Introduction: Endometrial function: facts, urban legends, and an eye to the future

A new method for endometrial dating using computerized virtual pathology

Endometrial dating (ED) is the process by which the menstrual cycle day is estimated and is an important tool for the evaluation of uterine status. To date, ED methods remain inaccurate and controversial. We demonstrate how the rise of computerized virtual histology changes the state of affairs and introduce a new ED method. We present the results of a clinical trial where magnified images of ex-vivo endometrial tissue samples were captured at different cycle days, together with measurements of serum hormone levels on the same day. Patient testimonies about their cycle day were also collected. Computerized image analysis, followed by statistical representation of the tissue features, allowed mathematical representation of the cycle day. The samples underwent ED histological assessment, which is currently the ED gold standard. We compared dating results from patient reports, serum hormone levels, and histology to establish their concordance level. We then compared histology-based ED with the new method ED in the secretory phase (i.e. post ovulation). The correlation coefficient between the two resulted in an R = 0.89 with a P-value of P < 10-4. The new method, Virtual Pathology Endometrial Dating (VPED), has the benefit of being a real time, in-vivo method that can be repeatedly applied without tissue damage, using a dedicated hysteroscope. One practical use of this method may be the determination of accurate real-time embryo transfer timing in IVF treatments.

Endometrial delay is found to be part of a normal individual dynamic transformation process

Purpose

Limited information is clinically available concerning endometrial receptivity; assessing endometrial transformation status is therefore an urgent topic in assisted reproductive technology. This study aimed to investigate individual endometrial transformation rates during the secretory phase in subfertile patients using personal endometrial transformation analysis.

Methods

Monitoring was carried out during the secretory phase to obtain endometrial receptivity profiles. For the investigation, two endometrial biopsies were taken within one menstrual cycle. The extended endometrial dating was based on the Noyes criteria, combined with immunohistochemical analyses of hormone receptors and proliferation marker Ki-67. Biopsies were taken mainly at days ovulation (OV, n = 76)/hormone replacement therapy (HRT, n = 58) + 5 and + 10.

Results

The results of the two biopsies were correlated with the clinically expected day of the cycle and showed temporal delays or hypercompensations, diverging from the expected cycle days by 0.5–5 days. In comparison with the first biopsies, the transformation rate in the second biopsies showed compensation, augmented delay, or constant transformation in 48.69, 22.37, and 28.94% of cases for ovulation in natural cycles and 56.89, 25.85, and 17.26% for HRT cycles, respectively.

Conclusion

The study revealed an individually dynamic transformation process of the endometrium, with the ability to compensate or enlarge an initial “delay”, which is now identified as a normal individual transformation process during the secretory phase. This information is of great importance for the scientific investigation of dynamic changes in endometrial tissue, as well as for the timing of embryo transfers.

Illuminating the "Black Box" of Progesterone-Dependent Embryo Implantation Using Engineered Mice

Synchrony between progesterone-driven endometrial receptivity and the arrival of a euploid blastocyst is essential for embryo implantation, a prerequisite event in the establishment of a successful pregnancy. Advancement of embryo implantation within the uterus also requires stromal fibroblasts of the endometrium to transform into epithelioid decidual cells, a progesterone-dependent cellular transformation process termed decidualization. Although progesterone is indispensable for these cellular processes, the molecular underpinnings are not fully understood. Because human studies are restricted, much of our fundamental understanding of progesterone signaling in endometrial periimplantation biology comes from in vitro and in vivo experimental systems. In this review, we focus on the tremendous progress attained with the use of engineered mouse models together with high throughput genome-scale analysis in disclosing key signals, pathways and networks that are required for normal endometrial responses to progesterone during the periimplantation period. Many molecular mediators and modifiers of the progesterone response are implicated in cross talk signaling between epithelial and stromal cells of the endometrium, an intercellular communication system that is critical for the ordered spatiotemporal control of embryo invasion within the maternal compartment. Accordingly, derailment of these signaling systems is causally linked with infertility, early embryo miscarriage and gestational complications that symptomatically manifest later in pregnancy. Such aberrant progesterone molecular responses also contribute to endometrial pathologies such as endometriosis, endometrial hyperplasia and cancer. Therefore, our review makes the case that further identification and functional analysis of key molecular mediators and modifiers of the endometrial response to progesterone will not only provide much-needed molecular insight into the early endometrial cellular changes that promote pregnancy establishment but lend credible hope for the development of more effective mechanism-based molecular diagnostics and precision therapies in the clinical management of female infertility, subfertility and a subset of gynecological morbidities.

