Funding for this research was provided by:
National Science and Technology Development Agency (None)
The Royal Golden Jubilee Ph.D. Program (Grant No. PHD/0098/2557)
The Graduate School Dissertation Funding and an Excellence Center of the Epidemiology Unit Scholarship, Prince of Songkla University (None)
Text and Data Mining valid from 2019-04-05
Received: 29 November 2018
Accepted: 27 March 2019
First Online: 5 April 2019
Ethics approval and consent to participate
: The study was approved by the Research Ethics Committee of the Faculty of Medicine, Prince of Songkla University, Thailand (REC No. 58–061–15-1). Site permissions were obtained from the directors of the Provincial and District Public Health Offices for each study setting. Written consent forms were obtained from all participating pregnant women after they received a detailed oral explanation of the study. For pregnant women aged under 18 years, the consent of guardian was waived by the Research Ethics Committee.
: Not applicable.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.