1. Department of Obstetrics, Jeanne de Flandre Hospital, CHU Lille; Lille France
2. Perinatal Environment and Growth; EA 4489, University of Lille North of France; Lille France
3. Department of Biostatistics; EA 2694, UDSL, CHU Lille; Lille France
4. Etablissement français du Sang, Nord Pas de Calais; France