1. Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
2. Municipal Institute of Medical Research (IMIM-Hospital del Mar), Barcelona, Spain
3. CIBER Epidemiología y Salud Pública (CIBERESP), Spain
4. Department of Maternal-Fetal Medicine, ICGON (Institut Clínic d´Obstetrícia, Ginecologia i Neonatologia), Hospital Clinic-IDIBAPS (Institut d´Investigacions Biomèdiques Agustí Pi i Sunyer), University of Barcelona, Barcelona, Spain
5. Pompeu Fabra University, Barcelona, Spain