Local peritoneal factors: their role in infertility associated with endometriosis

Fas-Related Apoptosis of Peritoneal Fluid Macrophages in Endometriosis Patients: Understanding the Disease

Recent studies of the peritoneal cavity environment in endometriosis demonstrate quantitative and qualitative changes in the cells responsible for cell-mediated immunity. Such changes may have led to disturbances in the surveillance, recognition, and destruction of misplaced endometrial cells and might have, in fact, brought about the disease. The aim of the study was to assess CD95 (Fas) expression on (activated) peritoneal fluid (PF) macrophages, as well as to ascertain soluble Fas (sFas) concentration in the PF of endometriosis patients, as compared to the nonendometriotic group. The concentration of leukocytes in the PF, the percentage of cells expressing CD45⁺/CD14⁺, and the percentage of PF macrophages expressing the HLA-DR antigen were significantly higher in patients with stages I and II endometriosis. The percentage of Fas- (CD95⁺-) expressing macrophages was significantly higher in all stages of the disease, in comparison with controls. Moreover, the concentration of sFas in the PF of patients with moderate and severe endometriosis was significantly higher, as compared to the reference group. The high number of immune cells in PF in early stage endometriosis and their increased susceptibility to apoptosis confirm the role of the impaired peritoneal environment and immune defects in the development and progression of the disease.

Endometriosis-induced alterations in mouse metaphase II oocyte microtubules and chromosomal alignment: a possible cause of infertility

OBJECTIVE

To examine the effect of peritoneal fluid (PF) of patients with endometriosis on the cytoskeleton of metaphase II oocytes and correlate the results with the stage of endometriosis and the duration of infertility.

DESIGN

Prospective-controlled study.

SETTING

Center for reproductive medicine at a tertiary-care hospital.

PATIENT(S)

Women with endometriosis (n=23) and tubal ligation/reversal (n=15).

INTERVENTION(S)

Peritoneal fluid obtained from 38 women (23 with endometriosis and 15 tubal ligation/reversal) after laparoscopy. Four hundred metaphase II oocytes were used: 165 frozen metaphase II oocytes were incubated in the PF of patients with endometriosis, 135 oocytes incubated in the PF of nonendometriosis patients (control subjects) and 100 oocytes incubated in human tubal fluid (HTF) media.

MAIN OUTCOME MEASURE(S)

Spindle abnormalities (microtubule and chromosomal) were evaluated by confocal imaging.

RESULT(S)

In the endometriosis group, the cytoskeleton had a higher frequency of abnormal meiotic spindle and chromosomal misalignment (score ≥3), indicating severe damage compared with the control groups. The proportions of abnormalities in microtubule and chromosome alterations in endometriosis (67.9% and 63.6%, respectively) were significantly higher than for oocytes incubated with PF of the nonendometriosis group (24.4% and 14.8%) as well as the HTF group (13% and 13%). Oocyte cytoskeleton damage positively correlated with the duration of infertility and the stage of endometriosis.

CONCLUSION(S)

Alteration of oocyte cytoskeleton might be one of the causes of poor oocyte quality in patients with endometriosis.

Pathological evaluation of uterine leiomyomas treated with gonadotropin-releasing hormone agonist (GnRH-a) therapy: role of mast cells and a possible mechanism of GnRH-a resistance in leiomyomas

Gonadotropin-releasing hormone agonist (GnRH-a) therapy is frequently applied to reduce the volume of uterine leiomyomas (UL). In addition, the possible relationship between mast cells (MC) within UL and the development of UL has been suggested, but the role of MC in UL remains to be determined. UL with or without GnRH-a therapy in 121 premenopausal patients were reviewed. The number of MC was evaluated between the two groups, immunohistochemistry was done for insulin-like growth factor-I (IGF-I), and the association between the IGF-I immunoreactivity in UL and the GnRH-a therapy was analyzed. The number of MC significantly increased in UL in GnRH-a therapy, while IGF-I immunoreactivity was significantly reduced in smooth muscle cells of these UL. Furthermore, IGF-I immunoreactivity in MC was inversely correlated with the size reduction rate of UL in GnRH-a therapy. Although GnRH-a therapy is considered to reduce the size of UL transiently, the regression of UL was in part hampered by the increased IGF-I secretion from the increased MC after GnRH-a therapy. Therefore, the more the IGF-I secretion from MC in UL increases, the less effective the GnRH-a therapy is on the size reduction of UL. Thus, the present study may provide an explanation of the possible mechanism of GnRH-a resistance in UL.

L-carnitine supplementation reduces oocyte cytoskeleton damage and embryo apoptosis induced by incubation in peritoneal fluid from patients with endometriosis

OBJECTIVE

To investigate the protective effect of L-carnitine (LC) against deleterious substances present in the peritoneal fluid (PF) of patients with endometriosis, which may affect the oocyte cytoskeleton and embryogenesis.

DESIGN

Experimental study.

SETTING

Research embryology laboratory at an academic hospital.

PATIENT(S)

Frozen metaphase II mouse oocytes and embryos.

INTERVENTION(S)

One hundred metaphase II mouse oocytes were divided into five groups and incubated: PF from endometriosis patients; PF from endometriosis patients + LC; PF from tubal ligation patients (patient control); LC only; and human tubal fluid (HTF) alone. A total of 180 eight-cell mouse embryos were divided into: endometriosis only; tubal ligation only; endometriosis + LC; LC alone; and HTF alone.

MAIN OUTCOME MEASURE(S)

Protective effect of LC on oocytes and embryos.

