The enigmatic uterine junctional zone: the missing link between reproductive disorders and major obstetrical disorders?

Intramural Leiomyomas and Fertility: A Systematic Review and Meta-Analysis

OBJECTIVE

To evaluate fertility outcomes based on size and number of intramural leiomyomas and outcomes after removal.

DATA SOURCES

Online searches: MEDLINE, ClinicalTrials.gov, PubMed, Cochrane Library, and PROSPERO Library from 1994 to 2023.

METHODS OF STUDY SELECTION

A total of 5,143 studies were identified, with inclusion of 13 study groups.

TABULATION, INTEGRATION AND RESULTS

Outcomes for size and number of leiomyomas were reported with clinical pregnancy rates and ongoing pregnancy or live-birth rates. In data sets with maximum leiomyoma diameters of less than 6 cm for study inclusion, women with leiomyomas smaller than 3 cm had lower clinical pregnancy rates than women without leiomyomas, with an odds ratio (OR) of 0.53 (95% CI, 0.38-0.76) and, for ongoing pregnancy or live-birth rates, an OR of 0.59 (95% CI, 0.41-0.86). The ORs for clinical pregnancy rates in women with intermediately-sized leiomyomas (those between 3 cm and 6 cm) were lower than in women without leiomyomas, with an OR at 0.43 (95% CI, 0.29-0.63) and, for ongoing pregnancy or live-birth rates, an OR at 0.38 (95% CI, 0.24-0.59). In data sets without exclusion for women with larger-sized leiomyomas, clinical pregnancy rates were lower for those with leiomyomas smaller than 5 cm compared with those without leiomyomas, with an OR of 0.75 (95% CI, 0.58-0.96). Women with leiomyomas larger than 5 cm showed no differences in clinical pregnancy rate compared with women without leiomyomas, with an OR of 0.71 (95% CI, 0.32-1.58). Although women with a single leiomyoma in any location had no differences in outcomes, those with more than one leiomyoma had lower clinical pregnancy rates and ongoing pregnancy or live-birth rates, with an OR of 0.62 (95% CI, 0.44-0.86) and 0.57 (95% CI, 0.36-0.88), respectively. The clinical pregnancy rate for women undergoing myomectomy for intramural leiomyomas was no different than those with intramural leiomyomas in situ, with an OR of 1.10 (95% CI, 0.77-1.59).

CONCLUSION

Even small intramural leiomyomas are associated with lower fertility; removal does not confer benefit. Women with more than one leiomyoma in any location have reduced fertility.

Arrangement into layers and mechanobiology of multi-cell co-culture models of the uterine wall

STUDY QUESTION

Can a co-culture of three cell types mimic the in vivo layers of the uterine wall?

SUMMARY ANSWER

Three protocols tested for co-culture of endometrial epithelial cells (EEC), endometrial stromal cells (ESC), and myometrial smooth muscle cells (MSMC) led to formation of the distinct layers that are characteristic of the structure of the uterine wall in vivo.

WHAT IS KNOWN ALREADY

We previously showed that a layer-by-layer co-culture of EEC and MSMC responded to peristaltic wall shear stresses (WSS) by increasing the polymerization of F-actin in both layers. Other studies showed that WSS induced significant cellular alterations in epithelial and endothelial cells.

STUDY DESIGN, SIZE, DURATION

Human EEC and ESC cell lines and primary MSMC were co-cultured on a collagen-coated synthetic membrane in custom-designed wells. The co-culture model, created by seeding a mixture of all cells at once, was exposed to steady WSS of 0.5 dyne/cm2 for 10 and 30 min.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The co-culture of the three different cells was seeded either layer-by-layer or as a mixture of all cells at once. Validation of the models was by specific immunofluorescence staining and confocal microscopy. Alterations of the cytoskeletal F-actin in response to WSS were analyzed from the 2-dimensional confocal images through the Z-stacks following a previously published algorithm.

MAIN RESULTS AND THE ROLE OF CHANCE

We generated three multi-cell in vitro models of the uterine wall with distinct layers of EEC, ESC, and MSMC that mimic the in vivo morphology. Exposure of the mixed seeding model to WSS induced increased polymerization of F-actin in all the three layers relative to the unexposed controls. Moreover, the increased polymerization of F-actin was higher (P-value < 0.05) when the length of exposure was increased from 10 to 30 min. Furthermore, the inner layers of ESC and MSMC, which are not in direct contact with the applied shearing fluid, also increased their F-actin polymerization.

LARGE SCALE DATA

N/A.

LIMITATIONS, RESONS FOR CAUTION

The mixed seeding co-culture model was exposed to steady WSS of one magnitude, whereas the uterus is a dynamic organ with intra-uterine peristaltic fluid motions that vary in vivo with different time-dependent magnitude. Further in vitro studies may explore the response to peristaltic WSS or other physical and/or hormonal perturbations that may mimic the spectrum of pathophysiological aspects.

WIDER IMPLICATIONS OF THE FINDINGS

Numerous in vitro models were developed in order to mimic the human endometrium and endometrium-myometrium interface (EMI) region. The present co-culture models seem to be the first constructed from EEC, ESC, and MSMC on a collagen-coated synthetic membrane. These multi-cell in vitro models better represent the complex in vivo anatomy of the EMI region. The mixed seeding multi-cell in vitro model may easily be implemented in controlled studies of uterine function in reproduction and the pathogenesis of diseases.

STUDY FINDING/COMPETING INTEREST(S)

This study was supported in part by Tel Aviv University funds. All authors declare no conflict of interest.

Is Neonatal Uterine Bleeding Involved in Early-Onset Endometriosis?

BACKGROUND

There has been considerable progress in our understanding of endometriosis, but its pathophysiology remains uncertain. Uncovering the underlying mechanism of the rare instances of endometriosis reported in early postmenarcheal years and in girls before menarche can have wide implications.

METHODS

We conducted a literature review of all relevant articles on Medline.

RESULTS

In the review, we explore the pathogenetic theories of premenarcheal endometriosis, the role of retrograde menstruation in the adult and its potential role in early-onset disease, as well as the factors that argue against the existence of a link between early-onset endometriosis (EOE) and neonatal uterine bleeding (NUB).

CONCLUSIONS

As with endometriosis in adult women, the pathogenesis of early-onset disease remains unclear. A link between NUB and EOE is plausible, but there are considerable challenges to collating supporting evidence. The state of our understanding of early uterine development and of the pathophysiology of NUB leaves many unknowns that need exploration. These include proof of the existence of viable endometrial cells or endometrial mesenchymal stem cells in NUB, their passage to the pelvic cavity, their possible response to steroids, and whether they can reside within the pelvic cavity and remain dormant till menarche.

Effect of aging on the human myometrium at single-cell resolution

Age-associated myometrial dysfunction can prompt complications during pregnancy and labor, which is one of the factors contributing to the 7.8-fold increase in maternal mortality in women over 40. Using single-cell/single-nucleus RNA sequencing and spatial transcriptomics, we have constructed a cellular atlas of the aging myometrium from 186,120 cells across twenty perimenopausal and postmenopausal women. We identify 23 myometrial cell subpopulations, including contractile and venous capillary cells as well as immune-modulated fibroblasts. Myometrial aging leads to fewer contractile capillary cells, a reduced level of ion channel expression in smooth muscle cells, and impaired gene expression in endothelial, smooth muscle, fibroblast, perivascular, and immune cells. We observe altered myometrial cell-to-cell communication as an aging hallmark, which associated with the loss of 25 signaling pathways, including those related to angiogenesis, tissue repair, contractility, immunity, and nervous system regulation. These insights may contribute to a better understanding of the complications faced by older individuals during pregnancy and labor.

Junctional zone thickening: an endo-myometrial unit disorder

Adenomyosis is a disease defined by histopathology, mostly of hysterectomy specimens, and classification is challenged by the disagreement of the histologic definition. With the introduction of Magnetic Resonance Imaging (MRI) and two- and three-dimensional ultrasound, the diagnosis of adenomyosis became a clinical entity. In MRI and US, adenomyosis ranges from thickening of the inner myometrium or junctional zone to nodular, cystic, or diffuse lesions involving the entire uterine wall, up to a well-circumscribed adenomyoma or a polypoid adenomyoma. The absence of an accepted classification and the vague and inconsistent terminology hamper basic and clinical research. The sub-endometrial halo seen at US and MRI is a distinct entity, differing from the outer myometrium by its increased nuclear density and vascular structure. The endometrium and the sub-endometrial muscularis or archimetra are of Müllarian origin, while the outer myometrium is non-Mullerian mesenchymal. The junctional zone (JZ) is important for uterine contractions, conception, implantation, and placentation. Thickening of the JZ can be considered inner myometrium adenomyosis, with or without endometrial invasion. Changes in the JZ should be considered a different entity than myometrial clinically associated with impaired conception, implantation, abnormal uterine bleeding, pelvic pain and obstetrical outcome. Pathology of the basal endometrium and JZ is a separate entity and should be identified as an endo-myometrial unit disorder (EMUD).

