ISRCTN63112626.

Study name	Effect of endometrial injury on repeat implantation failure following in vitro fertilisation embryo transfer or frozen embryo transfer: a randomised controlled study
Methods	RCT
Participants	Inclusion criteria: patients with repeated implantation failure (3 or more) undergoing in vitro fertilisation embryo transfer (IVF‐ET) or frozen embryo transfer (FET); patients with normal preoperative routine checks; patients ≤ 40 years of age with basal follicle‐stimulating hormone (FSH) < 10 IU/L and > 5 follicles in bilateral ovaries; patients without history of uterine cavity operation within 2 months Exclusion criteria: patients with hydrosalpinx; patients with history of endometrial adhesion; patients with uterine malformation; patients with acute genital tract inflammation; patients with history of using hormone such as oral contraceptive within 3 months
Interventions	Intervention: endometrial scratching on fifth day after ovulation before IVF or FET cycle in study group. No extra administration before IVF or FET cycle in control group Control: no intervention
Outcomes	Clinical pregnancy
Starting date	November 2011
Contact information	Prof. Caihong Ma: no contact details provided
Notes	Trial registration status on3 July 2020. No longer recruiting Investigator emailed multiple times, however have not received any reply from the researchers and could not locate any publication