Pop icon Madonna failed in her bid to adopt a second child from Malawi after a court Friday rejected her application, warning that the case could open the door to trafficking in children.

Madonna did not attend the closed-door court hearing in the administrative capital Lilongwe, and her lawyer did not speak to reporters as he left.

Judge Esmie Chondo's ruling addressed widespread concerns that by facilitating international adoptions, Malawi's courts could inadertently expose the nation's children to the threat of human traffickers.

"I must confess that there's a gripping temptation to throw caution to the wind and grant an adoption in the hope that there will be a difference in the life of just one child," she said.

"By removing the very safeguard that is supposed to protect our children, the courts by their pronouncements could actually facilitate trafficking of children by some unscrupulous individuals," she added.