In 2006, the Israeli photojournalist Jonathan Torgovnik went to Rwanda for Newsweek to do a story on the HIV epidemic in Africa. During his research he met some Tutsi women who had been raped during the 1994 genocide, then contracted HIV and had given birth. Investigating further he discovered that there are around 20,000 children of rape living in the country. Torgovnik decided to embark on a project of his own to document the lives of these women and children. Joseline Ingabire ( right), whose portrait with her two daughters is one of the four shortlisted photographs in this year’s National Portrait Gallery Photographic Portrait Prize exhibition that begins on Thursday, was one of the women willing to tell her story and be photographed.

“The militia came to her home and murdered her husband in front of her,” says Torgovnik. “She was pregnant at the time, but they raped her then and there and they raped her repeatedly throughout her pregnancy. Right after she had given birth to a daughter they raped her again. She became pregnant again and a second daughter was born within a year. One is born from love, one from rape.”

Ingabire had not told her story to any outsider before. She has not yet even told her two daughters, who are now 11 and 12 years old, but she wants the facts to be known outside Rwanda. “She felt hugely vulnerable and ashamed. She has been ostracised by her community, and rejected by her own family, who said that they would accept her without her younger daughter, but that they could not accept her with the girl, because she is the daughter of a murderer. This woman has been through so much – and is still going through so many layers of trauma – that it’s hard to understand how she manages to survive at all.”

Torgovnik asked Ingabire and her younger daughter to stand in front of their house to be photographed, and then he realised that the older daughter wanted to be part of it, too. “I told them all just to stand as naturally as possible and simply behave as they normally would. They were very nervous and stiff while I exposed the first two rolls of film, and then I noticed that while I was changing my film, that was the moment when they relaxed. Eventually I managed to get them to relax in front of the camera.”

The results are extraordinary. Anyone looking at this portrait with no prior knowledge of their story will pick up on some level of trauma. You cannot know exactly what it is, but it is there in Ingabire’s mouth and the direct gaze of her eyes, in the tight muscles of the eyebrows. There is enormous strength and determination in that face but, more than that, there is vulnerability beneath the surface.

It may be pure coincidence, but all four portraits shortlisted this year depict young women coping with varying degrees of personal trauma, and betraying in each case a vulnerability that overrides their projected strength.

LUCILA a.m. BY JULIETA SANS

Sans is a 28-year-old Argentine photographer based in London. She went back to Buenos Aires recently to continue a long-term project recording the lives of her friends in the quiet intimacy of their everyday rituals. Lucila a.m. portrays a close friend at home in the city as she prepares for the day.

“I like photographing people in their domestic environment. I never pose people, but just observe and sometimes gently direct, so this was a very ordinary situation of Lucila having breakfast. In Argentina, middle-class children are born and grow up in the city and often live with their parents until they are quite old. In this picture, Lucila is trying to decide whether to leave home or not. She’s still kind of clinging on to her teenage years.”

While Lucila is clearly a grown woman, there are elements of her character, of her vulnerability and immaturity that come through in her pose, in her haircut, her facial expression. “She’s feeling insecure and vulnerable. She’s lingering between her teenage years and adulthood. She’s feeling very uncertain about herself at the moment, and I think that comes through in the portrait.”

JANINE BY MICHELLE SANK

Sank’s entry is taken from the photo series Photo Crossings, Germany, which documents a day-care centre for troubled teenagers in Mannheim. “As soon as I saw Janine, I knew there was something different about her. She was one of the teenagers who stay in the centre, whose parents take no interest in them. I sensed a kind of hardship in her face. She seemed so tough and self-assured, and made no attempt to cover up the scars on her arm. It was as if she wanted them to be noticed.” Her face depicts a mix of defiance and vulnerability. You quickly detect her pretence of being tough, almost macho, in her pose before a female photographer, but underneath is the vulnerability of a very sad girl who is having to go through adolescence while trying to deal with the fact that her parents don’t love her.

Sank’s composition worked, she says, “unbelievably well” that day. “The cloud formations in the sky were just right, and the light was right. I knew it was just one of those moments when everything worked.”

ALICE & FISH BY DAVID STEWART

I am glad to report that a touch of levity has been allowed into the shortlist in the form of a lovely portrait by David Stewart of his 14-year-old daughter, Alice, with a fish. “She was in her ‘emo phase’ at the time, a music linked with a wave of bands such as My Chemical Romance. It was all about being a teenager suffering in your bedroom. She and all her friends were into black clothes and black eyeliner, and they moped around looking all miserable and tortured and stroppy the whole time.

So I decided to poke fun gently at her and her friends.”

Stewart photographed Alice on Morecambe Bay during a visit to his home town of Lancaster. “I wanted to capture the miserable expression of the fish with my daughter in her miserable phase. Actually, I think what comes through is her shyness and her defiance at the same time.”

The Photographic Portrait Prize, National Portrait Gallery, London WC2 (www.npg.org.uk 020-7306 0055), from Thur. The exhibition will be at The Lowry in Salford next summer

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