RESULT(S)

Incubation of the oocytes and the embryos with PF from patients with endometriosis statistically significantly damaged the oocyte microtubules and chromosomes and increased embryo apoptosis compared with controls. Incubation with LC (0.6 mg/mL) statistically significantly improved microtubule and chromosome structure and decreased the level of embryo apoptosis.

CONCLUSION(S)

We propose the use of LC as a supplement in patients with endometriosis, a novel approach that may help improve in vitro fertilization outcome in these patients.

Pyruvate reduces in vitro the embryotoxic effect of peritoneal fluid from infertile women with endometriosis

OBJECTIVES

To ascertain the embryotoxicity of peritoneal fluid from infertile women with endometriosis (PF-E), on mouse embryos in culture and to examine the effect of pyruvate in the culture medium on PF-E induced embryotoxicity.

STUDY DESIGN

Blood-free peritoneal fluid samples were obtained during laparoscopic investigation for infertility from 21 infertile women with endometriosis. The severity of endometriosis ranged from minimal or mild (PF-min to mild-E; n=7), moderate (PF-mod-E; n=7), to severe (PF-sev-E; n=7). Peritoneal fluid samples were centrifuged at 600 x g for 10 min and 4 degrees C, and the supernatant was incubated at 56 degrees C for 30 min in a water bath to inactivate the complement protein. Mice were super ovulated with intraperitoneal injection (IP) of 5IU of pregnant mare serum gonadotrophin and human chorion gonadotrophin. Twenty-four hours after confirmation of mating two-cell mouse embryos were obtained. They were then cultured in modified Whitten's medium (mWM) with peritoneal fluid from patients with endometriosis, and either in the absence or presence of excess pyruvate (0.062 mmol(-1)). Embryos were cultured for 72 h.

RESULTS AND CONCLUSION

Addition of 5% PF-E significantly (p<0.001) suppressed embryo growth at 24, 48, and 72 h of culture and the degree of suppression correlated with the severity of the disease. The presence of 0.062 mmol(-1) pyruvate in the culture medium significantly (p<0.001) reduced the embryotoxicity of PF-min to mild-E and PF-mod-E at each stage of development, but was only seen at 24h of culture (p<0.001) in cultures with PF-sev-E even when the concentration of pyruvate in the medium was increased to 0.31 mmol(-1). This study confirms the embryotoxicity of PF-E in vitro, which was reduced by the presence pyruvate in the culture medium, particularly in cultures containing fluid from women with endometriosis of minimum or mild to moderate severity.

Effect of ovarian involvement on peritoneal fluid cytokine concentrations in endometriosis patients

Peritoneal fluid cytokines are important for initiation and progression of endometriosis. The objective of this study was to compare a group of five cytokines (interleukins IL-1 beta, IL-6, IL-8, IL-13 and tumour necrosis factor alpha; TNFalpha) in peritoneal fluid of endometriosis patients with ovarian involvement (Group I, n = 17) to those in patients without ovarian involvement (Group II, n = 33) and to a reference group without endometriosis (Group III, n = 25). All three groups were comparable regarding age, parity and body mass index. IL-8 concentrations were significantly higher in groups I and II compared with the reference group (P = 0.01 and 0.02, respectively). Similarly, TNFalpha concentrations were significantly higher in groups I and II compared with the reference group (P < 0.0001 and 0.0004, respectively). All other cytokines were comparable in the three groups. No significant differences were found between groups I and II with respect to the cytokines measured. In conclusion, peritoneal fluid IL-8 and TNFalpha concentrations are significantly higher in endometriosis. Ovarian involvement does not alter the pattern of cytokines. It appears that the inflammatory mediators of endometriosis are similar with and without ovarian involvement.

Increase of activated mast cells in human endometriosis

PROBLEM

The proliferation of stromal cells in endometriosis promotes extensive adhesion; therefore, the morphological analysis of stromal lesions is important in the investigation of the pathogenesis of endometriosis.

METHOD OF STUDY

In this study, the morphological and numeric comparisons of degranulated mast cells were performed between endometriotic lesions and comparative regions (eutopic endometrium and normal uterine serosa) of patients with and without endometriosis.

RESULTS

In cases of endometriosis, diffuse infiltration of numerous mast cells was observed throughout the stromal lesions. These mast cells exhibited degranulation, and scattered granules were also observed. In the eutopic endometrium and normal uterine serosa of both the endometriosis patients and the controls, mast cells were rarely detected.

CONCLUSIONS

These results suggest that an abnormal immune response, specifically a hypersensitivity reaction, is strongly related to endometriosis; our findings will be helpful in the development of methods for the treatment of endometriosis.

Endometriosis and Inflammation in Infertility

A wealth of publications proposes that endometriosis and inflammation may have an unfavorable influence on fertility. A recent meta-analysis of assisted reproductive technologies demonstrated that, once confounding factors are controlled for, the pregnancy rate in women with endometriosis is approximately 50% of the rate of women with tubal factor infertility. Peritoneal fluid of women with endometriosis contains elevated amounts of macrophages and their secreted products, such as growth factors, cytokines, and angiogenic factors. Because reproductive organs are bathed in and thus will be influenced by peritoneal fluid, these proinflammatory mediators would affect various aspects of reproduction in women with endometriosis. Advanced stages of endometriosis may have easily understandable factors, such as distortion of the anatomy, causing infertility. On the other hand, in minimal or mild endometriosis mechanisms underlying reproductive failure are subtle and remain controversial. Recent reports suggest that inflammatory factors play a role in this endometriosis-associated reproductive failure. This review provides an overview of recent data on the effects of endometriosis-associated inflammation on fertility.