The role of the junctional zone in the management of adenomyosis with infertility

The junctional zone (JZ) is an important structure in the myometrium that maintains uterine fertility. Changes in the junctional zone are closely related to infertility and adenomyosis (ADS). As an increasing number of young women are affected by ADS, the disease is no longer considered typical of women over 40. With these changes, an increasing number of patients refuse hysterectomy and desire fertility preservation treatment. At the same time, ADS is a crucial factor causing female infertility. Therefore, the treatment of ADS-related infertility and preservation of reproductive function is one of the other major challenges facing clinicians. For these young patients, preserving fertility and even promoting reproduction has become a new challenge. Therefore, we searched and summarized these studies on PubMed and Google Scholar using keywords such as "adenomyosis", "junctional zone", and "infertility" to explore infertility causes, diagnosis, and treatment of ADS patients who wish to preserve their uterus or fertility and become pregnant, focusing on the junctional zone, to obtain a full appreciation of the new perspective on this disease.

MRI for Diagnosing Intrauterine Adhesions

OBJECTIVES

To prospectively assess the diagnostic accuracy of MRI and transvaginal ultrasound (TVS) as well as the prognostic value of MRI for intrauterine adhesions (IUAs), using hysteroscopy as the reference standard.

DESIGN

Prospective observational study.

SETTING

Tertiary medical centre.

PATIENT(S)

Ninety-two women with amenorrhea, hypomenorrhea, subfertility, or recurrent pregnancy loss who underwent MRI and in whom Asherman's syndrome was suspected upon TVS.

INTERVENTION(S)

MRI and TVS were conducted approximately 1 week before hysteroscopy.

METHODS

Ninety-two patients suspected of having Asherman's syndrome were examined by MRI and TVS within 7 days of an upcoming hysteroscopy. All hysteroscopy procedures were performed during the early proliferative phase of the menstrual cycle. All hysteroscopic diagnoses were performed by an experienced expert. All MRIs were read by 2 experienced, blinded radiologists.

RESULTS

MRI was highly accurate (94.57%), sensitive (98.8%), and specific (42.9%) for diagnosing IUAs with a positive predictive value of 95.5% and a negative predictive value of 75%. The diagnostic values of MRI and TVS were significantly different according to McNemar tests. Junctional zone signal and junctional zone alterations correlated with the stage of IUAs.

CONCLUSION

MRI is markedly superior to TVS in terms of diagnostic accuracy for IUAs, with total agreement with hysteroscopic findings. However, the main advantage of MRI is that, unlike TVS and hysterosalpingography, it can be used to assess the risk of hysteroscopy and to predict postoperative recovery and future pregnancy based on the uterine junctional zone.

The ADENO study: ADenomyosis and its Effect on Neonatal and Obstetric outcomes: a retrospective population-based study

BACKGROUND

Adenomyosis is a benign gynecologic condition arising from the uterine junctional zone. Recent studies suggest a relationship between adenomyosis and adverse obstetrical outcomes, but evidence remains conflicting. There is no large-scale study investigating obstetrical outcomes in women with adenomyosis using the gold standard of histopathologic diagnosis.

OBJECTIVE

This study aimed to investigate the prevalence of adverse obstetrical and neonatal outcomes in women with histopathologic adenomyosis and that of the general (Dutch) population.

STUDY DESIGN

This retrospective population-based study used 2 Dutch national databases (Perined, the perinatal registry, and the nationwide pathology databank [Pathologisch Anatomisch Landelijk Geautomiseerd Archief], from 1995 to 2018) to compare obstetrical outcomes in women before histopathologic adenomyosis diagnosis to the general Dutch population without registered histopathologic adenomyosis. The adjusted odds ratios (95% confidence interval) were calculated for adverse obstetrical outcomes. The outcomes were adjusted for maternal age, parity, ethnicity, year of registered birth, induction of labor, hypertensive disorders in previous pregnancies, multiple gestation, and low socioeconomic status.

RESULTS

The pregnancy outcomes of 7925 women with histopathologic adenomyosis were compared with that of 4,615,803 women without registered adenomyosis. When adjusted for confounders, women with adenomyosis had adjusted odds ratios of 1.37 (95% confidence interval, 1.25-1.50) for hypertensive disorders, 1.37 (95% confidence interval, 1.25-1.51) for preeclampsia, 1.15 (95% confidence interval, 1.07-1.25) for small-for-gestational-age infants, 1.54 (95% confidence interval, 1.41-1.68) for emergency cesarean delivery, 1.24 (95% confidence interval, 1.12-1.37) for failure to progress, 1.29 (95% confidence interval, 1.10-1.48) for placental retention, and 1.23 (95% confidence interval, 1.10-1.38) for postpartum hemorrhage. No increased risk of HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome, placental abruption, or operative vaginal delivery or need for oxytocin stimulation was found.

CONCLUSION

Women with a histopathologic diagnosis of adenomyosis showed an increased prevalence of hypertensive disorders of pregnancy and small-for-gestational-age infants, failure to progress in labor, and placental retention compared with the general population in previous pregnancies. This suggests that uterine (contractile) function in labor and during pregnancy is impaired in women with adenomyosis.

A Study on the Prediction of Reproductive Outcomes in Frozen Embryo Transfer Cycles by Calculating the Volume of Uterine Junctional Zone with Three-Dimensional Ultrasound

PURPOSE

To prospectively study the influence of the volume of the uterine junctional zone (JZ) as a novel predictor of reproductive outcomes in frozen embryo transfer cycles.

METHODS

Among the first 30 patients, intra- and interobserver repeatability was evaluated and expressed as a coefficient of repeatability. The same classification system was used to evaluate the JZ of 142 infertility patients undergoing in vitro fertilization (IVF). Ultrasonography was performed on the day before transplantation. The three-dimensional (3D) volume images were then analyzed to obtain the volume of the endometrium (EV), the average thickness of the JZ on the coronal plane, and the volume of the JZ (JZV). The JZV was then divided by the EV. These parameters were compared with the outcomes of clinical pregnancy.

RESULTS

The 3D image showed that the JZ achieved a good intra- and interobserver consistency (k = 0.862, k = 0.694). The total pregnancy rate was 47%. There was a highly significant difference between pregnant and non-pregnant women with respect to age (p < 0.001), JZV (p = 0.003), and JZV/EV (p < 0.001) on the day before transplantation. Age and JZV/EV were independent factors for predicting the success of IVF transplantation (p = 0.010, p = 0.016). The area under the ROC curve of JZV/EV in predicting clinical pregnancy was 0.688, the cut-off value was 0.54, the sensitivity was 83.8%, and the specificity was 50.0%.

CONCLUSION

Age and JZV/EV are independent factors for predicting the success of frozen embryo transfer cycles in IVF. A smaller JZV/EV was more beneficial for clinical pregnancy.

How adenomyosis changes throughout pregnancy: A retrospective cohort study

OBJECTIVE

To study how adenomyosis changes during pregnancy and to possibly correlate these changes to maternal and fetal outcomes.

METHODS

Retrospective exploratory cohort study including 254 women with a pre-conceptional/first-trimester scan to document adenomyosis and known obstetric outcome. If visible, adenomyosis signs were documented in each trimester and postpartum. Mann-Whitney U tests or χ² tests were used for continuous and categorical variables, respectively.

RESULTS

A globular uterus was reported in 79% (n = 52) of women with adenomyosis in the first trimester, in 38% (n = 20) and 2% (n = 1) of women in the second and third trimesters, respectively, and postpartum in 77% (n = 34) of women. Asymmetrical thickening (n = 20, 30%) and cysts (n = 15, 23%) were only visible in 1st trimester. Adenomyosis was associated with miscarriage (odds ratio [OR] 5.9, 95% confidence interval [CI] 2.4-14.9, P < 0.001) also in normal conception only (OR 5.1, 95% CI 1.8-14.2, P = 0.002) or adjusting for maternal age (adjusted OR 5.9, 95% CI 2.3-15.2, P < 0.001). Gestational age at delivery was lower in adenomyosis (P = 0.004); the cesarean section rate was higher than in controls (OR 2.5, 95% CI 1.3-4.8, P = 0.007) also adjusting for age (adjusted OR 2.07, 95% CI 1.06-4.08, P = 0.035).

CONCLUSIONS

Signs of adenomyosis were visible but progressively disappeared in pregnancy; adenomyosis was associated with an increased risk of early miscarriage. Prospective studies are needed to confirm our results.

Oleuropein suppresses endometriosis progression and improves the fertility of mice with endometriosis

BACKGROUND

Endometriosis is an estrogen-dependent inflammatory reproductive disease. Therefore, systematic estrogen depletion and anti-inflammatory drugs are the current treatment for endometriosis. However, current endometriosis treatments have low efficacy and cause adverse effects in endometriosis patients. Consequently, alternative endometriosis treatments targeting endometriosis-specific factors are in demand. In this context, ERβ was selected as a druggable target for endometriosis due to its critical role in progression. Therefore, selective targeting of ERβ without inhibiting ERα activity would be a new paradigm for endometriosis treatment to overcome the low efficacy and adverse effects of hormonal endometriosis therapy.

