"Our quake has devastated our country ... Many children have lost both their parents ... they will be more vulnerable," said Anand Tamang, director of CREHPA, a Nepalese group which campaigns against child marriage.
"There will be a dramatic increase in child marriage and trafficking, ... we know the situation will be much worse," he told the Thomson Reuters Foundation on the sidelines of an international conference on ending child marriage in the Moroccan city Casablanca.
Tamang said the risk of sexual assault on girls living in tents in Kathmandu since the quake would encourage families to marry off their daughters.
"Rape is taking place. Almost every week we have a case of a young girl being raped by a group of boys (in tents)," he said. "Parents who have young girls will have fear in their minds and they will think the best way to ensure her safety will be to marry her."
Other girls may be married off because their parents have been killed, their families can no longer afford to keep them in school or because their schools were destroyed."
Read article by Emma Batha from Thomson Reuters Foundation.