An evidence-based evaluation of endometriosis-associated infertility

Although endometriosis is associated with infertility, a clear causal relationship has yet to be established, unless adhesive disease is found. Despite this indirect association, multiple theories have been promulgated and studies are currently underway to investigate theoretic pathogenetic mechanisms. The data regarding the treatment of endometriosis-associated infertility are limited and conflicting; however, some general preliminary conclusions can be drawn. It seems that, with early-stage disease, surgical treatment increases pregnancy rates. Using the US Preventive Services Task Force classification scheme, the evidence in support of this finding is of the highest quality, or level I. Surgical treatment for moderate and severe disease also confers benefit, although the evidence in support of this treatment is of lesser quality, level II-3 by the scheme. Medical treatment, particularly if it induces an anovulatory state, has no benefit and may delay fertility. This evidence is again of the highest quality, with a classification of level I. Although assisted reproductive technologies are of benefit regarding fertility for women with endometriosis, the IVF evidence is inconclusive, with both treatments being evaluated by at least one randomized, controlled trial conferring a level I classification to the evidence. It is unclear at this time whether endometriomas have an impact on IVF outcome. The evidence consists of only a few lower-quality studies, with a classification level of II-2. Despite the haziness of current insight into the treatment of endometriosis-associated infertility, well-designed clinical trials and basic mechanistic investigations are underway in many reproductive medicine centers. As the data from these scientific inquiries emerge, clinicians will have a clearer view of effective treatment regimens for endometriosis.

Immunology and Endometriosis

PROBLEM

Accumulating data suggests that aberrant immune responses during retrograde menstruation may be involved in the development of endometriosis.

METHOD OF STUDY

The role of immunology in the etiology of endometriosis is reviewed and summarized from the available literature.

RESULTS

Immunologic factors may affect a woman's susceptibility to implantation of exfoliated endometrial cells. Immune alterations include increased number and activation of peritoneal macrophages, decreased T cell reactivity and natural killer cell cytotoxicity, increased circulating antibodies, and changes in the cytokine network.

CONCLUSION

There is substantial evidence that immunologic factors play a role in the pathogenesis of endometriosis and endometriosis-associated infertility. Decreased natural killer cell cytotoxicity leads to an increased likelihood of implantation of endometriotic tissue. In addition, macrophages and a complex network of locally produced cytokines modulate the growth and inflammatory behavior of ectopic endometrial implants.

Autoantibody responses to carbohydrate epitopes in endometriosis

Autoantibody responses to endometrial and serum antigens are a common feature of endometriosis. We have shown that the serum autoantibody response in endometriosis to a number of previously identified antigens, including alpha2-Heremans Schmidt glycoprotein and carbonic anhydrase, is specific for a carbohydrate epitope common to these proteins. Removal of carbohydrate moieties from these antigens resulted in a loss of antibody binding. Antibody reactivity was abolished following adsorption with the lectin jacalin, which specifically binds the Thomsen-Friedenreich (T) antigen (Gal beta1-3GalNAc). Demonstration that the autoantibodies also reacted with other Thomsen-Friedenreich antigen-bearing proteins, such as serum IgA1, hemopexin, and MMP-9, confirmed that this glycotope is involved in the autoantibody response. However, the autoantibody binding requires the presence of at least one sialic acid residue. Thus, the glycotope involved may be a sialylated T antigen. These findings allow us to hypothesize a number of mechanisms whereby the autoimmune response plays a direct role in several aspects of the disease process. The proposed mechanisms take into account the salient endocrine dependency of endometriotic lesions and other aspects of the disease process such as aberrant matrix metalloproteinase function and the ability of endometrial cells to implant at ectopic sites. The anti-T-like response may also be indicative of an underlying genetic defect in glycosylation or in the control of glycosylation by steroid sex hormones. Further characterization of this autoimmune response may prove useful in the development of serum-based diagnostic tests for endometriosis and may lead to the development of therapeutic strategies.

Embryotoxicity of peritoneal fluid in women with endometriosis. Its relation with cytokines and lymphocyte populations

BACKGROUND

The goals of the present work were to study the embryotoxic effects of peritoneal fluid (PF) in women with or without endometriosis, and to relate any embryotoxicity to the severity of endometriosis, infertility or achievement of pregnancy, cytokine concentrations and lymphocyte populations.

METHODS

Sixty-six consecutive women of reproductive age, 54 with endometriosis (21 infertile) and 12 infertile without endometriosis, and another 12 fertile women as control group, were included in this study. They all underwent laparoscopy or laparotomy in the second half of the cycle, and PF was collected from the pouch of Douglas. The embryotoxicity of the PF was assessed by means of a mouse embryo assay, and expressed as the number of embryos that did not reach blastocyst stage. Cytokines and lymphocyte populations present in PF were also studied and correlated with embryotoxicity.

RESULTS

PF embryotoxicity was increased in women with endometriosis, but there was little correlation with the severity of the disease. However, although a clear relationship to the presence of infertility was not found, embryotoxicity appeared to be lower in those infertile patients with endometriosis who later became pregnant. We found a significant increase in embryotoxicity in the presence of high cytokine concentrations, especially with interleukin-6, and less so with interleukin-8 (P < 0.05). No good correlation was observed with lymphocyte populations, but CD56 (NK) cells were significantly increased in the PF of women with endometriosis. In general, the correlations for embryotoxicity were better when PF was diluted at 20% (91.4 +/- 17 versus 68.1 +/- 31, P < 0.01).

CONCLUSIONS

These results suggest that alteration in the production of cytokines in the PF, especially IL-6, besides contributing to the endometriosis and its evolution, probably increases embryotoxicity. However, no correlation was found between the latter and associated infertility.

Role of cytokines in endometriosis

OBJECTIVE

To review the literature on the role of cytokines in the pathogenesis of endometriosis and endometriosis-associated infertility.

