Improvement Of Endometrial Receptivity Research Articles

Shoutai Pill Enhances Endometrial Receptivity in Controlled Ovarian Hyperstimulation Mice by Improving the In-Vivo Immune Environment.

The Shoutai pill (STP) is a classic formulation in traditional Chinese medicine. Preliminary experimental observations from our study suggest that it is effective in enhancing endometrial receptivity. However, the underlying mechanisms by which STP influences endometrial receptivity remain to be elucidated. The objective of this study is to investigate the effects and mechanisms of the STP formulation in enhancing endometrial receptivity in controlled ovarian hyperstimulation (COH) model mice. The network pharmacology analysis identified target proteins associated with the reduction of endometrial receptivity by STP. The COH mouse model was established using the GnRHa+PMSG+HCG protocol. The levels of MHC-1 and MHC-2 in mouse serum were measured using the ELISA method, while the levels of IL-1B, IL-4, IL-10, IP-10, IL-1a, IL-2, IL-17, TNF-a, and IFN-y were measured using liquid chip technology. STP exhibited a significant improvement in the immune environment of COH model mice. The major active components of STP were identified as beta-sitosterol and quercetin, among others. Furthermore, AKT1, VEGFA, and several immune factors, such as TNF, IFN, IL1B, and IL10, were identified as key targets for regulating endometrial receptivity. STP enhanced the expression of IL-10, IL-4, and IP-10 in the mice while reducing the expression levels of IL-2, IL-17, TNF-α, and IFN-γ in COH mice. These effects led to the modulation of early high expression of IL-1B and an improvement in endometrial receptivity. This study demonstrates that STP can modulate in-vivo immune factors throughout the COH process, subsequently restoring the immune equilibrium within the endometrium, thereby enhancing the endometrial receptivity in the COH model mice.

Ligustilide enhances pregnancy outcomes via improvement of endometrial receptivity and promotion of endometrial angiogenesis in rats.

Ligustilide (LIG) is the main active ingredient of Angelica sinensis (Oliv.) Diels, which could promote focal angiogenesis to exert neuroprotection. However, there was no report that verified the exact effects of LIG on endometrial angiogenesis and the pregnancy outcomes. To explore the effects of LIG on low endometrial receptivity (LER) and angiogenesis, pregnancy rats were assigned into Control (saline treatment), LER (hydroxyurea-adrenaline treatment), LIG 20mg/kg and LIG 40mg/kg groups. Hematoxylin and eosin (H&E) staining was performed to evaluate endometrial morphology. Quantitative real-time PCR, immunofluorescence staining, western blot and immunohistochemistry staining were employed to assess the expression of endometrial receptivity factors and angiogenesis-related gene/protein, respectively. RNA sequencing was used to analyze the effects of LIG on LER caused by Kidney deficiency and blood stasis. We found that endometrial thickness and the implanted embryo number were substantially reduced in the hydroxyurea-adrenaline-treated pregnancy rats. At the same time, the gene and protein expressions of ERα, LIF, VEGFA and CD31 in the endometrium were markedly reduced, while the expressions of MUC1, E-cadherin were increased in the LER group. Administration of LIG raised the endometrial thickness and implanted embryos, as well as reversed the expressions of these factors. Collectively, our findings revealed that LIG could facilitate embryo implantation via recovery of the endometrium receptivity and promotion of endometrial angiogenesis.

Tiaojing Cuyun Recipe Enhances Pregnancy Outcome via the VEGF/PI3K/AKT/eNOS Signaling Pathway in EID Mice.

