Received: 3 January 2020
Accepted: 21 December 2020
First Online: 5 January 2021
Ethics approval and consent to participate
: The study was approved by the Reproductive Medicine Ethics Committee of the Second Affiliated Hospital of Nanjing Medical University (serial number: KY 01; date: November 2, 2014). All participants were informed of the three stimulation protocols after counseling for infertility treatments and IVF procedures.
: Not applicable.
: The authors declare that they have no competing interests.