Funding for this research was provided by:
CONACYT (31034-M, 41708, 13915)
UC MEXUS-CONACYT (CN-13-571)
CONACYT/Red Temática en Salud Ambiental Infantil (F0003-2017-03/000000000280296)
Text and Data Mining valid from 2019-02-28
Received: 7 September 2018
Accepted: 22 February 2019
First Online: 28 February 2019
Ethics approval and consent to participate
: This study had the approval of the Ethics Committee of the National Institute of Public Health. Each participant, once informed of the objectives of the study, signed a letter of informed consent. Consent was also obtained for children once the postnatal follow-up began.
: Not applicable.
: The authors declare that they have no competing interests.
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