DESIGN

Pertinent studies were identified by a computer search of MEDLINE. References of selected articles were hand-searched for additional citations.

RESULT(S)

Recent studies suggest that the peritoneal fluid of women with endometriosis contains an increased number of activated macrophages that secrete various local products, such as growth factors and cytokines. Levels of several cytokines were reported to be elevated in the peritoneal fluid of women with endometriosis. Because the peritoneal environment may be controlled by locally regulated factors, cytokines are believed to play a role in the development and progression of endometriosis and endometriosis-associated infertility. A possible pathogenic mechanism links cytokines with endometriosis.

CONCLUSION(S)

Cytokines, which are produced by many cell types including endometriotic tissues, play diverse roles in the pathogenesis of endometriosis and endometriosis-associated infertility. More studies about the specific role of these cells and soluble factors are needed to improve understanding of endometriosis and to develop novel therapies.

Autoantibodies in endometriosis sera recognize a Thomsen-Friedenreich-like carbohydrate antigen

Autoantibody responses to endometrial antigens are a common feature of endometriosis. Antibody responses to a number of serum and tissue antigens such as alpha(2)-Heremans Schmidt glycoprotein (alpha(2)-HSG), transferrin, and carbonic anhydrase have been identified. The nature of the epitopes recognized on these proteins has not been determined. In this study we show that the serum antibody response to alpha(2)-HSG and carbonic anhydrase is against a common carbohydrate epitope which is also expressed on bovine fetuin. Removal of carbohydrate moieties from these antigens resulted in loss of antibody binding. Antibody reactivity with alpha(2)-HSG, fetuin and other antigens was removed by binding with the lectin jacalin. Jacalin specifically binds the Thomsen-Friedenreich antigen (Galbeta1-3GalNAc). Demonstrating that the autoantibodies also reacted with other Thomsen-Friedenreich antigen-bearing proteins, serum IgA1 and haemopexin confirmed an association with this epitope. These antigens have not been previously described as autoantigens in endometriosis and are of interest since they raise the possibility that this autoimmune response may either play a direct role in the disease process or reflect an abnormality of glycosylation in endometriosis. These results may also prove useful in the development of a serum diagnostic test for endometriosis.

Mouse embryo toxicity of IL-6 in peritoneal fluids from women with or without endometriosis

BACKGROUND

To determine whether there is a factor (or factors) in the peritoneal fluid of endometriosis patients that impairs embryo growth and embryo implantation.

METHODS

Growth and development of two-cell mouse embryos which were cultured in media with peritoneal fluid from women with or without endometriosis and interleukin-1-beta (IL-1beta), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha) levels in conditioned media were measured.

RESULTS

The blastocyst rate in the non-endometriosis group was 46.4 +/- 31.1%, and that of the endometriosis group was 54.6 +/- 28.7%. Logistic regression analysis using the criteria of blastocyst development in 454 embryos, showed that the peritoneal fluid from endometriosis could promote (p=0.015) but IL-6 could arrest embryo growth to blastocyst (p=0.025). IL-1beta and TNF-alpha levels had no significant effect on blastocyst formation.

CONCLUSION

Peritoneal fluid from women with endometriosis was not toxic to mouse embryo development. However, IL-6 in the peritoneal fluid deteriorated the growth and development of mouse embryos.

Tumour necrosis factor alpha concentrations in the peritoneal fluid of infertile women with minimal or mild endometriosis are lower in patients with red lesions only than in patients without red lesions

Tumour necrosis factor alpha (TNFalpha) of peritoneal fluid is believed to have important pro-inflammatory and angiogenic activities in the complex mechanisms of development of peritoneal endometriotic lesions. We have evaluated the concentrations of TNFalpha and macrophages in peritoneal fluid of infertile women with minimal or mild endometriosis and related them to the presence of peritoneal red lesions alone (red lesions only group; n = 11) or their absence (non-red lesions group; n = 36). A group of 39 infertile normo-ovulatory patients with normal pelvic anatomy was used as controls. TNFalpha concentrations did not differ between controls and either group of patients. Patients with red lesions only had significantly lower concentrations of TNFalpha in peritoneal fluid (P < 0.05) and had a higher proportion of samples with undetectable concentrations (P < 0.05) than patients without red lesions. The significant difference in TNFalpha concentrations was present when comparing the groups of patients in the proliferative phase but not in the secretory phase. Macrophage concentrations were not different in the groups. Our findings are compatible with an impairment of macrophage function and therefore lend support to the theory that an inappropriate immunological response of the peritoneal environment to regurgitated endometrium may play a part in the initial phases of endometriotic implants.

Induction of an angiogenic phenotype in endometriotic stromal cell cultures by interleukin-1beta

Activated peritoneal macrophages are associated with endometriosis and may play a central role in its aetiology by releasing interleukin-1beta (IL-1beta) in response to refluxed endometrium. Pari passu with the establishment of endometriotic implants is the development of a vascular supply. In this study we investigated the angiogenic properties of two endometrial proteins, vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6), and assessed their production in response to IL-1beta stimulation in human stromal cells isolated from normal endometrium (NE) and endometriotic lesions (EI). Proliferation of bovine brain capillary endothelial cells (BBCE) with a [(3)H]-thymidine incorporation assay was observed when VEGF (2.1 +/- 0.2-fold; P < 0.05) or VEGF and IL-6 (1.8 +/- 0.1-fold; P < 0.05) were added in vitro, relative to saline-treated control cultures. Northern blot analysis showed induction of VEGF mRNA (2.6-fold; P < 0.05) and IL-6 mRNA (6.3-fold; P < 0.05) transcripts in EI cells, but not NE cells, exposed to IL-1beta. A similar induction was seen with VEGF and IL-6 protein secretion in the responsive EI cells. Reverse transcription-polymerase chain reaction (RT-PCR) for the IL-1 receptor type I (IL-1 RI) indicated that the differential effects of IL-1beta on NE and EI cells was associated with 2.4 +/- 0.1-fold more receptor mRNA in EI versus NE cells. We propose that the ability of IL-1beta to activate an angiogenic phenotype in EI stromal cells but not in NE cells, is mediated by the IL-1 RI.