Purpose In this study, we evaluated the effect of Tiaojing Cuyun Recipe (TJCYR) on embryo implantation dysfunction- (EID-) induced damage of endometrial receptivity in mice and investigated the mechanisms underlying the effect. Methods The main compounds of TJCYR were identified by high-performance liquid chromatography (HPLC). One hundred and twenty pregnant mice were randomly divided into six groups: control, EID only, progesterone (Prog)+EID, TJCYR-low-dose+EID, TJCYR-medium-dose+EID, and TJCYR-high-dose+EID. Mifepristone was injected to make the EID model. On the fourth day of pregnancy, serum was obtained to analyze hormone level by radioimmunoassay, the uterus was collected to analyze morphology by hematoxylin and eosin (H&E) and scanning electron microscopy (SEM), and a combination of immunofluorescence and Western blot was used to identify the related proteins. On the eighth day of pregnancy, the mice were sacrificed and the number of uterus-implanted blastocysts was counted. Results Treatment with TJCYR significantly improved the number of implanted sites, the number of well-developed pinopodes, and microvascular formation in the mice. Moreover, TJCYR significantly activated PI3K/Akt/eNOS signaling pathways to promote angiogenesis, resulting in significantly improved endometrial receptivity and fertility outcomes when compared to the model group. Conclusion These findings demonstrate that TJCYR was able to protect embryo implantation of EID mice due to TJCYR-mediated improvement in endometrial receptivity by promoting endometrial angiogenesis.

Transcriptome analysis of eutopic endometrium in adenomyosis after GnRH agonist treatment

BackgroundAdenomyosis is a chronic gynecological disease characterized by invasion of the uterine endometrium into the muscle layer. In assisted reproductive technology (ART), gonadotropin-releasing hormone agonist (GnRHa) is often used to improve pregnancy rates in patients with adenomyosis, but the underlying mechanisms are poorly understood.MethodsEutopic endometrial specimens were collected from patients with adenomyosis before and after GnRHa treatment in the midsecretory phase. RNA sequencing (RNA-Seq) of these specimens was performed for transcriptome analysis. The differentially expressed genes (DEGs) of interest were confirmed by real-time PCR and immunohistochemistry.ResultsA total of 132 DEGs were identified in the endometrium of patients with adenomyosis after GnRHa treatment compared with the control group. Bioinformatics analysis predicted that immune system-associated signal transduction changed significantly after GnRHa treatment. Chemokine (C-C motif) ligand 21 (CCL21) was found to be highly expressed in the eutopic endometrium after GnRHa treatment, which may be involved in the improvement of endometrial receptivity in adenomyosis.ConclusionThis study suggests that molecular regulation related to immune system-associated signal transduction is an important mechanism of GnRHa treatment in adenomyosis. Immunoreactive CCL21 is thought to regulate inflammatory events and participate in endometrial receptivity in adenomyosis.

Evaluation the effect of sildenafil on nitric oxide secretion and improvement of endometrial receptivity in fresh ICSI cycles

Introduction: Endometrial receptivity is a chain of events that promotes embryo implantation and is regulated by a variety of substances, such as cytokines, growth factors, and steroid hormones. The study's objective is to assess how vaginally delivered sildenafil in ICSI patients affects pregnancy outcome, endometrial thickness, subendometrial resistance index, and pulsatility index. Methods: The sixty women who participated in this controlled randomised trial (interventional experimental research) at the High Institute of Infertility Diagnosis and Assisted Reproductive Technologies underwent IVF/ICSI cycles. Patients were split into two groups: Study group: From the day of the last menstrual period to the day of the hCG injection, thirty (30) infertile women got four (4) doses of vaginal sildenafil 25mg tablets daily. Thirty (30) infertile ladies who weren't given sildenafil therapy made up the control group. Results: Nitric oxide levels in the study group's serum were significantly significant. In the subendometrial Doppler research, the mean pulsatility index was considerably lower in the study group whereas the mean resistance index and mean systolic to diastolic ratio did not change statistically between the control and study groups. Between the control and study groups, there was no statistically significant difference in the mean endometrial thickness. The sildenafil group had a greater pregnancy rate, although the difference was not statistically significant. Conclusion: By enhancing subendometrial blood flow by lowering the pulsatility index and raising the nitric oxide (NO) factor, the use of vaginal sildenafil in a new ICSI cycle improves endometrial receptivity.

