Ghaznavi, Cyrus
Sakamoto, Haruka
Yoneoka, Daisuke
Nomura, Shuhei
Shibuya, Kenji
Ueda, Peter http://orcid.org/0000-0002-3275-8743
Funding for this research was provided by:
Ministry of Education, Culture, Sports, Science and Technology of Japan (16H02643)
Article History
Received: 20 November 2018
Accepted: 19 March 2019
First Online: 8 April 2019
Ethics approval and consent to participate
: The study was approved by the Regional Ethics Committee at The University of Tokyo, Japan. Informed consent was not required for secondary use of data from the National Fertility Survey.
: Not applicable.
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