METHODS

Cell-based ERβ and ERα activity assay systems were employed to define a selective ERβ-inhibiting chemical product from a library of natural products. A surgically induced endometriosis mouse model was used to determine whether an ERβ inhibitory drug suppressed endometriosis progression. Mice with endometriosis were randomly separated and then orally treated with vehicle or 25 mg/kg oleuropein (once a day for 21 days), an ERβ inhibitory drug. The volume of endometriotic lesions or luciferase activity of endometriotic lesions was examined to define the growth of ectopic lesions in mice with endometriosis. The metabolite and levels of metabolic enzymes of the liver and kidney were determined in the serum of female mice treated with vehicle and oleuropein (25 mg/kg, once a day for 21 days) to define the toxicity of oleuropein. The in vitro decidualization assay was conducted with normal human endometrial stromal cells and endometriotic stromal cells to determine whether oleuropein overcomes decidualization in endometriosis patients. The pregnancy rate and pup numbers of C57BL/6 J female mice with endometriosis treated with vehicle or oleuropein (n = 10/group) were determined after mating with male mice. The cytokine profile in endometriotic lesions treated with vehicle and oleuropein (25 mg/kg) was determined with a Mouse Cytokine Array Kit.

RESULTS

Among natural products, oleuropein selectively inhibited ERβ but not ERα activity in vitro. Oleuropein treatment inhibited the nuclear localization of ERβ in human endometrial cells upon estradiol treatment. Oleuropein (25 mg/kg) treatment suppressed the growth of mouse (6.6-fold) and human (sixfold) ectopic lesions in mice with endometriosis compared to the vehicle by inhibiting proliferation and activating apoptosis in endometriotic lesions. Oleuropein treatment did not cause reproductive toxicity in female mice. Additionally, mice with endometriosis subjected to oleuropein treatment had a higher pregnancy rate (100%) than vehicle-treated mice (70%). Furthermore, oleuropein treatment partially recovered the decidualization impact of human endometriotic stromal cells from endometriotic lesions compared to the vehicle. Oleuropein-treated mice with endometriosis exhibited significantly lower levels of cytokines directly regulated by ERβ in ectopic lesions than vehicle-treated mice, illustrating the improvement in the hyperinflammatory state of mice with endometriosis.

CONCLUSIONS

Oleuropein is a promising and novel nutraceutical product for nonhormonal therapy of endometriosis because it selectively inhibits ERβ, but not ERα, to suppress endometriosis progression and improve the fertility of mice with endometriosis.

Uterine junctional zone and adenomyosis: comparison of MRI, transvaginal ultrasound and histology

The uterine junctional zone is the subendometrial area in the myometrium that contributes to peristalsis and aids in spermatozoa and blastocyst transport. Alterations in the appearance of the junctional zone on transvaginal sonography (TVS) or magnetic resonance imaging (MRI) are associated with adenomyosis. The lack of standardization of description of its appearance and ill-defined boundaries on both histology and imaging hamper understanding of the junctional zone and limit its role in the diagnosis of adenomyosis. The objectives of this review were to investigate the accordance in definition of the junctional zone across different diagnostic approaches and to examine how imaging findings can be linked to histological findings in the context of diagnosis of adenomyosis. A comprehensive literature review was conducted of articles describing the appearance on imaging and the histological structure of the uterine junctional zone. Our review suggests that the junctional zone is distinguished from the middle and outer myometrium by gradual changes in smooth-muscle cell density, extracellular space, connective tissue, water content and vascular properties. However, while the signal intensity from the junctional zone to the middle myometrium changes abruptly on MRI, the histopathological changes are gradual and its border may be difficult or impossible to distinguish on two-dimensional TVS. Moreover, the thickness of the junctional zone measured on MRI is larger than that measured on TVS. Thus, these two imaging modalities reflect this zone differently. Although a thickened junctional zone is often used to diagnose adenomyosis on MRI, the presence of adenomyosis can be described more accurately as interruptions of the junctional zone by endometrial tissue, which leads to direct signs on imaging such as subendometrial lines and buds on two- and three-dimensional TVS or bright foci on MRI. The histopathological criteria for diagnosis are based on enlargement of the uterus with severe adenomyosis, and might not reflect its early stages. Clinicians should be aware that findings on MRI cannot be extrapolated readily to ultrasound. An understanding of this is necessary when investigating the uterine junctional zone as a functional unit and the association between visualization of direct features of adenomyosis in the junctional zone and clinical symptoms. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Cracking the enigma of adenomyosis: an update on its pathogenesis and pathophysiology

In brief

Traditionally viewed as enigmatic and elusive, adenomyosis is a fairly common gynecological disease but is under-recognized and under-researched. This review summarizes the latest development on the pathogenesis and pathophysiology of adenomyosis, which have important implications for imaging diagnosis of the disease and for the development of non-hormonal therapeutics.

Abstract

Traditionally considered as an enigmatic disease, adenomyosis is a uterine disease that affects many women of reproductive age and is a contributing factor for pelvic pain, heavy menstrual bleeding (HMB), and subfertility. In this review, the new development in the pathogenesis and pathophysiology of adenomyosis has been summarized, along with their clinical implications. After reviewing the progress in our understanding of the pathogenesis and describing the prevailing theories, in conjunction with their deficiencies, a new hypothesis, called endometrial-myometrial interface disruption (EMID), which is backed by extensive epidemiologic data and demonstrated by a mouse model, is reviewed, along with recent data implicating the role of Schwann cells in the EMI area in the genesis of adenomyosis. Additionally, the natural history of adenomyotic lesions is elaborated and underscores that, in essence, adenomyotic lesions are fundamentally wounds undergoing repeated tissue injury and repair (ReTIAR), which progress to fibrosis through epithelial-mesenchymal transition, fibroblast-to-myofibroblast transdifferentiation, and smooth muscle metaplasia. Increasing lesional fibrosis propagates into the neighboring EMI and endometrium. The increased endometrial fibrosis, with ensuing greater tissue stiffness, results in attenuated prostaglandin E2, hypoxia signaling and glycolysis, impairing endometrial repair and causing HMB. Compared with adenomyosis-associated HMB, the mechanisms underlying adenomyosis-associated pain are less understood but presumably involve increased uterine contractility, hyperinnervation, increased lesional production of pain mediators, and central sensitization. Viewed through the prism of ReTIAR, a new imaging technique can be used to diagnose adenomyosis more accurately and informatively and possibly help to choose the best treatment modality.

Perioperative Suppression of Schwann Cell Dedifferentiation Reduces the Risk of Adenomyosis Resulting from Endometrial–Myometrial Interface Disruption in Mice

We have recently demonstrated that endometrial–myometrial interface (EMI) disruption (EMID) can cause adenomyosis in mice, providing experimental evidence for the well-documented epidemiological finding that iatrogenic uterine procedures increase the risk of adenomyosis. To further elucidate its underlying mechanisms, we designed this study to test the hypothesis that Schwann cells (SCs) dedifferentiating after EMID facilitate the genesis of adenomyosis, but the suppression of SC dedifferentiation perioperatively reduces the risk. We treated mice perioperatively with either mitogen-activated protein kinase kinase (MEK)/extracellular-signal regulated protein kinase (ERK) or c-Jun N-terminal kinase (JNK) inhibitors or a vehicle 4 h before and 24 h, 48 h and 72 h after the EMID procedure. We found that EMID resulted in progressive SCs dedifferentiation, concomitant with an increased abundance of epithelial cells in the myometrium and a subsequent epithelial–mesenchymal transition (EMT). This EMID-induced change was abrogated significantly with perioperative administration of JNK or MEK/ERK inhibitors. Consistently, perioperative administration of a JNK or a MEK/ERK inhibitor reduced the incidence by nearly 33.5% and 14.3%, respectively, in conjunction with reduced myometrial infiltration of adenomyosis and alleviation of adenomyosis-associated hyperalgesia. Both treatments significantly decelerated the establishment of adenomyosis and progression of EMT, fibroblast-to-myofibroblast trans-differentiation and fibrogenesis in adenomyotic lesions. Thus, we provide the first piece of evidence strongly implicating the involvement of SCs in the pathogenesis of adenomyosis induced by EMID.

In vivo evaluation of endometrium through dual-modality intrauterine endoscopy

Female infertilities are highly associated with poor endometrial receptivity. A receptive endometrium is generally characterized by the normal uterine cavity, intact endometrial surface, appropriate endometrial thickness, and echo pattern. Acquiring comprehensive structural information is the prerequisite of endometrium assessment, which is beyond the ability of any single-modality imaging method. In this paper, we introduce a custom-made intrauterine dual-modality (OCT/ultrasound) endoscopic imaging system and achieve in vivo imaging of rabbit uteri, for the first time to our knowledge. The endometrial features of the injured uteri in both ultrasonic and OCT images are consistent with their corresponding pathology. The quantified parameters, including uterine thickness and endometrial surface roughness, show the correlation with the endometrial injury degree but with poor performance for injury classification. The combination of these parameters was proved to assess the degrees of endometrial injury more accurately. Our work shows the potential of the dual-modality system to be translated into a clinical tool, providing multiple quantitative imaging information and helping evaluate the endometrial receptivity and diagnose infertility.

First trimester HtrA1 maternal plasma level and spontaneous preterm birth

OBJECTIVES

High temperature requirement A1 (HtrA1) is a serine protease detected in maternal plasma and in placental tissues during normal gestation and in various pathological conditions. The purpose of this study was to determine whether the maternal plasma concentration of HtrA1 in first trimester, alone or combined with other maternal factors, can be used to identify women at risk for spontaneous preterm birth (SPTB).

