two laws, the Western law supersedes the customary law.