Assessment of early damage of endometrium after artificial abortion by shear wave elastography

Injectable, degradable, and mechanically adaptive hydrogel induced by L-serine and allyl-functionalized chitosan with platelet-rich plasma for treating intrauterine adhesions

The integration of barrier materials with pharmacological therapy is a promising strategy to treat intrauterine adhesions (IUAs). However, most of these materials are surgically implanted in a fixed shape and incongruence with the natural mechanical properties of the uterus, causing poor adaptability and significant discomfort to the patients. Herein, an injectable, biodegradable, and mechanically adaptive hydrogel loaded with platelet-rich plasma (PRP) is created by L‑serine and allyl functionalized chitosan (ACS) to achieve efficient, comfortable, and minimally invasive treatment of IUAs. L‑serine induces fast gelation and mechanical reinforcement of the hydrogel, while ACS introduces, imparting a good injectability and complaint yet strong feature to the hydrogel. This design enables the hydrogel to adapt to the complex geometry and match the mechanical properties of the uterine. Moreover, the hydrogel exhibits proper degradability, sustained growth factors (GFs) of PRP release ability, and good biocompatibility. Consequently, the hydrogel shows promising therapeutic efficacy by reducing collagen fiber deposition and facilitating endometrium cell proliferation, thereby restoring the fertility function of the uterus in an IUAs model of rats. Accordingly, the combination of L‑serine and ACS-induced hydrogel with such advantages holds great potential for treating IUAs. STATEMENT OF SIGNIFICANCE: This research introduces a breakthrough in the treatment of intrauterine adhesions (IUAs) with an injectable, biodegradable and mechanically adaptive hydrogel using L‑serine and allyl functionalized chitosan (ACS). Unlike traditional surgical treatments, this hydrogel uniquely conforms to the uterus's geometry and mechanical properties, offering a minimally invasive, comfortable, and more effective solution. The hydrogel is designed to release growth factors from platelet-rich plasma (PRP) sustainably, promoting tissue regeneration by enhancing collagen fiber deposition and endometrium cell proliferation. Demonstrated efficacy in a rat model of IUAs indicates its great potential to significantly improve fertility restoration treatments. This advancement represents a significant leap in reproductive medicine, promising to transform IUAs treatment with its innovative approach to achieving efficient, comfortable, and minimally invasive therapy.

Endometrial Elasticity is an Ultrasound Marker for Predicting Clinical Pregnancy Outcomes after Embryo Transfer

Endometrial elasticity is a potential new marker for assessing endometrial receptivity and pregnancy outcomes based on endometrial thickness and type. Currently, little research has been conducted on the elasticity of the endometrium using shear wave elasticity imaging (SWEI). This study aimed to explore whether endometrial elasticity is an ultrasound marker for predicting clinical pregnancy outcomes after embryo transfer. A total of 245 infertile women underwent ultrasonography before embryo transfer at the Peking University Third Hospital. We compared the endometrial elasticity and sub-endometrial blood flow rate using SWEI in the groups with different pregnancy outcomes. Trends in clinical pregnancy outcomes across the quartiles of endometrial elasticity in the fundus of the uterus (E1) were assessed. Logistic regression analysis was performed to obtain odds ratios for clinical pregnancy outcomes based on the quartiles of E1, with or without adjusting for potential confounding variables. Women in the clinical pregnancy group had higher E1 values and sub-endometrial blood flow rates in the uterine fundus than those in the non-pregnancy group. Women in the highest quartile of E1 had the most favorable clinical pregnancy rates. Endometrial elasticity measured using SWEI is a promising ultrasound marker for predicting clinical pregnancy outcomes after embryo transfer.

Evaluation of endometrial receptivity in women with unexplained infertility by shear wave elastography

OBJECTIVES

The endometrium of most unexplained infertility (UI) patients has been altered histologically. Shear wave elastography (SWE) is utilized to assess the signature of living tissue. This study aimed to explore the value of SWE in evaluating endometrial receptivity (ER) in UI patients.

METHODS

In total, 59 UI patients (UI group) and 52 normal control women (NC group) who received fertility consultation in our hospital were included between January 2022 and June 2023. We divided them into the late-proliferative phase of UI group (LPUI; n = 59), mid-secretory phase of UI group (MPUI; n = 41), late-proliferative phase of NC group (LPNC; n = 52), and mid-secretory phase of NC group (MPNC; n = 45). Transvaginal ultrasonography and SWE were performed during the LP and MP. Endometrial thickness (EMT), uterine artery pulsatility index (UA-PI), endometrial mean elasticity (E-mean), and mean shear wave velocities (SWV-mean) were measured.

RESULTS

There were significant differences in E-mean, SWV-mean, EMT, and UA-PI between the UI group and the NC group during both the LP and MP (p MPNC vs MPUI < 0.05, p LPNC vs LPUI < 0.05). E-mean and SWV-mean decreased with increasing EMT but increased with increasing UA-PI (p < 0.05). The most effective parameter for evaluating ER in UI patients is the E-mean (AUC = 0.89).