Levonorgestrel IUD: is there a long-lasting effect on return to fertility?

Intrauterine devices (IUDs) are effective and safe long-acting reversible contraceptive methods for preventing unplanned pregnancies. While extensive studies were conducted to evaluate return to fertility after removal of IUDs, majority of them were focused on multiparous women using copper IUDs. Current trends indicate increased use of levonorgestrel (LNG) IUDs in nulliparous women for very long periods of time, with both nulliparity and long duration of LNG-IUD use being potentially associated with trends towards longer time to conception post removal. Understanding the effects that LNG-IUDs may have on endometrial morphology and gene expression has important implications to further understanding their mechanism of action. Studies examining endometrial gene expression show persistent changes in receptivity markers up to 1 year after removal of an inert IUD, and no similar studies have been performed after removal of LNG-IUDs. Given the current gap in the literature and trends in LNG-IUD use in nulliparous young women, studies are needed that specifically look at the interaction of nulliparity, long-term use of LNG-IUD, and return to normal fertility. Herein, we review the available literature on the mechanism of action of IUDs with a specific focus on the effect on endometrial gene expression profile changes associated with IUDs.

Fertility outcome after saline sonography guided removal of intrauterine polyps in women with unexplained infertility

Objective: To assess the effect of removal of unsuspected polyps as delineated on saline sonography on the clinical pregnancy rate in women with unexplained infertility. Methodology: A prospective case control study was being conducted from 1st October 2016 to 30^th September 2018 at Aziz Medical Centre, Karachi. Women diagnosed with unexplained infertility and unsuspected polyps revealed on saline sonography were included as cases (Group A). They were offered removal of polyps under ultrasound guidance and general anesthesia. Saline sonography was repeated at the time to ensure complete removal (Izhar's Modification). Those with unsuspected polyps on saline sonography, but who refused the intervention, were classified as controls (Group B). Both groups were followed for one year. The primary outcome measure was women who had clinical pregnancy i.e. fetal heartbeat present on transvaginal scan during the follow up period. Results: During the study period, out of 92 cases, 37 (40.2%) conceived and out of 92 controls, 10 (10.9%) conceived, which proved that polypectomy increased the chances of conception four-fold (p <0.001). The mean time to conception was also significantly lower for cases than controls (9.26 ± 3.928 months vs. 11.33 ± 2.07 months, p <0.001). The cumulative pregnancy rate was significantly higher in the polypectomy group (log-rank test, p <0.001). The duration of infertility (p = 0.007), position of polyp (p = 0.049) and polypectomy (p <0.001) influenced pregnancy rate. Conclusions: Our study shows the beneficial effect of removal of polyps. Women are four times more likely to conceive spontaneously after polypectomy.

Objective: To assess the effect of removal of unsuspected polyps as delineated on saline sonography on the clinical pregnancy rate in women with unexplained infertility. Methodology: A prospective case control study was being conducted from 1st October 2016 to 30^th September 2018 at Aziz Medical Centre, Karachi. Women diagnosed with unexplained infertility and unsuspected polyps revealed on saline sonography were included as cases (Group A). They were offered removal of polyps under ultrasound guidance and general anesthesia. Saline sonography was repeated at the time to ensure complete removal (Izhar’s Modification). Those with unsuspected polyps on saline sonography, but who refused the intervention, were classified as controls (Group B). Both groups were followed for one year. The primary outcome measure was women who had clinical pregnancy i.e. fetal heartbeat present on transvaginal scan during the follow up period. Results: During the study period, out of 92 cases, 37 (40.2%) conceived and out of 92 controls, 10 (10.9%) conceived, which proved that polypectomy increased the chances of conception four-fold (p <0.001). The mean time to conception was also significantly lower for cases than controls (9.26 ± 3.928 months vs. 11.33 ± 2.07 months, p <0.001). The cumulative pregnancy rate was significantly higher in the polypectomy group (log-rank test, p <0.001). The duration of infertility (p = 0.007), position of polyp (p = 0.049) and polypectomy (p <0.001) influenced pregnancy rate. Conclusions: Our study shows the beneficial effect of removal of polyps. Women are four times more likely to conceive spontaneously after polypectomy.