[1] Hosp Univ La Paz, Dept Neonatol, ES-28046 Madrid, Spain
[2] Hosp Univ La Paz, Dept Biostat, ES-28046 Madrid, Spain
[3] Inst Salud Carlos III, Red Salud Materno Infantil & Desarrollo, Madrid, Spain
[4] Inst Salud Carlos III, CIBER Fisiopatol Obesidad & Nutr, Madrid, Spain
[5] Hosp Infantil Univ Nino Jesus, Madrid, Spain
[6] Univ Autonoma Madrid, Inst Invest La Princesa, Madrid, Spain
[7] Univ Autonoma Madrid, Dept Pediat, Madrid, Spain