Abstract
Background: The displacement of window of implantation (WOI) has been proposed as an important factor contributed to RIF. However, endometrial histological dating as the diagnostic tool of endometrial receptivity has been questioned.
Methods : This is a prospective intervention trial including 205 infertile patients from July 2017 to December 2017.Endometrial biopsies from 50 good prognosis patients were conducted on day 3(n=6), 5(n=6), 7(n=26), 9(n=6) or 11(n=6) of post-ovulation (PO+3/5/7/9/11) in the previous natural cycle before their conventional frozen-thawed embryo transfer (FET) cycle. The endometrial biopsies of 155 RIF patients were conducted on day of PO +7.
Results: The verification of Noyes criterion for endometrial dating was conducted in different time (PO +3/+5/+7/+9/+11) from 41 good prognosis patients achieving ongoing pregnancy in the first conventional FET cycle after the endometrial biopsies. The agreement between two pathologists for endometrium dating in infertile patients was determined to be good (weighted kappa = 0.672; P < 0.001). The rate of out-of-phase dating on the day of PO+7 was significantly higher in RIF patients than good prognosis patients (31.6% vs 3.8%, P=0.003).pFET was performed in 47 RIF patients diagnosed to be out of phase, and the accumulative live birth rate was 55.7%.
Conclusions: The endometrial histological dating in RIF patients in natural cycle may be a endometrial receptive biomarker for diagnosing the displacement of WOI.
Spontaneous ovulation versus HCG triggering for timing natural-cycle frozen–thawed embryo transfer: a randomized study
