Deepika 2016.

Methods	Prospective randomiSed, double‐blinded, proof of concept study was conducted in a tertiary care centre from August 2013 to December 2015 in 304 RIF cases defined as 2 previous failed embryo transfers (fresh or frozen) with transfer of at least four good‐quality embryos (grade I)
Participants	147 women less than 37 years who have had two previous IVFs.
Interventions	Study group 1: endometrial stimulation (ES) was by Pipelle biopsy on day 4‐6 of transfer cycle; n = 49 Study group 2: endometrial stimulation (ES) was performed on day 20‐22 of previous cycle; n = 49 Control group: no endometrial stimulation (ES) in previous 3 cycles; n = 49
Outcomes	Clinical pregnancy
Notes	Trial was not registered. It was not possible to extract review outcomes from the abstract (only P values provided), author correspondence unsuccessful, last attempted 03/07/2020.