This is quite an old report, but makes for very interesting (though extremely disturbing) reading.

The Hidden Gulag: Exposing North Korea’s Prison Camps
Prisoners’ Testimonies and Satellite Photographs (http://www.hrnk.org/hiddengulag/toc.html)



Published by the US Committee for Human Rights in North Korea (http://www.hrnk.org/about.html)

Excerpt:
There are sporadic reports of forced abortions and baby killings at the kwan-li-so (prisons), where, except for a very few privileged couples, the prisoners were not allowed to have sex or children. There are also sporadic reports of forced abortion and baby killings at the kwan-li-so, where sex between prisoners is prohibited. And there are sporadic reports of killings of pregnant women who were raped or coerced into sex by prison guards.also

Onsong Jip-kyul-so (Detention Center), North Hamgyong Province At Onsong, during the time of Former Detainee #25’s detention, roughly 150 persons were held in two rooms. The detainees, who were assigned to make bricks, were told that they were not human beings but dogs and pigs. They were made to sing “silly songs” in honor of Kim Jong Il. Detainees were asked the usual question: had they met any South Koreans or Christians while in China? Two women confessed to having converted to Christianity while in China and were taken away by the police agents, who told the remaining women that the two Christian converts had been executed and that the rest of the women should consider themselves warned.
(http://www.hrnk.org/hiddengulag/toc.html)