STUDY DESIGN

This is a cohort study on pregnant women at 12 weeks of gestation recruited between 2014 and 2016 and prospectively followed until delivery. One hundred and fifty-nine women were included in the study: 140 women delivered at term and 19 (11.9%) delivered spontaneously preterm. Plasma samples were assessed for HtrA1 by ELISA and data were compared between women which delivered at term with women which delivered preterm. A multiple logistic regression analysis was used to estimate the independent effect of women's characteristics on the probability of a SPTB.

RESULTS

SPTB was significantly associated with log HtrA1 values at 12 weeks of gestation, BMI before pregnancy and physical activity. In particular, the probability of a SPTB increases of 79% for every added unit of log HtrA1, while decreases of 18% for every added unit of BMI. In addition, physical activity was found as an important protective factor. The ROC curve showed that the model had a good accuracy in predicting SPTB, with an AUC equal to 0.83 (95%CI: 0.73-0.91).

CONCLUSIONS

Maternal plasma HtrA1 may be considered a marker of SPTB. In addition, our model indicates two factors that could be modified to reduce the risk of SPTB, i.e. BMI before pregnancy and maternal physical activity.

Mode Switch of Ca2 + Oscillation-Mediated Uterine Peristalsis and Associated Embryo Implantation Impairments in Mouse Adenomyosis

Adenomyosis is a debilitating gynecological disease of the uterus with no medicinal cure. The tissue injury and repair hypothesis for adenomyosis suggests that uterine hyperperistalsis or dysperistalsis plays a pivotal role in establishing adenomyotic lesions. However, specific impairments in uterine peristalsis and the underlying cellular signals for these changes in adenomyosis remain elusive. Here, we report a precision-cut uterine slice preparation that preserves in vivo uterine architecture and generates peristalsis similar to that seen in the whole uterus. We found that uterine peristalsis in neonatal mice at day 14 and adult mice at day 55 presents as bursts with multiple peaks induced by intracellular Ca²⁺ oscillations. Using a mouse model of adenomyosis induced by tamoxifen, a selective estrogen receptor modulator, we discovered that uterine peristalsis and Ca²⁺ oscillations from adenomyotic uteri on days 14 and 55 become spikes (single peaks) with smaller amplitudes. The peak frequency of Ca²⁺ oscillations or peristalsis does not show a difference between control and adenomyotic mice. However, both the estimated force generated by uterine peristalsis and the total Ca²⁺ raised by Ca²⁺ oscillations are smaller in uteri from adenomyotic mice. Uteri from adenomyotic mice on day 14, but not on day 55, exhibit hyperresponsiveness to oxytocin. Embryo implantations are decreased in adenomyotic adult mice. Our results reveal a mode switch from bursts to spikes (rather than an increased peak frequency) of uterine Ca²⁺ oscillations and peristalsis and concurrent hyperresponsiveness to oxytocin in the neonatal stage are two characteristics of adenomyosis. These characteristics may contribute to embryo implantation impairments and decreased fertility in adenomyosis.

Maternal-Fetal Outcomes in Women with Endometriosis and Shared Pathogenic Mechanisms

The connection between endometriosis and pregnancy outcomes is trending among the research topics. Until recently, endometriosis and its painful symptomatology were considered to be alleviated by pregnancy. However, these beliefs have shifted, as emerging literature has demonstrated the role of this condition in affecting pregnancy evolution. The underlying pathogenesis of endometriosis is still poorly understood, all the more when pregnancy complications are involved. Debatable opinions on endometriosis associated with obstetric complications exist because of the potential bias resulting from the heterogeneity of preceding evidence. This review aims to evaluate the connection between endometriosis and adverse pregnancy outcomes and their shared pathogenic mechanisms. We searched PubMed and EMBASE and focused on the studies that include placenta praevia, premature rupture of membranes, spontaneous preterm birth, gestational hypertension, preeclampsia, obstetric hemorrhages (ante- and postpartum bleeding, abruptio placentae), miscarriage, stillbirth, neonatal death, gestational diabetes mellitus, gestational cholestasis, small for gestational age, and their association with endometriosis. Not only the risks of emergence were highlighted, but also the pathogenic connections. Epigenetic alterations of some genes were found to be mirrored both in endometriosis and obstetric complications. This review issues a warning for providing increased attention to pregnant women with endometriosis and newborns as higher risks of preeclampsia, placental issues, and preterm deliveries are associated.

Adenomyosis and infertility: the role of the junctional zone

OBJECTIVE

Adenomyosis is a benign uterine disorder characterized by the invasion of the endometrium within the myometrium, starting from the junctional zone (JZ), the inner hormone dependent layer of the myometrium that plays an important role in sperm transport, implantation and placentation. The resulting histological abnormalities and functional defects may represent the pathogenic substrate for infertility and pregnancy complications. The objective of this paper is to review the literature to evaluate the correlation between inner myometrium alterations and infertility and to assess the role of JZ in the origin of adverse obstetric outcomes of both spontaneous and in vitro fertilization (IVF) pregnancies.

METHODS

we searched Pubmed for all original and review articles in the English language from January1962 until December 2019, using the MeSH terms of 'adenomyosis', 'junctional zone', combined with 'infertility', 'obstetrical outcomes', 'spontaneous conception', 'in vitro fertilization' and 'classification'. The review was divided into three sections to assess this pathogenic correlation, evaluating also the importance of classification of the disease.

RESULTS AND CONCLUSIONS

Absent or incomplete remodeling of the JZ can affect uterine peristalsis, alter vascular plasticity of the spiral arteries and activate inflammatory pathways, all related to adverse obstetric outcomes. Despite these observations, there is still limited evidence whether adenomyosis is a cause of infertility. However, it is reasonable to screen patients for adenomyosis, to consider pregnant women with diffuse adenomyosis at high risk of adverse obstetric outcomes, and to evaluate the importance of a noninvasive validated classification in the management of women with adenomyosis.

Effects of localisation of uterine adenomyosis on outcome of in vitro fertilisation/intracytoplasmic sperm injection fresh and frozen-thawed embryo transfer cycles: a multicentre retrospective cohort study

BACKGROUND

Uterine adenomyosis is a benign disease, common among women in their 40 and 50 s, characterised by ectopic endometrial tissue in the uterine myometrial layer. Adenomyosis causes infertility and has a negative effect on the outcomes of in vitro fertilisation (IVF)/intracytoplasmic sperm injection (ICSI) embryo transfer (ET) cycles. It has also been reported to have different characteristics depending on the adenomyotic lesion localisation. The effect of its localisation on IVF/ICSI-ET outcomes is unclear. This study aimed to investigate whether adenomyotic lesion localisation, assessed using magnetic resonance imaging (MRI), was associated with outcomes of IVF/ICSI-ET cycles.

METHODS

This multicentre, joint, retrospective cohort study analysed the medical records of 67 infertile patients with adenomyosis who underwent IVF/ICSI with fresh and frozen-thawed ET at five participating facilities from January 2012 to December 2016 and for whom MRI data were available. Fifteen patients were excluded; therefore, the MRI data of 52 patients were evaluated by two radiologists. We assessed the localisation of and classified adenomyotic lesions into advanced (invades the full thickness of the uterine myometrium), extrinsic (localised on the serosal side), and intrinsic (localised on the endometrial side) subtypes.

RESULTS

There were 40 advanced, nine extrinsic, and three intrinsic cases, and the outcomes of 100, 27, and nine ET cycles, respectively, were analysed. Pregnancy loss/clinical pregnancy and live birth rates of the advanced, extrinsic, and intrinsic groups were 64 % (16/25) and 9 % (9/100), 33.3 % (3/9) and 22.2 % (6/27), and 50 % (1/2) and 11.1 % (1/9), respectively. A logistic regression analysis adjusted for age, prior miscarriage, and body mass index showed that the extrinsic group had fewer pregnancy losses (odds ratio 0.06; 95 % confidence interval [CI]: 0.00-0.54, p = 0.026) and more live births (odds ratio 6.05; 95 % CI: 1.41-29.65, p = 0.018) than the advanced group.

CONCLUSIONS

Adenomyotic lesions exert different effects on IVF/ICSI-ET outcomes. Thus, MRI assessments of adenomyosis in infertile patients are beneficial. Establishment of treatment plans based on adenomyotic lesion localisation should be considered.

Adenomyosis as a Potential Risk Factor for Adverse Pregnancy Outcomes: A Multicenter Case-Control Study

As the number of women who postpone their first pregnancy until their late 30s or early 40s is increasing, adenomyosis is more frequently encountered by obstetricians. Some studies have reported on the relationship between adenomyosis and pregnancy complications. We aimed to investigate the effect of adenomyosis on pregnancy complications and outcomes and associations between adenomyosis type and pregnancy outcomes. This multicenter retrospective 1:4 case-control study included 61 women with singleton pregnancies diagnosed with adenomyosis. The control group included women with singleton pregnancies without adenomyosis; these women were matched to those with adenomyosis using propensity scores. The incidence of obstetric complications, delivery, and neonatal outcomes were compared. The adenomyosis group (n = 61) had significantly higher incidence of preterm delivery (21.3% vs. 9.4%), hypertensive disorders of pregnancy (13.1% vs. 5.3%), cesarean delivery (46.0% vs. 20.9%), and postpartum hemorrhage (57.3% vs. 36.8%) than the control group (n = 244). Subgroup analysis by the adenomyosis type revealed that the diffuse adenomyosis group (n = 41) was significantly more likely to experience preterm labor (29.3% vs. 7.3%), hypertensive disorders of pregnancy (17.0% vs. 5.5%), severe hypertensive disorders of pregnancy (12.2% vs. 1.8%), preterm premature rupture of membranes (12.2% vs. 2.4%), cesarean delivery (61.3% vs. 18.9%), and postpartum hemorrhage (70.7% vs. 44.5%) than the control group (n = 164). The focal adenomyosis (n = 20) group was not statistically different from the control group (n = 80) with respect to obstetric complications. Women with diffuse adenomyosis require more careful perinatal management than previously thought.