A CLINICAL STUDY TO EVALUATE THE EFFICACY OF GUDUCHYADI TAILA MATRABASTI IN VANDHYATWA W.S.R. TO ENDOMETRIAL RECEPTIVITY

Infertility is a public health issue in India and many other developing countries because of its high prevalence and especially due to its serious social implications. According to the data of WHO, more than 180 million couples in developing countries agonise from primary or secondary infertility. The social stigma of childlessness still leads to isolation and abandonment in many communities. Although there is a lot of advancement in infertility care, the availability, affordability and effectiveness are still very low. Ayurveda described the disease vandhyatwa as equivalent to infertility. In Ayurveda, the management of Vandhyatwa mainly focuses on the correction of garbha sambahava samagris. Kshetra which is one among them is considered as the prime factor for conception. Kshet- ra can be taken as the female reproductive system, a well-prepared endometrium for implantation. Optimal en- dometrial receptivity leads to proper implantation of the embryo, which is the foundation of a healthy pregnancy. Implantation failure due to reduced endometrial receptivity is one of the major causes of infertility. In this present study, the endometrial receptivity was assessed with Applebaum's uterine score and Guduchyadi taila matrabasti has been administered to increase the receptivity of the endometrium. After the intervention, the results obtained showed significant improvement in endometrial receptivity. Keywords: Vandhyatwa, Applebaum's scoring, Matrabasti, Guduchyadi taila

CXCL12 enhances pregnancy outcome via improvement of endometrial receptivity in mice

Successful pregnancy inevitably depends on the implantation of a competent embryo into a receptive endometrium. Although many substances have been suggested to improve the rate of embryo implantation targeting enhancement of endometrial receptivity, currently there rarely are effective evidence-based treatments to prevent or cure this condition. Here we strongly suggest minimally-invasive intra-uterine administration of embryo-secreted chemokine CXCL12 as an effective therapeutic intervention. Chemokine CXCL12 derived from pre- and peri-implanting embryos significantly enhances the rates of embryo attachment and promoted endothelial vessel formation and sprouting in vitro. Consistently, intra-uterine CXCL12 administration in C57BL/6 mice improved endometrial receptivity showing increased integrin β3 and its ligand osteopontin, and induced endometrial angiogenesis displaying increased numbers of vessel formation near the lining of endometrial epithelial layer with higher CD31 and CD34 expression. Furthermore, intra-uterine CXCL12 application dramatically promoted the rates of embryo implantation with no morphologically retarded embryos. Thus, our present study provides a novel evidence that improved uterine endometrial receptivity and enhanced angiogenesis induced by embryo-derived chemokine CXCL12 may aid to develop a minimally-invasive therapeutic strategy for clinical treatment or supplement for the patients with repeated implantation failure with less risk.

The Lipiodol Uterine Bathing Effect to Improve Fertility May Include Uterine Natural Killer Cell Up-regulation in the Endometrium

BACKGROUND: Lipiodol has a dramatic short term fertility enhancing effect for women with endometriosis. Microarray studies have shown transcriptomic regulation of molecular markers of endometrial inflammation, most notably a consistent down-regulation of endometrial osteopontin. We further explored the endometrial bathing effect of lipiodol on leukocyte expression in endometrium. METHODS: A cohort of four women, nested within a randomised trial of twelve women assessing the lipiodol uterine bathing effect, was studied as an ‘own control’ group, with their mid-luteal endometrium assessed before and after endometrial lipiodol exposure. Pipelle endometrial sampling allowed endometrial assessment by immunochemistry. Endometrial tissue samples were assessed by immunochemistry for total CD45+ leukocytes, CD68+ macrophages, CD3+ T-cells and CD56+ uterine natural killer cells. RESULTS: There was a statistically significant increase in the mean density of uterine natural killer cells in the endometrium of women post-lipiodol. No other significant differences were found in the mean densities of all leukocytes, macrophages or T cells in the endometrium of women post-lipiodol. CONCLUSIONS: These preliminary data further support the concept of a uterine bathing effect of lipiodol. Whether the increase in the mean density of uterine natural killer cells in the endometrium might contribute to an improvement in endometrial receptivity to embryo implantation merits further investigation.