CONCLUSIONS

UI patients exhibited thinner endometrium, increased endometrial stiffness, and poor endometrial blood perfusion. E-mean was the most effective parameter to evaluate ER in UI patients. The study preliminarily proved that SWE is a promising non-invasive tool for evaluating the condition of endometrium.

CRITICAL RELEVANCE STATEMENT

This study aimed to explore the significance of endometrial elasticity measured by SWE in evaluating patients with UI. The findings revealed a correlation between EMT, UA-PI, and E-mean. Endometrial elasticity can serve as an effective indicator for predicting ER.

KEY POINTS

1. To explore the significance of endometrial elasticity in assessing patients with UI. 2. The endometrium of UI patient exhibited thinness, stiffness, and poor blood perfusion. 3. Endometrial elasticity serves as a valuable indicator for evaluating endometrial receptivity.

Preliminary application of real-time shear wave elastography to evaluate endometrial receptivity and predict pregnancy outcome

BACKGROUND

Endometrial receptivity is crucial for the establishment of a healthy pregnancy outcome. Previous research on endometrial receptivity primarily examined endometrial thickness, endometrial echo types, and endometrial blood supply.

OBJECTIVE

To explore the differences in the elastic modulus of the endometrium in women with various pregnancy outcomes by real-time shear wave elastography (SWE) and to investigate its application value in evaluation of endometrial receptivity.

METHODS

A total of 205 pregnant women who were admitted at Wenzhou People's Hospital between January 2021 and December 2022 were selected. Three-dimensional transvaginal sonography and real-time shear wave elastography were performed in the proliferative phase and receptive phase of the endometrium, and the average elastic modulus of the endometrium in the two phases was obtained and compared. According to whether the pregnancy was successful or not, the participants were divided into the pregnancy group (n= 72) and non-pregnancy group (n= 133), and the differences in intimal thickness, 3D blood flow parameters, and average elastic modulus of intima were compared between the two groups.

RESULTS

The average elastic modulus of the endometrium in the proliferative phase and receptive phase was (23.92 ± 2.31) kPa and (11.82 ± 2.24) kPa, respectively, and the difference was statistically significant P< 0.05. The average elastic modulus of the endometrium in the pregnancy group and non-pregnancy group was (9.97 ± 1.08) kPa and (12.82 ± 2.06) kPa, respectively, and the difference was statistically significant P< 0.05. The area under the curve of predicting pregnancy by the average elastic modulus of the endometrium in the receptive phase was 0.888 (0.841∼0.934), with corresponding P value < 0.05. The critical value was 11.15, with a corresponding sensitivity of 81.7% and specificity of 78.2%.

CONCLUSION

Real-time shear wave elastography can quantitatively evaluate endometrial elasticity, indirectly reflect the endometrial phase, and provide a new diagnostic concept for evaluating endometrial receptivity and predicting pregnancy outcome in infertile patients.

The use of real time strain endometrial elastosonography plus endometrial thickness and vascularization flow index to predict endometrial receptivity in IVF treatments: a pilot study

BACKGROUND

The usefulness of endometrium strain elastosonography (SE) for the evaluation of endometrial receptivity in women undergoing in vitro fertilization (IVF) remains controversial. The objective of this prospective, observational study was to evaluate the correlation between endometrial thickness (EMT) and its related strain (ESR) on the day of ovulation triggering (hCG-d) and in vitro fertilization outcomes. Additionally, 3D Power Doppler vascular indices (3DPDVI) were also analysed.

METHODS

We included all the patients undergoing fresh IVF-single blastocyst transfer cycle from January 2021 to August 2021 at our center. On hCG-d, after B-mode scanning was completed to measure the EMT, the mode was changed to elastosonography to evaluate the ESR (ratio between endometrial tissue and the myometrium below). At the end of examination, the Endometrial Volume (EV) and 3DPDVI (vascularization index [VI], flow index [FI] and vascularization flow index [VFI]), were assessed. Statistical analysis was completed using STATA MP16 software.

RESULTS

A total number of 57 women were included. Based on the EMT on hCG-d, women were divided into two groups, Group 1: <7 mm and Group 2 ≥ 7 mm. Women with EMT < 7 mm had a significantly higher ESR (p = 0.004) and lower pregnancy rate (p = 0.04). Additionally, low ESR values were correlated with high VFI values (rho = -0.8; 95% CI = -0.9- -0.6; p < 0.0001) and EMT ≥ 7 mm could be predicted by low ESR (OR = 0.01; 95% CI = 0.01-0.30; p = 0.008, area under the ROC curve: 0.70). After all, in multiple logistic regression analysis, low values of ESR (p = 0.050) and high values of EMT (p = 0.051) on hCG-d had borderline statistical effects on pregnancy rate.

