Article History
Received: 31 January 2020
Accepted: 1 April 2020
First Online: 13 April 2020
Compliance with ethical standards
:
: The authors declare that they have no conflicts of interest.
: This study was approved by the Ethics Committee of JISART (Japanese Institution for Standardizing Assisted Reproductive Technology), and was registered with the Japan Society of Obstetrics and Gynecology.