PRP-THERAPY OF ENDOMETRIUM: THE LATEST METHODS IN THE FIELD OF ASSISTED REPRODUCTIVE TECHNOLOGIES

Recently, the preparation of the endometrium for embryo transfer, namely the achievement of optimal thickness and receptivity of the endometrium, the prevention of unsuccessful attempts to implant embryos, is gaining more and more attention among doctors in the field of reproductive medicine. Since cryptocycles of embryo transfer preparation are often discontinued in the practice of a reproductive physician due to insufficient endometrial thickness, high doses of estrogen and negative IVF results provided the satisfactory condition of the endometrium on the day of transfer and quality of the embryos. The article briefly presents the views on the effectiveness of PRP therapy of the endometrium in the protocols of preparation for embryo transfer. The main mechanisms of the effect of platelet-rich blood plasma on the endometrium are elucidated. The positive effect of this technique on regeneration, increase in thickness and improvement of endometrial receptivity is proved.
 Conclusion. PRP-therapy of the endometrium is a modern, affordable, effective and safe method of treatment of thin and damaged endometrium in reproductive medicine.

Alleviation of Symptoms and Improvement of Endometrial Receptivity Following Laparoscopic Adenomyoma Excision and Secondary Therapy with the Levonorgestrel-releasing Intrauterine System.

To assess the treatment efficacy of adenomyoma and improvement in implantation receptivity associated with the levonorgestrel-releasing intrauterine system (LNG-IUS) combined with adenomyoma resection. Fifty subjects (control group) underwent laparoscopic adenomyoma excision and received gonadotropin-releasing hormone (GnRH) agonists, and 201 subjects (experimental group) underwent laparoscopic adenomyoma resection and received GnRH agonists combined with the LNG-IUS. Pipelle endometrial biopsies were obtained in the mid-luteal phase, before the operation, and 19months after the operation. Menstrual blood loss was measured using a pictorial blood loss assessment chart. Pain intensity during menstruation was evaluated on a 10-point visual analog scale (VAS). The volume of uterus was measured through ultrasound. Quantification of HOXA10 promoter methylation was performed through bisulfite sequencing polymerase chain reaction (BSP). Real-time polymerase chain reaction analyzed the expression levels of endometrial HOXA10-mRNA and leukemia inhibitory factor (LIF)-mRNA. After surgery, the scores for dysmenorrhea and menorrhagia were significantly improved, and the volume of the uterus was obviously reduced (all p < 0.01). The mean number of methylated CpG sites, level of endometrial HOXA10-mRNA, and level of endometrial LIF-mRNA were 5.6 ± 1.7 versus 3.9 ± 1.3, 0.8 ± 0.2 versus 0.9 ± 0.3, and 0.8 ± 0.2 versus 1.0 ± 0.2, respectively, in the control group versus the experimental group at 19months after surgery, and significant improvements were observed in the experimental group (p < 0.001, p = 0.034, p < 0.001). Laparoscopic adenomyoma excision and GnRH agonists can alleviate the symptoms, reduce the number of methylated CpG sites in HOXA10, and improve endometrial HOXA10-mRNA and endometrial LIF-mRNA levels. When combined with subsequent use of the LNG-IUS, better efficacy can be achieved.

The role played by granulocyte colony stimulating factor (G-CSF) on women submitted to in vitro fertilization associated with thin endometrium: systematic review.

