New York native Lori Berenson, who is serving a 20-year sentence in Peru for collaborating with leftist guerrillas in the 1990s, is four weeks pregnant, her father says.

“It’s a euphoric feeling for us,” Mark Berenson, a former college professor, told the AP on Tuesday.

Lori Berenson, 38, is married to Anibal Apari, a paroled member of the Cuban-inspired Tupac Amaru Revolutionary Movement, whom she met in jail.

Her father said the prison allows conjugal visits, but he has not had the chance to speak with Apari since news of the pregnancy.

A former Massachussets Institute of Technology student, Lori Berenson was arrested in November 1995 and a military court sentenced her the following to life in prison. A civilian court retried her in 2000, convicting her of the lesser crime of terrorist collaboration and reducing her sentence.

The Inter-American Court of Human Rights, the legal arm of the Organization of American States, upheld the civilian court’s ruling in 2004, closing Lori Berenson’s last avenue to formally appeal her sentence.

She denies any wrongdoing and maintains she is a political prisoner.

The AP obtained a signed declaration from Berenson’s prison doctor saying the pregnancy was detected during medical tests on Berenson’s ailing back.

“Lori has had health issues. We don’t know how the pregnancy will affect someone” with a back ailment, her father said by telephone in New York City.

Prison officials say Berenson suffers from herniated disks in her back and loss of hearing in one ear. She is scheduled for release in November 2015.

Prisoners in Peru typically raise their children in jail until the age of three, when they are required to be sent to family members.

The MRTA _ best known for its four-month takeover of the Japanese ambassador’s residence in 1996 in Lima _ and the larger Shining Path rebel group plunged Peru into chaos in the 1980s and early 1990s.

But unlike the bloodier, Maoist-inspired Shining Path, which was known for wholesale massacres, the MRTA cultivated a Robin Hood image, distributing food from hijacked trucks in poor neighborhoods.

___

Associated Press writer Kiley Armstrong in New York contributed to this report.