Importance of reactive oxygen species in the peritoneal fluid of women with endometriosis or idiopathic infertility

OBJECTIVE

To determine whether reactive oxygen species in peritoneal fluid might be a factor in infertility.

DESIGN

Prospective study.

SETTING

Andrology laboratory and gynecology clinic at a tertiary care facility.

PATIENT(S)

Women with endometriosis (n = 15) or idiopathic infertility (n = 11) who underwent laparoscopy for infertility. Patients undergoing tubal ligation served as controls (n = 13).

INTERVENTION(S)

Aspiration of peritoneal fluid.

MAIN OUTCOME MEASURE(S)

Reactive oxygen species levels, presence of polymorphonuclear granulocytes, and leukocyte distribution in peritoneal fluid.

RESULT(S)

Reactive oxygen species were present in the peritoneal fluid of patients with endometriosis, idiopathic infertility, and tubal ligation. Levels of reactive oxygen species did not show a statistically significant difference between patients with endometriosis and the control group in either unprocessed or processed (cell-free) peritoneal fluid, but did differ significantly between patients with idiopathic infertility and controls in processed peritoneal fluid. Polymorphonuclear granulocytes (> 1 x 10(6)/mL) were not present in the peritoneal fluid of any patient. Macrophage concentrations of peritoneal fluid did not differ significantly between controls and patients with endometriosis or idiopathic infertility.

CONCLUSION(S)

Reactive oxygen species in the peritoneal fluid may not affect fertility directly in women with endometriosis; however, they may have a role in patients with idiopathic infertility.

Pathophysiology. The biologic principles of disease

Endometriosis, although associated with a large variety of symptoms, primarily produces pain and infertility; however, the strong correlation with these disorders, along with basic questions as to why endometriosis develops, when does it become a disease status, and why it's associated with symptoms such as pain or infertility, are still not well understood. A better understanding of the relationship between disease and symptoms of endometriosis must be acquired if effective progress in the treatment of pain and infertility related to endometriosis is to be made.

Correlation of basal menses CA-125 levels and 6 month pregnancy rates in women undergoing treatments for infertility without assisted reproductive methods

PROBLEM

The objective of this study was to evaluate the correlation of menstrual CA-125 levels with pregnancy rates (PRs) after 6 months of treatment for infertility.

METHOD

The sample consisted of a heterogenous group of 160 women who sought treatment for infertility. Treatments include progesterone supplementation, donor insemination, intrauterine insemination, and ovulation induction therapy. No laparoscopies were done during the study period. A baseline CA-125 level was drawn during menses before the initiation of therapy. Patients were followed for 6 months of treatment or until a pregnancy was achieved.

RESULTS

There was no difference in the 6 month PR or viable PR by CA-125 level.

CONCLUSIONS

Elevated CA-125 levels are not predictive of poor fertility potential at least during the first 6 months of infertility therapy. Even though these higher levels sometimes suggest that endometriosis is present, the data suggest that correction of male factor, cervical factor or ovulation factor provides effective PRs without the need for laparoscopic intervention.

IL-1 beta, TNF-alpha, and IL-2 in peritoneal fluid and macrophage-conditioned media of women with endometriosis

PROBLEM

The presence of various cytokines in human peritoneal fluid has been incompletely evaluated. Changes in cytokine levels may be related to the development of endometriosis, infertility, and activation of peritoneal macrophages. This study assesses levels of IL-1 beta, IL-2 and TNF- alpha in peritoneal fluid and macrophage conditioned media of women with endometriosis.

METHOD

Peritoneal fluid was collected from 51 women at the time of diagnostic or operative laparoscopy for benign gynecologic disease. Peritoneal macrophages were isolated, cultured for 24 h, and the culture media collected. IL-1 beta, IL-2, and TNF- alpha levels were determined by commercial ELISA kits.

RESULTS

The mean concentration of IL-1 beta and TNF- alpha was significantly higher in macrophage conditioned media of patients with endometriosis (P < 0.02). However, there were no significant changes in peritoneal fluid cytokine levels. Peritoneal macrophage concentrations were also higher in patients with endometriosis.

CONCLUSION

This study supports the concept that endometriosis is associated with activation of peritoneal macrophages, and a higher concentration of these cells. This activation is reflected by the increased levels of cytokines found in macrophage conditioned media. The absence of significant changes in peritoneal fluid cytokine levels would seen to indicate that the above derangements are not responsible for the development or progression of endometriosis.

Evaluation of serum-associated embryotoxicity in women with reproductive disorders

PURPOSE

Our purpose was to determine whether some cases of infertility may be due to serological factors inhibiting development of the embryo.

METHOD

We examined the effect of infertile women's sera on the expansion, attachment, and spreading of mouse blastocysts in culture. Cell marker expression was also assayed by an indirect immunofluorescence technique. Serum samples from 75 infertile women were compared to the effect of 24 control AB sera.

RESULTS

After 72 hr, blastocyst spreading was significantly different depending on whether cultured in sera from women with unexplained infertility, anovulatory infertility, diethylstilbesterol exposure or controls. Neither sera from women with mechanical infertility (14) nor sera from women with endometriosis (8) affected blastocyst growth in culture.

