COPENHAGEN -- A Danish court has sentenced a 36-year-old woman to four years in jail for having drained 500 millilitres (more than a pint) of blood from her young son as often as once a week over a five-year period.

The court in Herning, western Denmark, says the woman -- a trained nurse -- performed 110 drains using a catheter on the boy between the ages of 1 and 6, and told hospital doctors that his low blood count was due to a rare bone marrow disease.

The court said Thursday that doctors got suspicious and alerted police, who secretly filmed her.

A court-ordered psychiatric report said she suffers from Munchausen syndrome by proxy, a mental condition where caregivers make a child ill in order to attract attention to themselves.

The woman was not identified.