The thin endometrium in assisted reproductive technology: An ongoing challenge

Impaired receptivity of thin endometrium: therapeutic potential of mesenchymal stem cells

The endometrium is a resilient and highly dynamic tissue, undergoing cyclic renewal in preparation for embryo implantation. Cyclic endometrial regeneration depends on the intact function of several cell types, including parenchymal, endothelial, and immune cells, as well as adult stem cells that can arise from endometrial or extrauterine sources. The ability of the endometrium to undergo rapid, repeated regeneration without scarring is unique to this tissue. However, if this tissue renewal process is disrupted or dysfunctional, women may present clinically with infertility due to endometrial scarring or persistent atrophic/thin endometrium. Such disorders are rate-limiting in the treatment of female infertility and in the success of in vitro fertilization because of a dearth of treatment options specifically targeting the endometrium. A growing number of studies have explored the potential of adult stem cells, including mesenchymal stem cells (MSCs), to treat women with disorders of endometrial regeneration. MSCs are multipotent adult stem cells with capacity to differentiate into cells such as adipocytes, chondrocytes, and osteoblasts. In addition to their differentiation capacity, MSCs migrate toward injured sites where they secrete bioactive factors (e.g. cytokines, chemokines, growth factors, proteins and extracellular vesicles) to aid in tissue repair. These factors modulate biological processes critical for tissue regeneration, such as angiogenesis, cell migration and immunomodulation. The MSC secretome has therefore attracted significant attention for its therapeutic potential. In the uterus, studies utilizing rodent models and limited human trials have shown a potential benefit of MSCs and the MSC secretome in treatment of endometrial infertility. This review will explore the potential of MSCs to treat women with impaired endometrial receptivity due to a thin endometrium or endometrial scarring. We will provide context supporting leveraging MSCs for this purpose by including a review of mechanisms by which the MSC secretome promotes regeneration and repair of nonreproductive tissues.

Intrauterine instillation of autologous platelet-rich plasma in infertile females with thin endometrium undergoing intrauterine insemination: an open-label randomized controlled trial

BACKGROUND

Thin endometrium in infertile female patients has always been a clinical challenge for the treating reproductive physicians.

OBJECTIVE

This study aimed to evaluate the effect of intrauterine instillation of autologous platelet-rich plasma on endometrial thickness and vascularity in infertile female patients with thin endometrium undergoing ovarian stimulation with intrauterine insemination.

STUDY DESIGN

This prospective randomized control study included 120 women undergoing ovarian stimulation with intrauterine insemination, aged between 21 and 37 years, with persistent thin endometrium (<7 mm) on ≥1 cycle in previous ovarian stimulation cycles, even after conventional treatment with estradiol valerate. The women were randomly assigned to study group A and control group B. Baseline endometrial thickness and endometrial vascularity were noted. Intrauterine instillation of autologous platelet-rich plasma was done on the day of trigger in group A, whereas estradiol valerate was given in group B. Another evaluation of endometrial parameters was done on the day of intrauterine insemination. The cycle was repeated for 3 cycles or until the pregnancy was achieved, whichever occurred earlier. Parameters were noted for both groups. Primary outcomes were the change in endometrial thickness and endometrial vascularity. Secondary outcomes were positive pregnancy rate and clinical pregnancy rate.

RESULTS

In group A, mean pre-platelet-rich plasma endometrial thickness was 4.66±0.79 mm, which significantly increased to 7.47±0.85 mm after platelet-rich plasma instillation (P<.05) after 3 cycles. This increase was significantly greater than that observed in group B. There was significant increase in endometrial vascularity in group A compared with group B (P<.05). The positive pregnancy rate and clinical pregnancy rate in group A were 23.73% and 18.64%, respectively, and significantly higher than those in group B.

CONCLUSION

Autologous platelet-rich plasma is a promising, easily procurable, and novel option for management of infertile females with thin endometrium not responding to conventional treatment. Using it in intrauterine insemination cycles can reduce costs and psychological burden of this subgroup of women by reducing the need for resorting to advanced options such as in vitro fertilization and surrogacy.

Spider diagram and sustainability evaluation of UV-methods strategy for quantification of aspirin and sildenafil citrate in the presence of salicylic acid in their bulk and formulation