CONCLUSIONS

Inhibitory sera were capable of reducing cytokeratin expression but had no effect on placental alkaline phosphatase or concanavalin A expression by blastocyst cells. It can be inferred that the inhibitory effect of sera from women with certain types of infertility might be due to damage to the cytoskeleton. This in vitro assay may predict the success or failure of IVF.

Monocyte-mediated enhancement of endometrial cell proliferation in women with endometriosis

OBJECTIVE

To investigate the capacity of monocytes from women with endometriosis to influence endometrial cell proliferation.

DESIGN

Uterine endometrial cells were cultured in the presence and absence of autologous blood monocytes for 72 hours before assessment of endometrial cell proliferation by thymidine incorporation.

SETTING

Patients were tested at initial presentation for evaluation of infertility and/or endometriosis.

PATIENTS, PARTICIPANTS

Fertile controls, n = 17; infertile controls, n = 9; untreated endometriosis, n = 29.

INTERVENTIONS

None.

RESULTS

Endometrial cell proliferation was enhanced significantly by blood monocytes in patients with endometriosis but was suppressed significantly by blood monocytes in fertile controls. Endometrial cell proliferation was not affected significantly by blood monocytes in infertile controls analyzed as a group, but a subset of infertile patients also showed enhancement of endometrial cell proliferation by blood monocytes.

CONCLUSIONS

Blood monocytes from patients with endometriosis and a subset of patients with unexplained infertility enhance autologous endometrial cell proliferation, whereas blood monocytes from fertile patients suppress endometrial cell proliferation. The capacity of monocytes to enhance endometrial cell proliferation appears to require both monocyte-derived factors that stimulate endometrial cell proliferation and endometrial cells capable of responding to those stimulatory factors. If either of these factors is absent, monocytes either suppress or have no effect on endometrial cell proliferation.

Cytokines in the peritoneal fluid of patients with endometriosis

OBJECTIVE

To determine which of the various cytokines interleukin-5 (IL-5), interleukin-6 (IL-6) and interleukin-1 (IL-1) are important in endometriosis.

METHODS

Peritoneal fluid (PF) samples were taken from 55 women at the time of either laparotomy or laparoscopy, and were examined for the levels of IL-5, IL-6 and IL-1 using each cytokine specific sandwich enzyme-linked immunosorbent assay. Thirty-two patients had pelvic endometriosis, eight post-pelvic inflammatory disease, four advanced cancer, three adenomyosis, three benign ovarian tumor, and other diseases. Statistical analysis was performed with the Mann Whitney test, chi-square test or Fisher's test.

RESULTS

Both IL-5 and IL-6 levels in PF specimens with endometriosis tended to be higher than normal, while the same specimens were mostly interleukin-1 beta (IL-1 beta) negative. Of great interest was the negative correlation between log (IL-5) and IL-6 (Fisher's test, P < 0.04).

CONCLUSION

These findings support the concept that IL-5 and IL-6 but not IL-1 are associated with endometriosis.

Adverse effects on sperm movement characteristics in women with minimal and mild endometriosis

OBJECTIVE

To test the effect of peritoneal fluid from infertile women with minimal or mild endometriosis on sperm movement characteristics in comparison with fertile and infertile women with no endometriosis.

DESIGN

A prospective observer-blind trial.

SETTING

Academic infertility department.

SUBJECTS

57 women undergoing diagnostic laparoscopy or laparoscopic sterilisation.

MAIN OUTCOME MEASURES

Changes in sperm movement characteristics in semen samples provided during routine infertility investigation or from sperm donors. Computer assisted semen analysis (CASA) performed using a Celltrack-S system.

RESULTS

Significant reductions in linearity (P < 0.05), amplitude of lateral head displacement (P < 0.01), straight line velocity (P < 0.01), and curvilinear velocity (P < 0.01) (but not percentage motility) were observed.

CONCLUSIONS

Peritoneal fluid from women with minimal or mild endometriosis adversely effects sperm movement characteristics in comparison to fertile women.

The natural killer activity of peritoneal fluid lymphocytes is decreased in women with endometriosis

OBJECTIVE

To investigate the local natural killer (NK) activity of the peritoneal fluid mononuclear cells (PFMC). DESIGN PATIENTS: In a prospective way, the NK activity (K562-assay) was measured in peripheral blood (PB) and peritoneal fluid (PF) of 44 women who underwent a laparoscopy for infertility and/or pain at the University Hospital of Gasthuisberg, Leuven, Belgium.

MAIN OUTCOME MEASURE

The NK activity of peripheral blood mononuclear cells and PFMC, the number and concentration of PFMC, the percentage of lymphocytes versus macrophages by May-Grünwald-Giemsa staining and the estradiol and progesterone concentration of the PF were correlated together and with the severity of endometriosis.

RESULTS

We demonstrated that there is a significant NK activity in PF and that this activity is decreased in women with endometriosis. This defect was more pronounced in the follicular phase of the cycle compared with the postovulatory phase. In PB of the same 44 women, the decreased NK activity correlated with the severity of the disease. This confirms our previous report on another 34 women.

CONCLUSIONS

The NK activity is decreased in women with endometriosis and correlated significantly with the severity of the disease in both the PB and PF of women with endometriosis.

Comparison of cytokine levels and embryo toxicity in peritoneal fluid in infertile women with untreated or treated endometriosis

OBJECTIVE

Our aim was to examine the relationship between the levels of cytokines in peritoneal fluid and its embryo toxicity.