Perinatal outcomes associated with the positional relationship between the placenta and the adenomyosis lesion

INTRODUCTION

Although various perinatal complications have been reported to be increased in the pregnant patients with adenomyosis, it is not clear what type of patients with adenomyosis is more likely to cause obstetric complications. In this study, we focused on the positional relationship between the placenta and adenomyosis lesion in evaluating perinatal prognosis of pregnant patients with adenomyosis.

MATERIAL AND METHODS

This retrospective cohort study was carried out between 1 January 2005 and 31 December 2019 in a single institution. Adenomyosis was diagnosed by magnetic resonance imaging (MRI) and/or transvaginal ultrasonography (TVUS). To evaluate the influence of adenomyosis on perinatal outcomes, we classified the positional relationship between the placenta and the adenomyosis lesion into two groups and examined the perinatal prognosis of the patients with adenomyosis by analyzing their clinical records. Group I (n = 9) was defined when the placenta was not overlaid on adenomyosis lesion. Group II (n = 11) was defined when a part of the placenta was overlaid on adenomyosis lesion.

RESULTS

Twenty pregnant patients with adenomyosis were analyzed. There were no differences in clinical backgrounds between group I and group II. There was a significant increase in the obstetric morbidity in group II than that of Group I(group I: 6.3%, 4/63 vs group II: 18.6%, 26/77; P < 0.001). In group II, fetal growth restriction (FGR) was more frequent (0%, 0/9 vs 45.5%, 5/11; P = 0.042) and the birth weight was significantly lower than that in group I (2951.1 g ± 326.5 g vs 2318.9 ± 656.1 g; P = 0.037). There was a trend of lighter weight of the placenta in group II (550.6 ± 66.5 g vs 437.5 ± 117.8 g; P = 0.063) and the volume of bleeding during delivery was a higher trend in group II than that in group I (845.1 ± 367.1 g vs 1356 ± 604.8 g; P = 0.083). Group II was furtherly subdivided into group IIa (less than half the major axis of the placenta overlaid on adenomyosis lesion) and group IIb (more than half the major axis of placenta overlaid on adenomyosis lesion). The obstetric morbidity tended to be higher in group IIb than in group IIa (group IIa: 22.9%, 8/35 vs group IIb: 42.9%, 18/42); P = 0.09). In group IIb, the frequency of FGR was significantly higher (group IIa: 0%, 0/5 vs IIb: 83.3%, 5/6; P = 0.020) and the birth weight was significantly lower than those in group IIa (2656.8 ± 231.9 g vs 2037 ± 780.1 g; P = 0.040). All cases of FGR, hypertensive disorder of pregnancy (HDP), and oligohydramnios were observed in group IIb.

CONCLUSION

Placental localization near adenomyosis may increase the risk of perinatal complications.

Endometriosis and Risk of Adverse Pregnancy Outcome: A Systematic Review and Meta-Analysis

Background: This systematic review and meta-analysis summarizes the evidence for the association between endometriosis and adverse pregnancy outcome, including gestational hypertension, pre-eclampsia, low birth weight, and small for gestational age, preterm birth, placenta previa, placental abruption, cesarean section, stillbirth, postpartum hemorrhage, spontaneous hemoperitoneum in pregnancy, and spontaneous bowel perforation in pregnancy. Methods: We performed the literature review in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA), by searches in PubMed and EMBASE, until 1 November 2020 (PROSPERO ID CRD42020213999). We included peer-reviewed observational cohort studies and case-control studies and scored them according to the Newcastle–Ottawa Scale, to assess the risk of bias and confounding. Results: 39 studies were included. Women with endometriosis had an increased risk of gestational hypertension, pre-eclampsia, preterm birth, placenta previa, placental abruption, cesarean section, and stillbirth, compared to women without endometriosis. These results remained unchanged in sub-analyses, including studies on spontaneous pregnancies only. Spontaneous hemoperitoneum in pregnancy and bowel perforation seemed to be associated with endometriosis; however, the studies were few and did not meet the inclusion criteria. Conclusions: The literature shows that endometriosis is associated with an increased risk of gestational hypertension, pre-eclampsia, preterm birth, placenta previa, placental abruption, cesarean section, and stillbirth.

Pregnancy outcomes of Chinese women undergoing IVF with embryonic cryopreservation as compared to natural conception

Background

To examine differences in the maternal characteristics and pregnancy outcomes of Chinese women with various causes of infertility who underwent in vitro fertilization (IVF) with embryonic cryopreservation treatment.

Methods

Cases were pregnancies after IVF-ET with embryonic cryopreservation; controls were spontaneously conceived pregnancies. Subgroup analysis was carried out according to etiology of infertility. The IVF treatment group was divided into 5 subgroups according to infertility etiology as follows: ovulation disorder, tubal disease, male infertility, endometriosis, and mixed infertility. Data on demographic characteristics, medical history, laboratory tests, and delivery were reviewed. Logistic regression analysis was performed for pregnancy and perinatal complications and neonatal outcomes. The multivariable model was adjusted for potential confounders.

Results

Among singleton pregnancies, compared with spontaneous pregnancies, IVF pregnancies were associated with significant increases in the rates of the following: gestational diabetes mellitus (GDM) (aOR 1.76[95% CI 1.33–2.33]), preeclampsia (2.60[1.61–4.20]), preterm preeclampsia (4.52[2.03–10.06]), postpartum hemorrhage (1.57[1.04–2.36]), intrahepatic cholestasis of pregnancy (3.84[1.06–13.94]), preterm premature rupture of membranes (2.11[1.17–3.81]), preterm birth (1.95[CI 1.26–3.01]), low birthweight (1.90[1.13–3.20]), macrosomia (1.53[1.03–2.27]), and neonatal intensive care unit (NICU) admission (1.69[1.22–2.34]) in the ovulation disorder group; GDM (1.50[1.21–1.86]), placenta previa (2.70[1.59–4.59]), placenta accreta (1.78[1.10–2.89]), postpartum hemorrhage (1.61[1.19–2.18]), macrosomia (1.60[1.21–2.13]) and 5-min Apgar score ≤ 7 (4.09[1.04–16.08]) in the tubal disease group; placenta previa (9.33[4.22–20.62]), small for gestational age (2.29[1.04–5.08]), macrosomia (2.00[1.02–3.95]) and NICU admission (2.35[1.35–4.09]) in the endometriosis group; placenta previa (4.14[2.23–7.68]) and placenta accreta (2.05[1.08–3.87]) in the male infertility group; and GDM (1.85[1.15–2.98]), placenta previa (4.73[1.83–12.21]), placental abruption (3.39[1.20–9.56]), chorioamnionitis (2.93[1.04–8.26]), preterm birth (2.69[1.41–5.15]), and 1-min Apgar score ≤ 7 (4.68[1.62–13.51]) in the mixed infertility group. Among multiple pregnancies, most of the differences that were significant in singleton pregnancies were less extensive or had disappeared.

Conclusions

Infertility etiology within the IVF population was found to affect maternal and neonatal outcomes among all births. During the perinatal period, infertility etiology appears to be an additional risk factor for abnormal pregnancy outcomes besides the use of IVF techniques compared with spontaneous pregnancies. Higher risk was found for ovulation disorders, and lower risk was found for male infertility.

Deep Learning Based Junctional Zone Quantification using 3D Transvaginal Ultrasound in Assisted Reproduction

The Uterine Junctional Zone (JZ) is identified as an important anatomical region in the implantation process during assisted reproduction. The JZ changes throughout the hormone stimulation cycle and has predictive value for implantation success. Despite advances in imaging technique, the assessment of JZ remains an enigma. The state-of-the-art method to assess the JZ is largely manual, which is time consuming, depends on operator experience, and often introduces subjective bias in assessment. In this paper, we present methods for automated visualization and quantification of the JZ in three-dimensional transvaginal ultrasound imaging (3D-TVUS). JZ is best visualized in the midcoronal plane of the 3D-TVUS uterus acquisition. We propose an algorithm pipeline, which uses a deep learning model to generate a point cloud representing the surface of the endometrium. A regularized midcoronal surface passing through the point cloud is rendered to obtain the midcoronal plane. The automated solution is designed to accommodate multiple structural deformations and pathologies in the uterus. An expert assisted reproduction clinician on 136 3D-TVUS volumes evaluated the results, and reliable performance was observed in more than 89% cases where the automated solution is able to reproduce, and sometimes even outperform the manual workflow. Automation speeds up the clinical workflow approximately by a factor of ten and reduces operator bias.

