A number of insurgents were also killed in the operation in Kajaki district of the province on Saturday, it said in a statement.
"A search of the site after the exchange revealed a dead female and child in one of the rooms."
The statement did not say if there were any casualties among coalition forces.
Civilian casualties are a sensitive issue for foreign troops stationed in Afghanistan and President Hamid Karzai's government, as it feeds anger among already frustrated Afghans.
More than 520 civilians were killed last year alone during operations by NATO and coalition troops attacking the Taliban, aid groups say.
More than 50,000 foreign troops are stationed in Afghanistan. Coalition forces overthrew the country's Taliban government in 2001.
Güncelleme Tarihi: 24 Şubat 2008, 15:42