Objective:To provide evidence available in the literature on the role of granulocyte colony stimulating factor (G-CSF) in women submitted to in vitro fertilization, with repeated implantation failure associated with thin endometrium.Methods:Systematic review of the use of G-CSF, as part of assisted reproduction techniques in women with repeated embryo implantation failures associated with thin endometrium. The study was carried out in the PubMed, BIREME and Elsevier databases from 2008 to 2018, in English, Spanish and Portuguese.Results:We included all the studies, which used intrauterine G-CSF. We found an increase in endometrial thickness in eight of the 10 studies included. Of these, the implantation rate improved significantly in two studies, but the gestation rate increased in only one. We found the highest rates of implantation (32%) and pregnancy (48%) in a non-randomized clinical trial. On the other hand, two other studies did not demonstrate an increase in endometrial thickness and in pregnancy rates in patients with thin endometrium submitted to the assisted reproduction in frozen embryo transfer cycles.Conclusion:Studies published so far point to a positive influence on the use of G-CSF in relation to the improvement in endometrial receptivity and pregnancy rates. Therefore, there is a need for further studies to determine whether to use it, as well as the period, route of administration, dosage and duration of treatment.

Миомэктомия: рациональное ведение периоперационного периода и отдаленные результаты лечения

Objective – to study the influence of various surgical approaches on the outcomes of myomectomy and to determine the optimal strategy of postoperative management of patients of childbearing age with uterine fibroids. Patients and methods. A retrospective study included 145 patients who had uterine fibroids with a total increase of 480–560 cm3, with the intramural component not less than 55% of the total volume. Patients of group 1 (n = 62) underwent classical laparoscopic myomectomy. Patients of group 2 (n = 48) had surgery supplemented by temporary reduction of arterial perfusion by temporary clipping of the uterine or internal iliac arteries. Robot-assisted myomectomy was performed in 34 patients of group 3. The comparison group comprised 54 women with uterine fibroids of the same sizes who did not undergo operative treatment, and the control group consisted of 36 healthy women. Results. After myomectomy, the progesterone/oestradiol receptor ratio in the endometrium increased from 1.8 to 4.6 and from 1.6 to 2.7 in patients who suffered from primary or secondary infertility before surgery. After surgery, the expression of НОХА-10 became higher in the epithelium and pinopodes of patients of both groups. But the positive response of the stromal cells was obtained only in women who had pregnancies before surgery. The expression of the proto-oncogene bcl-2 after myomectomy decreased in patients of all groups in both the stroma and epithelium, but it was more pronounced in women with primary infertility. Changes in the endometrium occur irrespective of the type of operative intervention. Taking into account the fact that temporary cessation of arterial perfusion in the uterus does not worsen endometrial receptivity but allows a 5-fold reduction of intraoperative blood loss, this technique might be regarded as one of the most effective for prevention of intra- and postoperative complications. The incidence of pregnancy following myomectomy was 84.7% among women who planned conception, whereas among women with myoma it was only 18.9%. The number of pregnancies after assisted reproductive technologies amounted to 19.4% of the total number of patients. Conclusion. Surgical treatment of uterine fibroids makes it possible to improve a reproductive prognosis and achieve a pregnancy in 85% of cases, which, among other factors, is due to improvement of endometrial receptivity. Key words: pregnancy, contraception, uterine fibroid, myomectomy, reproductive outcomes, endometrial receptivity

Bu Shen Zhu Yun Decoction Improves Endometrial Receptivity via VEGFR-2-Mediated Angiogenesis.