Impairment of Uterine Contractility Is Associated with Unexplained Infertility

The uterine junctional zone represents the juncture between endometrium and myometrium. The junctional zone is hormonally dependent and displays continuous peristaltic activity throughout the menstrual cycle in the nonpregnant state which is concerned with sperm transport and embryo implantation. Peristalsis may be observed using various invasive and noninvasive modalities, of which ultrasound is the most readily applied in the clinical setting. Women with pelvic pathology display alterations in uterine peristalsis which may contribute to infertility. Characterization of peristalsis in infertility subgroups, the development of a subjective peristalsis tool, and the application of potential therapeutics to an assisted reproductive treatment setting are the subject of ongoing investigation. Meta-analysis indicates a potential role for oxytocin antagonist in the improvement of fertility treatments.

Junctional zone endometrium alterations in gynecological and obstetrical disorders and impact on diagnosis, prognosis and treatment

PURPOSE OF REVIEW

To investigate the JZE alterations in gynecological and obstetrical disorders and impact on diagnosis, prognosis and treatment.

RECENT FINDINGS

JZE was found to be significantly extended in patients with endometriosis, leading to the conclusion that endometriosis is a primary disease of the uterus, much like adenomyosis. Statistical correlation was then demonstrated between the severity of endometriosis and the depth of the adenomyosis infiltrates, hence the thickening of the JZE. Stem cells, predominantly found in the JZE were also found in histological sections of leiomyoma, suggested to be the origin of leiomyoma. This reservoir of JZE stem cells is influenced by different stressors leading to their differentiation into leiomyoma, endometriosis, adenomyosis or endometrial cancer, according to the stressor. The variability in presentation was hypothesized to be connected to genetic and epigenetic factors. JZE was also suggested to act as a barrier, stopping endometrial carcinoma cells invasion and metastasis. In addition, JZE plays a major role in conception, pregnancy and postpartum.

SUMMARY

JZE is an important anatomical landmark of the uterus contributing to normal uterine function under the influence of ovarian hormones. Alterations of the JZE thickness and contractility can be used as pathognomonic clinical markers in infertility and chronic pelvic pain, for subendometrial and myometrial disorders, for example, adenomyosis and fibroids. Prospective randomized control trials will clarify the diagnostic steps, imaging modalities to follow and probably triage the patients between medical and surgical treatments.

Altered VEGF, Bcl-2 and IDH1 expression in patients with adenomyosis

PURPOSE

Adenomyosis is a benign uterine disease resulting from the myometrial invasion of the endometrial gland and stroma. In the current study, angiogenesis, apoptosis and energy metabolism were investigated in adenomyosis.

METHODS

A retrospective study was performed using paraffin archival tissues. Three groups were included in the study: Group I and Group II; ectopic and eutopic endometrial tissues of patients with adenomyosis, respectively, and Control Group; endometrial tissue of individuals without adenomyosis. Vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), intercellular adhesion molecule 1 (ICAM-1) and hypoxia-inducible factor 1 alpha (HIF-1A) levels were evaluated as angiogenic markers. Bcl-2, caspase-9 and caspase-3 levels were investigated as apoptotic indicators, and isocitrate dehydrogenase 1 (IDH1), succinate dehydrogenase complex subunit C (SDHC) and fumarate hydratase (FH) levels were also examined as energy metabolism markers. Gene expression levels of all parameters were determined by RT-PCR.

RESULT

VEGF expression levels were found to be increased in Group I according to the control group and Group II. Bcl-2 expression levels were found to be increased in the Group I compared to the Group II. It was determined that expression levels of IDH1 were decreased in the Group I and Group II compared to the Control Group. There was no significant difference in the other examined parameters. Although we did not find a significant difference in HIF-1A levels between the groups, we found a positive correlation between VEGF and HIF-1A in the Group I.

CONCLUSION

These results point out that VEGF, HIF-1A, Bcl-2 and IDH1 may be associated with the etiology of adenomyosis.

Pathophysiologic mechanisms by which adenomyosis predisposes to postpartum haemorrhage and other obstetric complications

Adenomyosis is characterized by the presence of ectopic endometrium within the myometrium. This features lead to structural changes in the surrounding myometrium and endometrium resulting also in functional changes. Alterations in the myometrium are suspected to lead to defective remodeling of spiral arteries during the early stages of decidualization resulting in altered vascular resistance and defective placentation. These alterations could play a common part in the association between adenomyosis and major obstetric complications. Latest epidemiological studies show that adenomyosis is associated with preterm birth, preeclampsia, IUGR and increased caesarean section rates, but very little is known of any underlying mechanism linking postpartum hemorrhage and adenomyosis. It is our opinion that adenomyosis may increase the risk of postpartum hemorrhage through several mechanisms that will be further clarified. Women with adenomyosis may require specific management during pregnancy and may benefit from wider understanding of the pathological mechanisms associated with this disease process.

The importance of the junctional zone of the endometrium in human reproduction

Junctional zone endometrium (JZE) thickness and contractility seem to determine gamete and embryo transportation and implantation. Proper function depends on concentration levels, mode and timing of oestrogen and progesterone production. Most probably, the remodelling of spiral arteries, and the development of endometrium and decidua are also highly dependent on JZE activity. Fibroids that are adjacent to JZE affect JZE contractility contributing to abnormal or failed implantation. Disruption of the JZE continuity provokes adenomyosis, a condition that causes chronic inflammation and fibrosis, which negatively affects the normal function of JZE. Imaging by magnetic resonance imaging and three-dimensional sonography can diagnose JZE abnormal appearance, alterations in thickening and contractility frequency, usually in the advanced stage of the disease. Failures of assisted reproduction, and adverse early pregnancy outcomes have also been associated with abnormal JZE. Altered uterine contractions due to JZE changes are strongly associated with poor reproductive outcome and early pregnancy loss. Endometriosis and adenomyosis prevalently co-exist, with clear relation and negative effects on the JZE. The presence of endometriosis should alert to the possibility of coexisting adenomyosis. Co-existence of endometriosis may mask the extent of the negative impact of adenomyosis in infertility.

Endometriosis and Pregnancy: A Single Institution Experience

Endometriosis may compromise the physiological course of pregnancy. The aim of this prospective observational study was to evaluate whether endometriosis causes a higher prevalence of obstetric and neonatal complications as well as a higher risk of caesarean section and to detect a possible correlation between the presence, type, and location of endometriosis and obstetric complications, previous surgery, and pregnancy outcome, as well as the influence of pregnancy on the course of the disease. We compared two cohorts of women with spontaneous pregnancy, with and without endometriosis. Obstetric and neonatal outcomes, mode of delivery, presence, type, and location of endometriotic lesions and the effect of pregnancy on the disease were analyzed. A total of 425 pregnancies were evaluated: 145 cases and 280 controls. Patients with endometriosis showed a higher incidence of miscarriage, threatened miscarriage, threatened preterm labor, preterm delivery, placental abruption, and a higher incidence of caesarean section. A significant correlation with pregnancy-induced hypertension and preeclampsia was found in the presence of adenomyosis. No difference in fetal outcome was found. One case of hemoperitoneum during pregnancy was observed. Pregnancy in women with endometriosis carries a higher risk of obstetric complications, such as miscarriage, threatened miscarriage, preterm labor, preterm birth, and a higher caesarean section rate. Endometriosis does not seem to influence fetal well-being.

Recent advances in understanding and managing adenomyosis

Adenomyosis is a benign uterine disorder in which endometrial glands and stroma are pathologically demonstrated in the uterine myometrium and it is considered a specific entity in the PALM-COEIN FIGO (polyp; adenomyosis; leiomyoma; malignancy and hyperplasia; coagulopathy; ovulatory dysfunction; endometrial; iatrogenic; and not yet classified - International Federation of Gynecology and Obstetrics) classification of causes of abnormal uterine bleeding (AUB). Although it has always been considered the classic condition of multiparous women over 40 years old who have pain and heavy menstrual bleeding, diagnosed at hysterectomy, the epidemiological scenario has completely changed. Adenomyosis is increasingly identified in young women with pain, AUB, infertility, or no symptoms by using imaging techniques such as transvaginal ultrasound and magnetic resonance. However, there is no agreement on the definition and classification of adenomyotic lesions from both the histopathology and the imaging point of view, and the diagnosis remains difficult and unclear. A uniform and shared reporting system needs to be implemented in order to improve our understanding on imaging features, their relationship with pathogenic theories, and their importance in terms of clinical symptoms and response to treatment. In fact, adenomyosis pathogenesis remains elusive and not a single theory can explain all of the different phenotypes of the disease. Furthermore, adenomyosis often coexists with other gynecological conditions, such as endometriosis and uterine fibroids, increasing the heterogeneity of available data. Treatment requires a lifelong management plan as the disease has a negative impact on quality of life in terms of menstrual symptoms, fertility, and pregnancy outcome and has a high risk of miscarriage and obstetric complications.

