MULTISCAN--a Scandinavian multicenter second trimester obstetric ultrasound and serum screening study.

F S Jørgensen, L Valentin, K A Salvesen, C Jørgensen, F R Jensen, J Bang, S H Eik-Nes, Mette Madsen, K Marsal, P H Persson, J Philip, J W Bogstad, B Nørgaard-Pedersen