Funding for this research was provided by:
JSPS KAKENHI (Grant Number 16K12141)
Received: 28 August 2017
Accepted: 5 December 2017
First Online: 5 February 2018
Ethics approval and consent to participate
: The Ethical Committee of Kyoto University Medical School approved the study (Approval number R0153). Responses to the questionnaire from the maternity homes were considered informed consent. The anonymity of the participants was preserved.
: Not applicable
: The authors declare that they have no competing interest.
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