Symptoms and classification of uterine adenomyosis, including the place of hysteroscopy in diagnosis

Where histology used the presence of glands and/or stroma in the myometrium as pathognomonic for adenomyosis, imaging uses the appearance of the myometrium, the presence of striations, related to the presence of endometrial tissue within the myometrium, the presence of intramyometrial cystic structures and the size and asymmetry of the uterus to identify adenomyosis. Preliminary reports show a good correlation between the features detected by imaging and the histological findings. Symptoms associated with adenomyosis are abnormal uterine bleeding, pelvic pain (dysmenorrhea, chronic pelvic pain, dyspareunia), and impaired reproduction. However a high incidence of existing comorbidity like fibroids and endometriosis makes it difficult to attribute a specific pathognomonic symptom to adenomyosis. Heterogeneity in the reported pregnancy rates after assisted reproduction is due to the use of different ovarian stimulation protocols and absence of a correct description of the adenomyotic pathology. Current efforts to classify the disease contributed a lot in elucidated the potential characteristics that a classification system should be relied on. The need for a comprehensive, user friendly, and clear categorization of adenomyosis including the pattern, location, histological variants, and the myometrial zone seems to be an urgent need. With the uterus as a possible unifying link between adenomyosis and endometriosis, exploration of the uterus should not only be restricted to the hysteroscopic exploration of the uterine cavity but in a fusion with ultrasound.

Expression Pattern of G-Protein-Coupled Estrogen Receptor in Myometrium of Uteri with and without Adenomyosis

Objective

To compare the expression of G-protein-coupled estrogen receptor (GPER) in the junctional zone and outer myometrium of the proliferative and secretory phases of women with and without adenomyosis.

Methods

A total of 76 women were included in this study, 42 with adenomyosis (proliferative phase, n = 23; secretory phases, n = 19) and 34 controls (proliferative phase, n = 16; secretory phases, n = 18). Protein and total RNA were extracted from the junctional zone (JZ) and outer myometrium (OM). GPER protein and mRNA expression levels were evaluated by the use of western blotting and real-time quantitative polymerase chain reaction (RT-qPCR).

Results

The expression of GPER protein and mRNA in women with adenomyosis was significantly higher than that of control subjects, both in the junctional zone and in the outer myometrium and both in the proliferative and in the secretory phases.

Conclusion

The significant and consistent increase in GPER expression in adenomyosis compared with control subjects, regardless of whether it was in the proliferative or secretory phases and regardless of whether it was in the JZ or OM, suggests that GPER plays an important role in the pathogenesis of the adenomyosis.

Complications and outcomes of pregnant women with adenomyosis in Japan

Purpose

To investigate the impact of adenomyosis on the complications and outcomes of pregnancy in Japan.

Methods

We carried out a multicenter retrospective questionnaire survey. A questionnaire regarding pregnancy complications and the outcomes of pregnancy was sent to 725 facilities.

Results

Data were obtained on the cases of 272 pregnant women with adenomyosis from 65 facilities. The complications of pregnancy included miscarriage before 12 weeks of pregnancy (14.8%), miscarriage after 12 weeks of pregnancy (9.9%), preterm delivery (24.4%), fetal growth restriction (11.8%), pregnancy‐induced hypertension (9.9%), intrauterine infection (7.3%), and cervical incompetency (5.3%). The rates of pregnancy complications in the three groups classified according to pretreatment for adenomyosis (no pretreatment, medication, surgery) did not differ to a statistically significant extent. The rates of miscarriage (>12 weeks) and cervical incompetency increased according to the size of the adenomyosis. The rates of pregnancy‐induced hypertension and uterine infection in patients with diffuse‐type adenomyosis were higher than that in patients with focal‐type adenomyosis.

Conclusions

Our results show that the increased size and diffuse type of adenomyosis are associated with adverse pregnancy outcome. We should be aware of the higher incidence of pregnancy‐induced hypertension and uterine infection in patients with diffuse‐type adenomyosis.

[Endometriosis and miscarriage: Systematic review]

OBJECTIVES

In spontaneous pregnancies, endometriosis appears to be a risk factor of miscarriage. The aim of this study is to evaluate the association between endometriosis and miscarriage in spontaneous pregnancy.

METHODS

We searched the Cochrane Library, Medline of eligible studies from inception to December 2016, without any restriction. We selected studies that compared endometriosis-affected pregnant women to disease-free pregnant women. To ensure the quality of the methodology, the PRISMA criteria have been met at all stages of the development of this meta-analysis. The primary adverse pregnancy outcomes studied was miscarriage. Three reviewers independently extracted the studies' characteristics and outcome data.

RESULTS

Of 225 identified abstracts, 4 primary studies met our inclusion criteria by comparing spontaneous pregnant patients with endometriosis to disease-free women. Miscarriage rate was higher in the endometriosis group (OR 1.77 [CI 95% 1.13-2.78]).

CONCLUSION

In spontaneous pregnancies, endometriosis appears to be a risk factor of miscarriages (almost 80% increased risk). Further prospective studies are needed to confirm these results in order to establish the exact impact of endometriosis on spontaneous pregnancy course.

The role of the placenta in the initiation of spiral artery remodelling in an early pregnant chimpanzee uterus

INTRODUCTION

In this study we evaluated the full extent of placental bed changes (centre to periphery) in a pregnant chimpanzee uterus, kept at the Museum for Central Africa in Tervuren, Belgium. According to placental size the specimen was equivalent to an 8 weeks pregnant human uterus.

METHODS

Histological sections from central to peripheral tissue blocks of the placental bed were stained to reveal the presence of trophoblast, endothelium, vascular smooth muscle and elastic laminae. As an indicator for early arterial remodelling, we evaluated endothelial nuclear rounding and subendothelial vascular changes within the maternal vasculature in decidua and adjacent inner myometrium.

RESULTS

While interstitially invading trophoblasts were present, endovascular trophoblast invasion seemed about to start into one spiral artery outlet at the centre of the placental bed, confirming our previous impression of a later onset of endovascular trophoblast invasion as compared to the human. An early sign of spiral artery remodelling was rounding of the endothelial nuclei. This phenomenon was not related to the local presence of interstitial trophoblast.

DISCUSSION

Endothelial nuclear rounding turned out to be a feature of the placental bed as a whole, being significantly less prominent in the adjacent non-placental bed part of the uterus, indicating an effect of the presence of the placenta. The different time-course of early spiral artery remodelling in the chimpanzee as compared to the human may have had a significant impact upon our evolution.

Failure of physiologic transformation of spiral arteries, endothelial and trophoblast cell activation, and acute atherosis in the basal plate of the placenta

BACKGROUND

Failure of physiologic transformation of spiral arteries has been reported in preeclampsia, fetal growth restriction, fetal death, and spontaneous preterm labor with intact or ruptured membranes. Spiral arteries with failure of physiologic transformation are prone to develop atherosclerotic-like lesions of atherosis. There are striking parallels between preeclampsia and atherosclerotic disease, and between lesions of atherosis and atherosclerosis. Endothelial activation, identified by intercellular adhesion molecule-1 expression, is present in atherosclerotic-like lesions of heart transplantation, and is considered a manifestation of rejection. Similarly, endothelial activation/dysfunction has been implicated in the pathophysiology of atherosclerosis and preeclampsia. Intercellular adhesion molecule-1-overexpressing-activated endothelial cells are more resistant to trophoblast displacement than nonactivated endothelium, and may contribute to shallow spiral artery trophoblastic invasion in obstetrical syndromes having failure of physiologic transformation.

OBJECTIVE

We sought to determine whether failure of spiral artery physiologic transformation was associated with activation of interstitial extravillous trophoblasts and/or spiral artery endothelium and presence of acute atherosis in the placental basal plate.

STUDY DESIGN

A cross-sectional study of 123 placentas (19-42 weeks' gestation) obtained from normal pregnancies (n = 22), preterm prelabor rupture of membranes (n = 26), preterm labor (n = 23), preeclampsia (n = 27), intrauterine fetal death (n = 15), and small for gestational age (n = 10) was performed. Failure of spiral artery physiologic transformation and presence of cell activation was determined using immunohistochemistry of placental basal plates containing a median of 4 (minimum: 1; maximum: 9) vessels per placenta. Endothelial/trophoblast cell activation was defined by the expression of intercellular adhesion molecule-1. Investigators examining microscopic sections were blinded to clinical diagnosis. Pairwise comparisons among placenta groups were performed with Fisher exact test and Wilcoxon rank sum test using a Bonferroni-adjusted level of significance (.025).

RESULTS

We found that 87% (94/108) of placentas having spiral arteries with failure of physiologic transformation (actin-positive and cytokeratin-negative) in the basal plate, and 0% (0/15) of placentas having only spiral arteries with complete physiologic transformation (cytokeratin-positive and actin-negative), had arterial endothelial and/or interstitial extravillous trophoblasts reactive with the intercellular adhesion molecule-1 activation marker (P < .001). A significant correlation (R² = 0.84) was found between expression of spiral artery endothelial and interstitial extravillous trophoblast intercellular adhesion molecule-1 (P < .001) in activated placentas. Lesions of atherosis were found in 31.9% (30/94) of placentas with complete and/or partial failure of physiologic transformation of spiral arteries that were intercellular adhesion molecule-1-positive, in none of the 14 placentas with failure of physiologic transformation that were intercellular adhesion molecule-1-negative, and in none of the 15 placentas with complete spiral artery physiologic transformation without failure (P = .001). All placentas (30/30, 100%) with atherosis were identified in placentas having concomitant spiral artery endothelial and interstitial extravillous trophoblast activation.