Vascular endothelial growth factor receptor-2 (VEGFR-2) regulates the mitogen-activated protein kinase (MAPK) signaling pathway and plays an important role in angiogenesis. Bu Shen Zhu Yun decoction (BSZYD) can improve endometrial receptivity and embryo implantation rates in patients undergoing in vitro fertilization. However, whether BSZYD improves endometrial receptivity via angiogenesis remains unclear. Here, we investigated the effects of BSZYD on the proliferation, migration, and angiogenesis of human endometrial microvascular endothelial cells (HEMECs) and found that BSZYD upregulated the expression of cyclin D1, matrix metalloproteinase 9 (MMP9), and proliferating cell nuclear antigen (PCNA) in HEMECs. Cell Counting Kit 8 assay, scratch-wound assay, and Tube Formation Assay results showed that BSZYD promoted the proliferation, migration, and angiogenesis of HEMECs. Western blot analysis results revealed the activation of the MAPK signaling pathway by BSZYD through the upregulation of VEGF and VEGFR-2 expression. Together, these findings highlight the novel mechanism underlying BSZYD-mediated improvement in endometrial receptivity through the MAPK signaling pathway.

Enhancement of Endometrial Receptivity by Cnidium officinale through Expressing LIF and Integrins.

Improvement of endometrial receptivity is necessary for successful embryo implantation, and its impairment is associated with female infertility. In this study, we investigated the effect of the roots of Cnidium officinale Makino (CoM) on endometrial receptivity in both in vitro and in vivo model of embryo implantation. We found that CoM enhanced the adhesion of JAr cells to Ishikawa cells by stimulating expression of leukemia inhibitory factor (LIF) and integrins. In addition, blocking of LIFR using hLA or neutralization of integrins αV, β3, and β5 using antibodies significantly reduced the enhanced adhesion between JAr cell and CoM-treated Ishikawa cells, indicating that LIF and integrin play an important role in trophoblast-endometrium adhesion for embryo implantation. Furthermore, we identified that CoM significantly improved the implantation rate of blastocysts in the mouse model of RU-induced implantation failure. By collecting these results, here, we suggest that CoM has a therapeutic potential against female infertility associated with decreased endometrial receptivity.

Improvement of endometrial receptivity through the use of autologous platelet-derived microparticles

Improvement of endometrial receptivity through the use of autologous platelet-derived microparticles

Impact of Endometrioma Resection on Eutopic Endometrium Metabolite Contents: Noninvasive Evaluation of Endometrium Receptivity

The aim of this study was to determine whether endometrioma resection alters most commonly defined endometrial metabolites, lactate (Lac), N-acetylaspartate (NAA), creatine 1 (Cr1), creatine 2 (Cr2), and choline (Cho) during the window of implantation. Twenty patients with uni- or bilateral endometrioma and 7 patients having nonendometriotic benign ovarian cyst were included. Midluteal phase magnetic resonance spectroscopy analysis of eutopic endometrium was performed before surgery. Second spectrum of endometrium was obtained 3 to 5 months after laparoscopic endometrioma resection. Pre- and postoperative endometrial peaks of Lac, NAA, Cr, and Cho were measured in units and denominated in parts per million (ppm). Compared to preoperative peak values, significantly decreased NAA, Lac, and Cr1 signals were noted in patients undergoing endometrioma surgery. Nearly 5-fold decline in the NAA signal occurred after endometrioma surgery (1.94 ± 3.24 vs 0.37 ± 0.55). Likewise, 2.5-fold decline in Lac signals was noted after endometrioma resection (2.81 ± 2.64 vs 1.06 ± 1.88). Both uni- and bilateral endometrioma affected endometrium signals the same. The peak intensity of Cho, Cr1, Cr2, NAA, and Lac did not alter significantly after nonendometriotic cyst surgery. Endometrioma surgery straightens endometrial NAA, Lac, and Cr1 peaks, suggesting improvement in endometrial receptivity.

Modernization Trends of Infertility Treatment of Traditional Korean Medicine.