CONCLUSIONS

The ESR may be useful to improve the ultrasound evaluation of the endometrial quality in infertile women candidates to IVF/ICS. Given the small sample size of our study, the usefulness of strain elastosonography in this patients, needs further investigation.

Development of a Nomogram for Predicting Intravasation Before Transvaginal 4-Dimensional Hysterosalpingo-Contrast Sonography

Background

Intravasation during transvaginal 4-dimensional hysterosalpingo-contrast sonography (TVS 4D-HyCoSy) may lead to false-negative results in tubal patency evaluation. Although the influencing factors associated with intravasation have been investigated, some factors are only identified during 4D-HyCoSy, thus currently no studies on preventing intravasation. However, several preprocedural features can be collected in advance, which may be valuable in predicting intravasation.

Objective

The purpose of this study is to establish a nomogram incorporating the preprocedural features to predict the risk of intravasation before TVS 4D-HyCoSy.

Methods

The data of 276 infertile women with patent fallopian tubes were analyzed retrospectively. They were assigned to the study group (n = 62) and the control group (n = 214) according to the development of intravasation. The preprocedural characteristics were collected to investigate the predictors independently associated with intravasation, which were then served as the construction of a nomogram. The performance of the nomogram was verified internally.

Results

History of uterine curettage (OR = 2.341, P = 0.009), endometrial thickness (OR = 0.587, P < 0.001), and examination schedule (OR = 0.790, P = 0.024) were found to be the independent influencing factors associated with intravasation. The established nomogram incorporating these preprocedural features was useful for predicting the risk of intravasation prior to 4D-HyCoSy. It yielded net benefits when the predicted probability was less than 50%.

Conclusion

The nomogram incorporating the preprocedural characteristics achieved a net benefit for clinical decision-making when the estimated risk was less than 50%. It is recommended to change the examination schedule for patients with an estimated risk greater than 50% and perform 4D-HyCoSy when the risk is less than 50%.

3D stem cell-laden artificial endometrium: successful endometrial regeneration and pregnancy

Thin endometrium lining or severe endometrial injury which may occur during artificial abortion can cause defective endometrial receptivity and subsequent infertility. Therefore, much effort has been devoted toward regenerating thin or damaged endometrial lining by applying multiple types of stem cells. Even though there are some positive preliminary outcomes, repairing the injured endometrium with stem cells is considerably challenging, due to the lack of an adequate microenvironment for the administrated stem cells within the tissues and subsequent poor therapeutic efficiency. In this context, as an alternative, we fabricated a 3D stem cell-laden artificial endometrium by incorporating several biodegradable biomaterials (collagen and hyaluronic acid) and multiple cellular components of endometrium (endometrial stem cells, stromal cells, and vessel cells) to properly recapitulate the multicellular microenvironment and multilayered structure. Agarose was used as an inert filler substrate to enhance the mechanical integrity of the three-layered artificial endometrium. Various mechanical characteristics, such as morphology, compression properties, swelling, and viscosity, have been evaluated. Various biological features, such as steroid hormone responsiveness, specific endometrial cell-surface marker expressions, and the secretion of multiple growth factors and steroid hormones, as well as the viability of encapsulated endometrial cells are relatively well maintained within the artificial endometrium. More importantly, severe tissue injuries were significantly relieved by transplanting our 3D artificial endometrium into endometrial ablation mice. Remarkably, artificial endometrium transplantation resulted in a successful pregnancy with subsequent live birth without any morphological or chromosomal abnormalities.

Development of a novel dual reproductive organ on a chip: recapitulating bidirectional endocrine crosstalk between the uterine endometrium and the ovary

Conventional 2D or even 3Din vitroculture models for human reproductive organs cannot properly recapitulate the bidirectional endocrine crosstalk between the uterine endometrium and the ovary. This crosstalk is essential for maintaining the various physiological features and functions of each tissue. Moreover, mostin vitromodels for the female reproductive tract also fail to mimic its multicellular structure. We therefore developed a novel 'dual reproductive organ on a chip' that reflects the bidirectional endocrine cross-talk and the complex multicellular structures by integrating various cellular components of both the human uterine endometrium and the ovary with several biodegradable natural polymers. Indeed, the bidirectional endocrine crosstalk between these two tissues is achieved through media sharing between channels, and it can markedly improve the viability of loaded cells within each chamber of the chip platform. In addition, we also identified a reliable reproductive toxicity marker, SERPINB2, which is significantly increased in response to various toxic exposures in both endometrial and ovarian follicular cells. Based on these findings, we next established a SERPINB2 luciferase reporter system that was specifically designed for detecting and quantifying the toxicity of certain substances. By introducing this SERPINB2 luciferase reporter system into the loaded cells within the chip platform, we ultimately developed an effective 'dual reproductive organ-on-chip' that was successfully used to predict the reproductive toxicity of various hazardous materials.