Jordi Clotet, Begoña Loureiro, Mª Jesús Cabero Perez, Elisa Llurba Olivé, Maria José Solana, Myriam Perez Gruz, Miguel Saenz de Pipaon, Elvira Larqué Daza, Talía Sainz, Sergi Fernandez Gonzalez, Isabel Iglesias-Platas, Vicente Andreu-Fernández, Anna Parra-Llorca, Gerardo Martínez, Jesús López-Herce, Leopoldo Martinez, María Gormaz, Iris Iglesia, Sebastian Sailer, Fernando Cabañas, Máximo Vento, María D. Mesa, Dolores Gómez Roig, Oscar García Algar, Diana Escuder-Vieco, Carmen Rosa Pallás-Alonso, Cristina Calvo, María Sánchez-Campillo, Rosa Aras, UAM. Departamento de Pediatría, UAM. Departamento de Farmacología, Instituto de Investigación Sanitaria Hospital Universitario de La Paz (IdiPAZ), [Mesa,MD] Department of Biochemistry and Molecular Biology II, Institute of Nutrition and Food Technology 'José Mataix', Biomedical Research Center, University of Granada, Granada, Spain. [Mesa,MD] ibs.GRANADA, Instituto de Investigación Biosanitaria, Complejo Hospitalario Universitario de Granada, Granada, Spain. [Loureiro,B] Neonatology Unit, University Hospital Cruces, Biocruces Bizkaia Health Research Institute, Barakaldo, Spain. [Iglesia,I] Growth, Exercise, Nutrition and Development (GENUD) Research Group, Universidad de Zaragoza, Zaragoza, Spain. [Iglesia,I, Rodriguez Martinez,G] Instituto de Investigación Sanitaria Aragón (IIS Aragón), Zaragoza, Spain. [Fernandez Gonzalez,S, García Algar,O, Gómez Roig,D, Perez Gruz,M, Andreu-Fernández,V, Clotet,J, Sailer,S, Iglesias-Platas,I] BCNatal-Barcelona Center for Maternal-Fetal and Neonatal Medicine (Hospital Sant Joan de Deu and Hospital Clínic), Barcelona, Spain. [Fernandez Gonzalez,S, Iglesias-Platas,I] Institut de Recerca Sant Joan de Déu (IR-SJD), Barcelona, Spain. [Llurba Olivé,E] Obstetrics and Gynecology Department, High Risk Unit, Sant Pau University Hospital, Barcelona, Spain. [Llurba Olivé,E] Women and Perinatal Health Research Group, Biomedical Research Institute Sant Pau (IIB-Sant Pau), Sant Pau University Hospital, Barcelona, Spain. [Llurba Olivé,E] School of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain. [García Algar,O, Sailer,S]Neonatology Unit, Hospital Clinic-Maternitat, ICGON, BCNatal, Barcelona, Spain. [Solana,MJ, López-Herce,J] Servicio de Cuidados Intensivos Pediátricos, Hospital General Universitario Gregorio Marañón, Departamento de Salud Pública y Materno infantil, Universidad Complutense de Madrid, Madrid, Spain. [Cabero Perez,MJ] Hospital Universitario Marqués de Valdecilla, Santander, Cantabria, Spain. [Sainz,T, Calvo,C] Servicio de Pediatría, Enfermedades Infecciosas y Tropicales, Hospital La Paz, Madrid, Spain. [Sainz,T, Martinez,L, Aras,R, Calvo,C]Instituto de Investigación Hospital la Paz (IdiPAZ), Madrid, Spain. [Sainz,T, Calvo,C] Red de investigación Traslacional en Infectología Pediátrica (RITIP), Madrid, Spain. [Martinez,L] Servicio de Cirugía Pediátrica, Hospital La Paz, Madrid, Spain. [Escuder-Vieco,D, Pallás-Alonso,C] Donated Milk Bank, Health Research Institute i + 12, University Hospital 12 de Octubre, Universidad Complutense, Madrid, Spain. [Parra-Llorca,A, Vento,M, Gormaz,M] Neonatal Research Group, Health Research Institute La Fe, University and Polytechnic Hospital La Fe, Valencia, Spain. [Sánchez-Campillo,M, Larqué Daza,E] Department of Physiology, Faculty of Biology, University of Murcia, Murcia, Spain. [Rodriguez Martinez,G] Department of Pediatrics, Faculty of Medicine, Hospital Clínico Universitario Lozano Blesa, Zaragoza, Spain. [Iglesias-Platas,I] Neonatology Unit, Hospital Sant Joan de Déu, Institut de Recerca Sant Joan de Déu, BCNatal, Barcelona, Spain. [Saenz de Pipaon,M] Department of Neonatology La Paz University Hospital, Madrid, Spain. [Calvo,C] European Network of Excellence for Pediatric Clinical Research, Bari, Italy. [Cabañas,F] Department of Paediatrics-Neonatology Quironsalud, Madrid University Hospital and Biomedical Research Foundation-IDIPAZ, La Paz University Hospital, Madrid, Spain., This research was funded by the PN I+D+I 2008–2011 (Spain), ISCIII- Sub-Directorate General for Research Assessment and Promotion and the European Regional Development Fund (ERDF), RETICS Maternal and Child Health and Development Network, SAMID Network, Ref. RD16/0022/0015. Anna Parra-Llorca acknowledges Rio Hortega grant CM18/00165 from the Instituto de Investigación en Salud Carlos III (Ministry of Science, Universities and Innovation, Kingdom of Spain), Talía Sainz is funded by The Instituto de Salud Carlos III- Spanish Ministry of Science and Innovation cofounded by FEDER (EU). (Grant nº JR16/00021), and Cristina Calvo is a member of the IdiPAZ Research Institute, Madrid. Spain. Translational Research Network for Pediatric Infectious Diseases (RITIP), Madrid, Spain. TEDDY Network Member (European Network of Excellence for Pediatric Clinical Research, Bari, Italy).