Hunched over a sewing machine, Jennipher Alupot is an unlikely poster girl for the women's rights movement. In fact, the young Ugandan mother is totally unaware of how her story - almost too horrific to be believed - has caused waves across the country and down the corridors of power, ultimately giving thousands of abused women the chance of justice.

For seven years, Jennipher was forced to breastfeed the puppies of her husband's hunting dogs. After drinking heavily, Nathan Alowoi would appear at the marital bed, bind his young wife's legs and hands together and force the mewling animals to her nipple.

He had handed over two cows to his father-in-law as part of the "bride price" for his new wife. So, he reasoned, if the cows were no longer around to provide milk then his new purchase would have to provide for the pups. "I had to feed them all through the night; then in the morning he would untie me," his wife, now 26, explains matter-of-factly.

Her ordeal began in the rural east in 2002 with the arrival of her first-born, a daughter called Achom. There was a reprieve with the second child, a boy named after his father as tradition dictates and thus protected from the indignity of having to share his mother's breast with the puppies. But when the third child, another son, Olinga, was born, a new litter was brought to suckle.

That baby, she recalls, started having fits and foaming at the mouth. Olinga died just before his second birthday. "I think it could have been something to do with the dogs," his mother says.

Jennipher had tried to resist her husband before and had alerted her own family, her in-laws and tribal elders to her suffering. She had even dared to go to the police in the nearest town, Pallisa. All in vain.

After her baby son's death, she hoped her husband's perversion might at least end. Then this March, she gave birth to another daughter, Apunyo, and the abuse started once more, only more violently. One night when she protested, her husband pierced her with a spear under the chin.

This time she snapped. She fled to the women's refuge in Pallisa. Not only did the centre give Jennipher and her baby daughter a roof over their heads, but they are also helping her bring legal action against her husband.

The case made front-page headlines around the East African nation, with commentators lining up to denounce the shocking abuse. A bill to tighten domestic violence laws that had been languishing in the Ugandan parliament for years was rushed through last month. "That bill was passed because of Jennipher," said Caroline Odoi, ActionAid's co-ordinator in Pallisa. "Her case opened so many people's eyes."

"The women's movement built up the pressure very effectively," agreed Sylvia Tamale, the dean of law at Makerere University in the capital, Kampala. "Our Government generally just pays lip service to women's rights; they only take action when it becomes politically expedient."

Domestic violence against women is widespread in Uganda. According to a 2006 Government survey, more than two in three women have suffered some form of abuse at the hands of a spouse.

Mifumi, a group campaigning for women's rights in the country, believes the "bride price" practice is a leading contributor to the spiralling levels of domestic violence in Uganda.

Tribal custom dictates that a prospective husband sends a delegation to his chosen bride's home. Her family then set a value on their daughter's worth, usually expressed in a mixture of livestock and shillings. "Bride price renders the notion that a man has purchased a wife, including her sexual consent, labour and obedience," says Atuki Turner, Mifumi's director.

At the women's refuge in Pallisa, legal officer Hope Iceduna sees first-hand the legacy of this custom: a steady stream of women arriving at her office. There was Florence, thrown out of her home after telling her husband of many years she was HIV-positive. He then demanded a refund of the bride price, but the cattle had long since died, the money long since spent; so instead he tried to appropriate some of her father's land. There was Annette, "inherited" by the brother of her deceased husband, because the family still considered her their property; and Grace, whose in-laws tried to seize her marital home once her husband died.

The bride price can often complicate efforts to get justice for mistreated and dispossessed women. Sometimes a magistrate can rule that a bride price must be refunded, before the case will even be heard.

The women's centre in Pallisa was established in June 2008. From then until the beginning of 2009, it dealt with 79 complaints, an average of 13 a month. Most of the complaints are resolved through mediation in Iceduna's office, where the parties in dispute set out their case. A dozen or so have made it to court.

ActionAid has been campaigning at the regional level, working with the district's tribal leaders to draw up a revised charter of traditional customs. One of the key goals is to transform the "bride price" into a "bride prize". "If it's a gift there are no strings attached and it is not refundable," Odoi, the charity's point person in Pallisa, explains.

At one recent meeting, around 40 clan heads gathered in a church to discuss marriage practices. Item number one on the agenda was the age girls should marry and the minimum age for losing their virginity. Next came the issue of female inheritance and the traditional tasks around the home that should be passed on from mother to daughter alongside formal schooling.

The eighth point for discussion read: "There should be NO bride price but a non-refundable bride prize."