Funding for this research was provided by:
Consejo Nacional de Ciencia y Tecnología (180956)
Text and Data Mining valid from 2019-04-11
Received: 22 November 2018
Accepted: 20 March 2019
First Online: 11 April 2019
: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the reported research.
: This study was approved by the Ethics Committee of the National Public Health Institute of Mexico. All participating women signed an informed consent letter; for women under 18 years of age, in addition to their agreement we obtained an informed consent letter from their parents.
: Not Applicable.
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