Funding for this research was provided by:
Instituto de Salud Carlos III (COV20/00021)
Received: 21 October 2020
Accepted: 22 March 2021
First Online: 1 April 2021
: All procedures were approved by the Drug Research and Clinical Research Ethics Committee of the Puerta de Hierro University Hospital (Madrid, Spain) on 23rd March 2020 (protocol registration number, 55/20); each collaborating center subsequently obtained protocol approval locally (Ethics Committees of the participant hospitals, listed in the Supplementary Table 1 of the Additional File InternalRef removed). Upon recruitment, mothers consented to participate in the study by either signing a document, when possible, or by giving permission verbally which was recorded in the patient’s chart in the electronic clinical recording system. The possibility of verbal consent was approved by the Ethics Committees during the first three months of the pandemic, given the contagiousness of the disease and the lack of personal protection equipment; afterwards, written consent (using the Patient Consent Form, Additional File InternalRef removed) was collected from every patient who had previously given permission verbally.
: Not Applicable.
: The authors declare that they have no competing interests.