STUDY DESIGN

The levels of interleukin-1 and tumor necrosis factor were measured in peritoneal fluid from infertile women who did not have endometriosis (n = 21), who had untreated endometriosis (n = 19), and who had undergone medical treatment for endometriosis (n = 10). Embryo toxicity was investigated in mouse two-cell embryos cocultured with the oviducts in culture media that contained various concentrations of peritoneal fluid.

RESULTS

The levels of cytokines were significantly higher in the peritoneal fluid from women who had untreated endometriosis than in women who did not have endometriosis, but they were extremely low in women who had undergone medical treatment with either danazol or buserelin. The peritoneal fluid from women who had untreated endometriosis adversely affected the cleavage of mouse two-cell embryos. After medical treatment the embryo toxicity of the peritoneal fluid was almost undetectable.

CONCLUSION

These results offer some theoretic bases in support of medical treatment to improve reproductive performance in infertile women who have endometriosis.

Expression of interleukin-1 (IL-1) beta messenger ribonucleic acid (mRNA) and IL-1 receptor antagonist mRNA in peritoneal macrophages from patients with endometriosis

OBJECTIVE

To investigate the expression of interleukin-1 (IL-1) beta messenger ribonucleic acid (mRNA) and IL-1 receptor antagonist (IL-1ra) mRNA in peritoneal macrophages.

DESIGN, SETTING

Peritoneal fluid (PF) samples were collected from patients who underwent laparoscopy or laparotomy. Northern blot analysis was performed at the reproductive research laboratory.

PATIENTS

Twenty-six patients with endometriosis, 10 patients with postinflammatory pelvic adhesion, and 12 control women with normal pelvis.

MAIN OUTCOME MEASURE

Polyadenylated RNA isolated from peritoneal macrophages was analyzed on Northern blots by using synthetic oligonucleotide probes.

RESULTS

The level of IL-1 beta mRNA expression was elevated in the group with stage I endometriosis, whereas the increased expression of IL-1ra mRNA was observed in the group with stages III and IV endometriosis. The level of IL-1 beta mRNA showed a positive correlation with that of IL-1 beta in PF and a negative correlation with the level of IL-1ra mRNA.

CONCLUSIONS

Our results suggest that peritoneal macrophages express IL-1ra mRNA rather than IL-1 beta mRNA with the progress of endometriosis and that peritoneal macrophages may secrete IL-1ra protein that modulates the effects of IL-1.

The effect of preovulatory peritoneal fluid from cases of endometriosis on murine in vitro fertilization, embryo development, oviduct transport, and implantation

OBJECTIVE

The null hypothesis of our study is that the success of in vitro and in vivo murine fertilization and embryo development is not decreased by gamete exposure to peritoneal fluid from superovulated patients with endometriosis.

STUDY DESIGN

A murine in vitro fertilization model was used to test the effects of endometriosis versus nonendometriosis peritoneal fluid at concentrations of 1%, 5%, and 10% versus an unsupplemented control. Fertilization and blastocyst formation were compared by analysis of variance. In a second experiment superovulated mice were given intraperitoneal injections of endometriosis or nonendometriosis fluid or saline solution 8 hours after human chorionic gonadotropin and then mated. Some mice were killed 3 days after coitus to assess embryo number, cleavage stage, and uterine versus tubal position by means of analysis of variance and covariance with repeated measures. Others were killed 12 days after coitus with the mean number of implantations per animal between groups compared by Student's t test.

RESULTS

In vitro fertilization rates decreased as peritoneal fluid concentration increased in both the endometriosis (65%, 43%, 33%) and nonendometriosis (65%, 52%, 35%) groups at 1%, 5%, and 10% peritoneal fluid concentration, respectively. Mice receiving intraperitoneal endometriosis or nonendometriosis fluid or saline solution injections showed no differences in embryo number, cleavage, uterine versus tubal position, or mean implantation number.

CONCLUSION

Peritoneal fluid from superovulated patients had no differentially negative effect when compared with the effect of nonendometriosis peritoneal fluid on murine in vitro or in vivo fertilization and embryo development, tubal embryo transport, or implantation.

Peritoneal fluid interleukin-1 beta and tumor necrosis factor in patients with benign gynecologic disease

The levels of interleukin 1 beta (IL-1 beta) and tumor necrosis factor (TNF) in peritoneal fluid (PF-IL-1 beta and PF-TNF) and production of IL-1 beta and TNF by peritoneal macrophages were determined in patients with benign gynecologic disease. The level of PF-IL-1 beta was elevated in the acute pelvic inflammatory disease (PID) and stages I and II endometriosis (E I/II) groups compared with the normal pelvis group, but not in the myoma of the uterus, ovarian cyst, and postinflammatory pelvic adhesion groups. The level of PF-TNF was elevated in the PID, EI/II and stages III and IV endometriosis (EIII/IV) groups. There was no correlation between the levels of PF-IL-1 beta and PF-TNF. Neither the level of PF-IL-1 beta nor that of PF-TNF was correlated with the concentration of peritoneal macrophages. Peritoneal macrophages produced IL-1 beta and TNF in vitro in the absence of stimulants. The levels of PF-IL-1 beta and PF-TNF are presumably linked to the activation of peritoneal macrophages.

Absence of a direct effect of recombinant tumor necrosis factor-alpha on human sperm function and murine preimplantation development

OBJECTIVE

This study was designed to test the in vitro effects of human recombinant tumor necrosis factor (rTNF) on sperm motility, fertilization, and preimplantation development.

DESIGN

A sensitive enzyme immunoassay was used to determine half-lives of rTNF and confirm concentrations of cytokine throughout experimental conditions. Effect of rTNF on human sperm survival was measured by computer-assisted methodology, and effect on human sperm penetration was assessed by hamster ova penetration. Cytokine effect on murine gamete interaction was determined by in vitro fertilization (IVF). Murine preimplantation development was assessed by in vitro development of cryopreserved-thawed one-cell zygotes.