Despite the development of assisted reproductive technology (ART), it is difficult to increase the implantation rate. In Korea, Traditional Korean Medicine, including herbal medicine, is an important component of infertility treatment. Korean medical doctors who are treating infertility often use herbal medicine to promote implantation. In this article, as one of the research works on modernization of Traditional Korean Medicine, we investigated the experimental studies to clarify the effects of herbal medicines that are traditionally used to promote pregnancy. We searched for experimental studies over the past 10 years of improvement of endometrial receptivity in herbal medicine using six domestic and international sites. We analyzed 11 studies that meet the selection criteria. We found that herbal medicines demonstrably improved endometrial receptivity and increased pregnancy rates.

The endometrium in assisted reproductive technology: How thin is thin?

A thin endometrium is encountered infrequently (2.4%) in assisted reproductive technology cycles. When it does occur it is a cause of concern as it is associated with lower implantation rate and pregnancy rate. Though pregnancies have been reported at 4 and 5 mm it is apparent that an endometrial thickness <6 mm is associated with a trend toward lower probability of pregnancy. Hormone replacement therapy – frozen embryo transfer (FET) cycles appear to give better results due to an improvement in endometrial receptivity (ER). The etiology of thin endometrium plays a significant part in its receptivity. A number of treatments have been tried to improve endometrial growth, but none has been validated so far. Confirming ER of a thin endometrium by an ER array test before FET offers reassurance.

Laparoscopic endometrioma resection increases peri-implantation endometrial HOXA-10 and HOXA-11 mRNA expression

To determine whether laparoscopic endometrioma resection alters peri-implantation endometrial HOXA-10, HOXA-11, LIF, ITGB3 and ITGAV mRNA expression. Case-control study. Medical school. Twenty infertile patients with uni- or bilateral endometrioma, five infertile patients having nonendometriotic benign ovarian cyst, and five fertile control subjects. Mid-luteal-phase endometrial sampling was performed at the time of surgery. Second endometrial biopsies were obtained 3 months after laparoscopic endometrioma resection during the mid-luteal phase of the cycle. Endometrial HOXA-10, HOXA-11, LIF, ITGAV, and ITGB3 mRNA expressions were evaluated with the use of reverse-transcription polymerase chain reaction. Significantly decreased endometrial ITGAV mRNA expression was noted in biopsies obtained from endometrioma and nonendometriotic cyst groups before surgery. Trends toward decreased endometrial HOXA-10, HOXA-11, LIF, and ITGB3 mRNA expressions were noted in the endometrioma and nonendometriotic cyst groups before surgery compared with the fertile subjects. However, the differences failed to show statistical significance. Compared with preoperative values, significantly increased HOXA-10 (12.1-fold change) and HOXA-11 (17.2-fold change) mRNA expressions were noted in endometrial biopsies obtained from subjects who were undergoing endometrioma surgery. Fold change in endometrial ITGAV mRNA after endometrioma surgery was found to be 30.1 and indicated a positive regulation. However, this fold increase was statistically insignificant. Expressions of these endometrial receptivity markers did not change significantly after surgical removal of nonendometriotic benign ovarian cysts. Laparoscopic endometrioma resection increases peri-implantation endometrial HOXA-10 and HOXA-11 mRNA expression, suggesting an improvement in endometrial receptivity.

Retention and development of eggs transferred to the uterus at various times after ovulation in the rabbit.

The pattern of egg expulsion/retention was determined in rabbits 24 h after transfer of eggs to the uterus 24-84 h p.c. Nearly all eggs transferred at 24 or 36 h p.c. were expelled into the vagina but from 36 h onwards an increasing proportion was retained in utero, although maximum retention was not recorded until 76-84 h p.c. In rabbits in which both uterine horns were ligated before egg transfer at 12-48 h p.c., egg development was evaluated 24 or 72 h later, or at term. Practically all eggs transferred at 12 or 24 h perished within 3 days; however, from transfers at 36 h 25% of eggs implanted with 40% survival to term, and further improvement in endometrial receptivity occurred by 48 h. These findings reveal a clear time difference between limitations imposed by endometrial and myometrial function on egg development. Limited attempts to create more favourable uterine conditions by means of progesterone treatment were unsuccessful.