CONCLUSION

Failure of spiral artery physiologic transformation in the placental basal plate is associated with interstitial extravillous trophoblast and arterial endothelial activation along with increased frequency of spiral artery atherosis. These findings may be used to improve the characterization of different disorders of the placental bed such as in refining the existing tools for the early prediction of risk for preterm, preeclamptic, and other abnormal pregnancies.

Assessment of the uterus with three-dimensional ultrasound in women undergoing ART

BACKGROUND

A detailed assessment of the uterus forms a pivotal part of the ART treatment process. The emergence of three-dimensional ultrasound (3D US) has provided clinicians with a highly powerful tool in this respect. Assessments with 3D US range from the reconstruction of anatomical planes elusive to conventional US, to the objective measurement of anatomical volumes and vascularization parameters. However, despite the ever increasing number of publications emerging in the literature, the question of which aspects of 3D US are of most clinical value remains a topic of debate.

OBJECTIVE AND RATIONALE

The objective of this review is to dissect which aspects of the 3D US assessment of the uterus are supported by a strong level of evidence to date, and should therefore be incorporated into current routine clinical practice.

SEARCH METHODS

We conducted a systematic search of the PubMed database up to May 2016, using a combination of text words and Medical Subject Headings (MeSH) pertaining to the 3D US assessment of the uterus. All articles published in the English language were screened to ascertain relevance to women of reproductive age; further citations were retrieved through manual reference list searching.

OUTCOMES

A multitude of predominantly observational studies were identified, which concerned a vast variety of 3D US uterine assessments. All articles unequivocally praised the non-invasive, cost-effective, highly acceptable and objective nature of 3D US. Studies regarding the value of assessing the endometrial volume and vascularization prior to embryo transfer appeared conflicting and inconsistent. Studies regarding the imaging of uterine pathology and identification of intratubal and intrauterine devices consistently reported high rates of diagnostic accuracy. A recent RCT did not show an improvement in clinical outcomes when comparing 3D versus 2D US during embryo transfer. However, preliminary studies suggested that 3D US is superior in determining the site of implantation, particularly in ambiguous cases such as interstitial and angular pregnancies. Finally, pilot studies have suggested that the further integration of 3D and possibly 4D US with surgical interventions of the uterus may be a promising prospect.

WIDER IMPLICATIONS

3D US may prove to be an invaluable tool in the assessment of the uterus within the context of ART. Currently, the aim should be to highlight the aspects of 3D US that are most evidence-based and valuable for patients, and to incorporate these into routine clinical practice.

The Role of Adenomyosis in the Pathogenesis of Preeclampsia

INTRODUCTION

Adenomyosis can cause defective deep placentation. Preeclampsia is known to be associated with abnormal placentation. The aim of this study was to compare the presence of adenomyosis on magnetic resonance imaging in patients with and without history of preeclampsia in order to investigate the possible role of adenomyosis in the pathogenesis of preeclampsia.

MATERIALS AND METHODS

This prospective, randomized study consisted of patients with (n = 35) and without (n = 34) history of preeclampsia. Direct (submucosal microcysts, adenomyoma and cystic adenomyoma) and indirect (maximal thickness of junctional zone, ratio of maximal thickness of junctional zone to myometrial thickness, junctional zone differential, focal thickening of junctional zone, globally enlarged uterus and non-uniform junctional zone contours) signs of adenomyosis were assessed by pelvic magnetic resonance imaging.

RESULTS

The prevalence of adenomyosis was found to be more common in patients with preeclampsia und fetal growth restriction compared to patients without fetal growth restriction (94.4 vs. 64.7 %; p = 0.041), respectively. There was a strong association between maximal thickness of junctional zone (9 vs. 13 mm, p = 0.005), ratio of maximal thickness of junctional zone to myometrial thickness (0.42 vs. 0.66, p = 0.001) and junctional zone differential (3 vs. 5 mm, p = 0.02) and late-onset preeclampsia.

CONCLUSIONS

Presence of adenomyoma is more common in patients with preeclampsia complicated with fetal growth restriction. Indirect signs of adenomyosis detected on pelvic magnetic resonance imaging might have a role in the pathogenesis of late-onset preeclampsia.

Uterine junctional zone thickness in infertile women evaluated by MRI

PURPOSE

To prospectively evaluate and compare the junctional zone (JZ) and outer myometrial thickness in infertile and healthy nulliparous women at different locations in the uterine wall during the menstrual cycle by magnetic resonance imaging (MRI).

MATERIALS AND METHODS

We performed pelvic 1.5T MRI (T₂ -weighted turbo spin echo sequences) on 28 infertile women: 5 with infertility of unknown origin, 12 anovulating, and 11 on ovarian stimulation therapy (mean age 28.5, 30.8, and 29.3 years, respectively); and a control group consisting of 18 healthy nulliparous volunteers (mean age 26.4 years). The women with unknown infertility origin and the control group underwent MRI investigations during their follicular, ovulatory, and luteal phase. The JZ and outer myometrial thicknesses were measured at six locations in the uterine wall: anterior and posterior wall of the isthmus, midcorpus, and fundus.

RESULTS

The JZ in the anovulating women at the posterior wall of the isthmus (4.2 mm) was significantly thicker compared to the control group (3.2, 3.0, and 2.9 mm, in respectively the three menstrual phases) (P = 0.027). The outer myometrium in the anovulating women was significantly thicker at all measured locations (average 11.5 mm) in comparison to the control group (8.1, 8.0, and 8.5 mm, in respectively the three menstrual phases) (P < 0.050). The infertile women on ovarian stimulation therapy showed a significantly thicker outer myometrium at the anterior wall (isthmus, midcorpus, and fundus) (P < 0.050).

CONCLUSION

The results indicate that a thickened JZ, and especially a thickened outer myometrium, might be associated with infertility.

LEVEL OF EVIDENCE

1 J. Magn. Reson. Imaging 2017;45:926-936.

Repeatability of Junctional Zone Measurements Using 3-Dimensional Transvaginal Sonography in Healthy Fertile Women

OBJECTIVES

To describe the junctional zone and determine the intraobserver and interobserver repeatability of junctional zone measurements using 3-dimensional (3D) transvaginal sonography in healthy fertile women.

METHODS

We examined 82 consecutive women with 3D transvaginal sonography. The maximum and minimum junctional zone thickness was measured in all uterine walls. The difference between maximum and minimum thickness and average measurements (maximum thickness + minimum thickness/2) of the anterior, posterior, fundal, and lateral walls were calculated. Among the first 40 consecutive women, intraobserver and interobserver repeatability was evaluated according to the Bland-Altman method and expressed as a coefficient of repeatability.

RESULTS

Using 3D transvaginal sonography, we visualized a thin and regular junctional zone in most women. The posterior uterine wall had the largest median maximum junctional zone thickness value of 5.2 (interquartile range, 3.8-6.5) mm. Ten women (12%) had maximum thickness values of 8.0 to 12.0 mm. The maximum thickness in each uterine wall had intraobserver and interobserver coefficients of repeatability of ±2.1 to ±3.4 and ±2.6 to ±3.9 mm, respectively, which were reduced by average measurements: ±1.9 and ±2.0 mm (anterior and posterior walls) and ±1.5 mm (fundal and lateral walls) for intraobserver and interobserver values. Correlations between measurements were poor in the narrow range of junctional zone thickness.

CONCLUSIONS

The junctional zone has an indistinct outline on 3D transvaginal sonography, resulting in measurement errors within a broad range of ±2 to ±4 mm, which were only reduced to some extent by average measurements. The thickness of the junctional zone varied within a narrow range in this healthy fertile population, and reliability measurements of junctional zone thickness have to be evaluated in women with a wider range of thickness. The observer repeatability and reliability of junctional zone measurements need to be further evaluated and refined before applying this method in clinical practice.

Optimal uterine anatomy and physiology necessary for normal implantation and placentation

The authors review aberrations of uterine anatomy and physiology affecting pregnancy outcomes with IVF. In the case of endometriosis and hydrosalpinx, pathologies outside of the uterus alter the uterine endometrium. In the case of endometriosis, Dominique de Ziegler outlines the numerous changes in gene expression and the central role of inflammation in causing progesterone resistance. With endometriosis, the absence of ovarian function inherent in deferred transfer, with or without a more lengthy suppression of ovarian function, appears to be sufficient to restore normal function of eutopic endometrium. Because laparoscopy is no longer routine in the evaluation of infertility, unrecognized endometriosis then becomes irrelevant in the context of assisted reproductive technology. With hydrosalpinx and submucus myomas, the implantation factor HOXA-10 is suppressed in the endometrium and, with myomas, even in areas of the uterus not directly affected. Daniela Galliano reviews various uterine pathologies, the most enigmatic being adenomyosis, where the endometrium also manifests many of the changes seen in endometriosis and deferred transfer with extended suppression appears to provide the best outcomes. Ettore Cicinelli's group has extensively studied the diagnosis and treatment of endometritis, and although more definitive diagnosis and care of this covert disorder may await techniques such as sequencing of the endometrial microbiome, it undoubtedly is an important factor in implantation failure, deserving our attention and treatment.