RESULTS

The half-life of rTNF was reduced by the addition of sperm to culture media (P less than 0.001). Sperm motility (P = 0.245) and hamster ova penetration (P = 0.62) were not altered by incubations in the presence of concentrations of rTNF up to 10,000 U/mL. Mouse IVF (P = 0.60) and preimplantation development (P = 0.56) were not altered by rTNF in concentrations up to 5,000 U/mL.

CONCLUSIONS

These results demonstrate rTNF by itself does not interfere with gamete function or early embryo development.

Role of peritoneal inflammation in endometriosis-associated infertility

This paper has discussed the evidence for the presence of infertility in patients with endometriosis and more critically reviewed some of the studies that have addressed the impact of various potential local peritoneal mechanisms that may lead to subfertility. Substantial evidence supports the notion that patients with endometriosis have reduced fecundability. Although several mechanisms, including, e.g., anatomic factors and ovulatory dysfunction, are possible, recent studies have pointed towards local inflammatory cells and their secretory products as being important mediators of subfertility. Ample evidence exists for the presence of an altered peritoneal inflammatory environment in patients with endometriosis. In addition, in vitro studies have identified peritoneal macrophages and their secretory products, specifically TNF-alpha as the most likely contributors to the reduced fecundability through effects on sperm function.

Endometrial epithelial cells in peritoneal fluid during the early follicular phase

Peritoneal fluid (PF) was obtained during the early follicular phase in 24 women at laparoscopy as part of infertility investigation. The cells present in PF were pelleted and cultured. Developing endometrial epithelial cell colonies were identified in 19 women (79%). Identification of these cell colonies was facilitated using the monoclonal antibody BW 495/36 as specific marker. The number of endometrial epithelial cell colonies showed a large variation (1 to 200 or more PF sample). No significant distinction in incidence and number of cell colonies was found between women with minimal (n = 11) and without endometriosis (n = 12). A significant correlation with number of cell colonies was found in women with infertility and no mechanical and male infertility factors. These data indicate that retrograde transport of viable endometrial cells during menstruation occurs in most women with patent tubes. Implications of the results for the relation between retrograde menstruation, endometriosis, and infertility are discussed.

Endometriosis and infertility

The relationship of endometriosis, the most common benign gynaecological disease during reproductive life, to infertility is generally ill understood. The association between infertility and minimal to mild endometriosis, when no anatomical defect is evident, may be explained by the following possible mechanisms: alternations in peritoneal fluid (macrophages - immunoglobulins, Interleukin-1, protease inhibitors, prostanoids, an ovum capture inhibitor), ovulatory dysfunctions (anovulation, LUF syndrome), luteal phase defect, disturbed implantation, and spontaneous abortion. These possibilities are discussed. The latest prospective controlled studies offer strong evidence that endometriosis per se is not a direct cause of infertility. On the other hand, the disease usually deteriorates if not treated, and therefore medical or surgical interventions are often needed when expectant treatment or other infertility therapies, e.g., ovulation induction, fail to result in pregnancy. Women with minimal to mild endometriosis only should be diagnosed as having unexplained infertility, which today may be treated by in vitro fertilization.

Lymphocyte activity in the presence of peritoneal fluid from fertile women and infertile women with and without endometriosis

Peritoneal fluid from women with endometriosis, unexplained infertility, and fertile controls were compared to one another and to normal human serum for effects on lymphocyte proliferation in vitro. Peritoneal fluid samples were also assayed for both interleukin-1 and interleukin-2. All peritoneal fluid samples significantly enhanced lymphocyte proliferation in both mitogen-stimulated and unstimulated cultures compared with serum controls. Mitogen-induced leukocyte proliferation was higher in the presence of peritoneal fluid from women with endometriosis compared with other samples. Five out of 23 samples from endometriosis patients contained elevated levels of interleukin-1 and three out of 23 contained elevated levels of interleukin-2. Six out of eight peritoneal fluid samples from unexplained infertility patients also had elevated levels of interleukin-2; samples from fertile women did not contain elevated levels of either cytokine. Our data indicate that peritoneal fluid from women with endometriosis and unexplained infertility support the activation and proliferation of lymphocytes. Leukocyte products may locally affect the progression of disease and fertility.

Reduction of the intraperitoneal inflammation associated with endometriosis by treatment with medroxyprogesterone acetate

An intraperitoneal inflammatory exudate has been repeatedly observed in infertile women without mechanical compromise of the pelvic viscera, particularly with endometriosis. This is manifested by increases in the peritoneal fluid volume, leukocyte number, and proteolytic enzyme concentrations. We tested the hypothesis that the stimulus responsible for eliciting this intraperitoneal inflammation is retrograde menstruation by measuring the peritoneal fluid volume and leukocyte count in 16 infertile women with endometriosis before and after ovulation suppression with medroxyprogesterone acetate, 30 mg/day for 4 months. Medroxyprogesterone acetate therapy significantly reduced the peritoneal fluid volume (22.5 +/- 4.1 versus 6.8 +/- 0.9 ml mean +/- SE, p less than 0.0001), the peritoneal fluid leukocyte count (30.7 +/- 6.5 versus 7.1 +/- 0.7 x 10(6) cells per patient, p less than 0.0001), and American Fertility Society score (23.2 +/- 5.1 versus 15.4 +/- 4.1, p less than 0.0002). We conclude that medroxyprogesterone acetate treatment reduces the intraperitoneal exudate associated with endometriosis. These results support the contention that the stimulus eliciting the intraperitoneal inflammation in infertile women with endometriosis is retrograde menstruation.