IMA

1. ENDOMETRIAL RECEPTIVITY
ARRAY
Dr. Gayathiri Ganesan Ram
MS(O.G), Fellow in Reproductive Medicine and
Andrology.
Consultant Reproductive Medicine Specialist
ARC Fertility Hospitals

2. INTRODUCTION
• Implantation is the most crucial stage in
establishment of pregnancy.
• In humans, it has been estimated that
between 30 – 70% of concepts are lost before
or at the time of implantation without women
being aware of having been pregnant.

3. • Successful embryo implantation depends on
interactions between the embryo and the
uterus.

4. • The human endometrium is a highly dynamic
tissue that has the capacity to undergo
physiological changes in response to steroid
hormones, with the ultimate purpose of
creating a receptive status that is synchronized
with the arrival of an implanting blastocyst.

5. DEFINITION
• Implantation is defined as the process by
which an embryo attaches to uterine wall and
first penetrates the epithelium and then
circulatory system forms the placenta.

6. • Human implantation is a highly complex and multifactorial
process.
• Successful implantation at the very least, requires the
presence of a healthy embryo, a receptive endometrium, a
synchronized and successful molecular dialogue between
the two and immune protection from the host.
• Due to lack of objective and accurate methods of
assessment, endometrial receptivity (ER) is rarely
investigated in an infertile patient or even prior to in-vitro
fertilization (IVF).
• Advent of “Omics” that is, the analysis of ‹’••’ŒŠbiological
sampling has revived interest in the study of ER particularly
in the context of implantation failure (IF) in IVF.

18. • The human endometrium is a dynamic tissue; it
undergoes changes at multiple levels during the
menstrual cycle in response to ovarian hormones and
paracrine secretions.
• The endocrine and paracrine secretions control gene
expression of the differentendometrial cell types. The
proliferative phase, controlled by estrogen allows for
the proliferation of stromal cells and glands and
elongation of the spiral arteries. The postovulatory
progesterone (P) rise brings about secretory changes
and the endometrium ŠŒšž’›Žœimplantation of the blastocyst.

19. • During the phase of receptivity, the
endometrium undergoes morphological,
cytoskeletal, biochemical, and genetic changes
to become functionally competent.
• The ability to ’•Ž•’•enhance the outcome of fertility
treatments such as IVF.

20. WOI
• This period of receptivity is known as the
“window of implantation” (WOI). The WOI
opens on day 19 or 20 of the cycle and
remains open for just 4–5 days at the time
when P reaches peak serum concentrations.

22. MARKERS OF ENDOMETRIAL
RECEPTIVITY
• Diagnosis of ER has posed a challenge because of the
lack of an accurate, noninvasive, and clinically
applicable test.
• Histological, biochemical, and ultrasound markers of
ER have been proposed for use to improve
implantation rates (IRs) in IVF.
• Unfortunately, most of these methods are invasive and
none have any predictive value.
• Though limited in value, ultrasound markers of ER are
used in the Œ•’’ŒŠ•value, ultrasound markers of ER are used in
the Œ•’’ŒŠ•clinical settings.

23. HISTOLOGICAL MARKERS
• Endometrial pinopodes identified on electron
microscopy also generated interest as a marker of
ER.
• Pinopods are cytoplasmic projections of the
luminal epithelial cells, abundant during the WOI,
thought to promote blastocyst adhesion.
• The presence of pinopods was demonstrated in
post receptive endometrium, and this precluded
their use as a useful marker of ER.

24. BIOCHEMICAL MARKERS
• A number of molecules present during the mid-
secretory phase have been studied as markers of
ER.
• The ones which have shown significant changes
include ‘ŠŸintegrins, leukemia inhibitory factor,
homeobox A10, mucin 1, calcitonin, and cyclo-
oxygenase 2.
• Many more are being investigated; however,
none have found their ™•ŠŒŽplace in clinical setup.

27. MOLECULAR MARKERS
• The various molecular approaches for the
study of biological samples are collectively
called the “Omics” and include - genomics
(study of genes), epigenomics (study of gene
expression), proteomics (quantification of
proteins), metabolomics and lipidomics
(composition Š•transcriptomics is considered
the most established technology available for
evaluation of the endometrial factor.

28. ERA
• Search for an adequate marker of ER, led to
the development of a molecular diagnostic
test – the endometrial receptivity array (ERA).
ERA consists of a customized microarray based
on the •›ŠœŒ›’™•’Œhuman endometrium is receptive to
blastocyst adhesion.

29. • It has been designed to identify ER by
comparing the •ŽŽ•’Œhormone (LH) + 7 controls in a
natural cycle, or on day 5 of P administration
(P + 5) after E2 priming in a HRT .

32. ERA

35. NATURAL CYCLE
• Biopsy on 7th day after LH surge.
• LH surge is determined in urine/serum once
the follicle has reached 15mm.
• Considering LH surge ad day 0,seven days
must be counted from that day.

36. BIOPSY
• Prepare and label one of the supplied
cryotubes.
• Immediately after the biopsy, introduce the
sample in the cyrotube and shake the sample
vigourouslyfor 10 sec.

37. STORAGE
• Keep in fridge (4 – 8c) for 4 hrs.
• This preserved sample, in cryotube can be
immediately shipped at room temp.
• Sample at room temp should reach the main
lab within 4 to5 days.
• Results will be ready in 20 days after receiving
samples.

39. The accuracy and reproducibility of
the endometrial receptivity array is
superior to histology as a
diagnostic
method for endometrial receptivity
• Patricia Díaz-Gimeno et al, Fertil Steril 2013

40. • Objective: To compare the accuracy and
reproducibility of the endometrial receptivity
array (ERA) versus standard histologic methods.
• Design: A comparative prospective study (May
2008–May 2012).
• Setting: University-affiliated infertility clinic.
• Patient(s): Eighty-six healthy oocyte donors,
regularly cycling, aged 20–34 years with a body
mass index (BMI) of 19–25 kg/m2.

41. • Intervention(s): Endometrial biopsies were collected
throughout the menstrual cycle. For the accuracy
study, 79 samples were grouped into two cohorts: the
training set (n ¼ 79) for ERA machine-learning training
and dating, and a dating subset (n ¼ 49) for
comparison between histologic and ERA dating. For the
reproducibility study, seven women underwent ERA
testing and it was repeated in the same patients on the
same day of their cycle 29–40 months later.
• Main Outcome Measure(s): Concordance of histologic
and ERA dating related to LH as a reference, and
interobserver variability between pathologists were
statistically analyzed by the quadratic weighted Kappa
index.
• The ERA reproducibility was tested and its gene
expression visualized by principal component analysis.

42. • Result(s): For each pathologist, concordance against LH
peak yielded values of 0.618 (0.446–0.791) and 0.685
(0.545–0.824). Interobserver
• variability between pathologists yielded a Kappa index of
0.622 (0.435–0.839). Concordance for ERA dating against
LH peak
• showed a value of 0.922 (0.815–1.000). Reproducibility of
the ERA test was 100% consistent.
• Conclusion(s): The ERA is more accurate than histologic
dating and is a completely reproducible
• method for the diagnosis of endometrial dating and
receptivity status. (Fertil Steril2013;99:508–17. 2013 by
American Society for Reproductive Medicine.)