The absence of evidence is not the evidence of absence

Affiliations

• ¹ Department of Clinical Immunology and IdISSC, Hospital Clínico San Carlos, Madrid, Spain Department of Microbiology I, Complutense University School of Medicine, Madrid, Spain ssramon@salud.madrid.org.
• ² Department of Clinical Immunology and IdISSC, Hospital Clínico San Carlos, Madrid, Spain Department of Microbiology I, Complutense University School of Medicine, Madrid, Spain.
• ³ Unit of Assisted Reproduction, Centro Médico Millenium, Madrid, Spain.
• ⁴ Department of Clinical Immunology, Hospital General Universitario Gregorio Marañón, Madrid, Spain.