Comparing pregnancy outcomes using an endometrial receptivity array (ERA) prior to frozen embryo transfer (FET) with euploid embryos

Abstract

Background: The receptivity of the uterus for implantation is determined by a complex interplay of various maternal and embryonic factors. The window of implantation refers to the time period in which a mid-secretory phase endometrium is primed to accept a blastocyst stage embryo. Recent advances in next generation sequencing have allowed for development of tests which can reliably identify the state of the endometrial lining and test for "endometrial receptivity", although their clinical applicability in IVF for improving pregnancy rates has not yet been fully investigated. Objective(s): To compare the effects on pregnancy outcomes in programmed FET cycles in patients who underwent testing with ERA in mock cycles prior to transfer. Material(s) and Method(s): An IRB approved retrospective chart review was performed on 347 patients who had previously had both a mock cycle for an ERA and pre-implantation genetic testing for aneuploidy (PGT-A). The ERA was performed as follows: all patients were treated with 17-beta estradiol (E2) starting on cycle day 1. Blood was drawn on day 3 for E2 to adjust dose. Ultrasound for endometrial thickness and blood test for progesterone (P4) were performed on day 14. If the endometrial lining measured >=7mm and the P4 levels <2ng/ml, patients were started on P4 for luteal support. An endometrial biopsy was performed with an endometrial suction curette pipelle after 4-7 days of P4 supplementation. The ERA was performed by IGENOMIX (Valencia, Spain). Results were graded as receptive, 12-48 hours pre-receptive, or 12-24 hours post-receptive. Patients whose biopsy results were interpreted as receptive underwent FET following the same protocol. Patients who were not receptive had the duration of P4 supplementation prior to FET adjusted based on the results of the ERA. Only patients who had PGT-A confirmed euploid embryos were included for analysis. Groups were compared using chi-squared analysis. Result(s): Two hundred (200) patients were receptive; 47 had failed transfers, 18 had biochemical pregnancies, 18 had miscarriages, 2 had ectopics, and 110 had ongoing pregnancies or live births. 5 were unknown. One hundred forty seven (147) patients were not receptive; 38 had failed transfers, 14 had biochemical pregnancies, 16 had miscarriages, 0 ectopic, and 77 had ongoing pregnancies or live births. 2 were unknown. [Figure presented] Conclusion(s): Our data demonstrates similar pregnancy outcomes between patients that were identified as receptive and patients that were not receptive and had their FET date and duration of P4 adjusted by the results of the ERA. These findings support the validity of the ERA and suggest it may have clinical value in the care of patients undergoing programmed FET cycles with euploid embryos. Financial Support: None Copyright © 2019