The cutting-edge combination of aspirin (ASA) and sildenafil citrate (SIC) has been presented as a suggested dosage form for the treatment of thin endometrium and erectile dysfunction, particularly in patients with cardiovascular diseases. However, ASA is highly sensitive to degradation into its major deterioration product, known as salicylic acid (SA). Consequently, it is eminently essential to evolve approaches for the synchronous quantification of ASA and SIC in the presence of SA. The main objective of this work is to develop three approaches for the synchronous quantification of ASA and SIC in the presence of SA in their commixtures and suggested formulations without any prior separation. Three green UV-methods were employed for the synchronous quantification, namely: Dual Wavelength in Ratio Spectra (DW-RS), Advanced Amplitude Centering (AAC), and Double Divisor of Ratio Difference Derivative (DDRD-D₁). In DW-RS and AAC two-wavelength manipulation was used for resolution, while in DDRD-D₁ only an appropriate wavelength for the synchronous quantification of the triplex commixture was used. All approaches can be able to resolve the highly interfering spectrum of the three components presented in the triplex commixture. Good linearity was inspected in the range of 20.0-100.0, 5.0-50.0, and 4.0-60.0 μg/mL for the ASA, SIC, and SA, respectively. All developed approaches have been advocated in accordance with ICH guidelines. All results from these approaches are presented and statistically reconciled with the proclaimed HPLC method, with no considerable differences. Furthermore, the approaches' eco-friendliness was predestined by Analytical Greenness (AGREE), and the complex GAPI. Moreover, the sustainability of the used solvent was evaluated by Green Solvents Selecting Tool (GSST); in addition, the greenness of the solvent was evaluated by Greenness Index tool with a spider diagram. The suggested UV-methods may be employed for routine quality control studies of the suggested formulations ASA & SIC since they were considered sustainable, economical, and effective.

Cell-based endometrial regeneration: current status and future perspectives

Endometrial-related disorders including Asherman's syndrome, thin endometrium, pelvic organ prolapse, and cesarean scar pregnancies can be accompanied by different symptoms such as amenorrhea, infertility, abnormal placental implantation and recurrent miscarriage. Different methods have been introduced to overcome these problems such as surgery and hormonal therapy but none of them has shown promising outcomes. On the other hand, the development of novel regenerative therapeutic strategies has opened new avenues for the treatment of endometrial-related deficiencies. In this regard, different types of scaffolds, acellular matrices and also cell therapy with adult or stem cells have been investigated for the treatment of endometrial-related deficiencies. In this paper, we review the current status of cell-based endometrium regeneration using scaffold dependent and scaffold-free methods and future perspectives in this field. Moreover, we discuss the endometrial diseases that can be candidates for cell-based treatments. Also, the cells with the potential for endometrial regeneration are explained.

The correlation between endometrial thickness and pregnancy outcomes in fresh ART cycles with different age groups: a retrospective study

Background

In assisted reproductive technology (ART) cycles in addition to embryo quality, the receptivity of the endometrium plays the main role in clinical outcomes. Endometrial receptivity is necessary to implantation of an embryo, and ultrasound has been established as an appreciated, simple, and non-invasive technique in the evaluation of the endometrial preparation before embryo transfer in fresh in vitro fertilization (IVF) cycles. Debate on the predictive value measuring endometrial thickness before administering human chorionic gonadotropin (HCG) for ovulation triggering in ART is ongoing. In order to explore the impact of endometrial thickness on triggering day on ongoing pregnancy rate (OPR) in ART cycles, we retrospectively analyzed data from 1000 patients undergoing IVF/ICSI cycles.

Results

The data showed pregnancy rate was increased in the endometrial thickness of 8 mm to 11 mm then decreased, and in endometrial thickness (Ent) > 14 mm, pregnancy rate was zero. There were significant differences in endometrial thickness and pregnancy outcomes between different age groups. The pregnancy rate was higher (32%) in 23–30 years old women, and the range of Ent in this group was 6–12 mm. Also, the data showed a positive correlation between Ent with AMH and estradiol levels and the number of COC and MII oocytes and a negative correlation between female age with Ent.

Conclusion

The result showed that Ent on hCG administration day is associated with pregnancy outcomes in fresh IVF/ICSI cycles with different age groups, although some of the clinical parameters may have an effect on Ent. Large studies are needed to make a definitive conclusion.

Protective effect of green tea on tunica adventitia and endothelial changes resulting from depot medroxy progesterone acetate

Objective

This study aimed to analyse the effects of green tea in inhibiting uterine atrophy and vascular changes due to the use of depot medroxy progesterone acetate (DMPA).

Methods

Twenty-five female Wistar rats aged one to two months were randomly assigned to five treatment groups: control group, DMPA-induced group, and DMPA-induced group orally treated with green tea extract (at 10.8 mg/day, 21.6 mg/day, or 43.2 mg/day). Histologic analysis of uterine and vascular tissues was performed with haematoxylin-eosin staining.

Results

DMPA decreased the thickness of endometrium and tunica adventitia, as well as significantly decreased endothelial cell count (p < 0.05). DMPA-induced decreases in the thickness of tunica adventitia and endothelial cell count could be significantly inhibited by green tea extract (p < 0.05).

Conclusion

This study concluded that DMPA triggered the depletion of uterine endometrium and vascular tunica adventitia and decreased endothelial cell count. Green tea extract at the highest dose normalized tunica adventitia and endothelial changes to the basal value.