Hormonal profiles and embryo quality in women with severe endometriosis treated by in vitro fertilization and embryo transfer

The Effects of Endometriosis on Ovarian Functions

Infertility is a main manifestation of endometriosis, though the exact pathogenesis of endometriosis-associated infertility remains unclear. Compromised ovarian functions may be one of the causes of endometriosis related infertility. The ovarian function can be classified into three basic elements, (1) production of ovarian hormones, (2) maintenance of follicular development until ovulation, and (3) reservoir of dormant oocytes (ovarian reserve). The effects of endometriosis on ovarian hormone production and follicular development are inconclusive. Ovarian endometrioma is common phonotype of endometriosis. Development of endometrioma per se may affect ovarian reserve. Surgery for endometriomas further diminish ovarian reserve, especially women with bilateral involvement. Early intervention with surgery and/or medical treatment may be beneficial, though firm evidence is lacking. When surgery is chosen in women at reproductive age, specific techniques that spare ovarian function should be considered.

Endometrial causes of recurrent pregnancy losses: endometriosis, adenomyosis, and chronic endometritis

Chronic inflammatory processes affecting the endometrium, as encountered in endometriosis, adenomyosis, and chronic endometritis, alter endometrial receptivity. These disorders are associated with early pregnancy losses and possibly recurrent pregnancy losses (RPL). In the cases of endometriosis, other factors associated with the disease also are susceptible of causing miscarriages and possibly RPL, such as an impact of intrapelvic inflammatory processes affecting the oocyte and embryo in case of natural conception. Conversely these latter effects obviously are bypassed in case of assisted reproductive technology. Chronic inflammation of the endometrium in the condition known as chronic endometritis also causes early pregnancy losses and RPL with beneficial effects achieved when specific treatment is undertaken.

Endometriosis reduces ovarian response in controlled ovarian hyperstimulation independent of AMH, AFC, and women's age measured by follicular output rate (FORT) and number of oocytes retrieved

PURPOSE

To determine the influence of endometriosis on the ovarian response during controlled ovarian hyperstimulation measured by number of oocytes retrieved and the follicular output rate (FORT).

METHODS

A retrospective, single center study included 96 women, who underwent ICSI treatments for male factor infertility according to World Health Organisation between 2016 until 2018. A total of 96 patients were included in the study with 205 fresh ICSI cycles. The study group included 26 patients with endometriosis after surgical and medical treatment; the control group included 70 patients without endometriosis. The women with endometriosis underwent 47 and the control group 158 ICSI cycles. Women underwent fresh intracytoplasmatic sperm injection cycles after controlled ovarian hyperstimulation following a GnRH-antagonist protocol. The FORT was calculated as the ratio of pre-ovulatory follicle count × 100/small antral follicle count at baseline.

RESULTS

A lower number of retrieved oocytes (5.89 vs. 7.25, p = 0.045), lower FORT (75.67 vs. 94.63, p = 0.046), lower number of metaphase II oocytes (4.87 vs. 6.04, p = 0.046), and lower fertilization rate after intracytoplasmatic sperm injection (40.61 vs. 57.76, p = 0.003) were found in women with endometriosis compared to women without endometriosis. The number of oocyctes retrieved was 0.71 lower in the group with endometriosis than in the group without (p = 0.026). The FORT was 24.55% lower in the group with endometriosis (p = 0.025).

CONCLUSIONS

Endometriosis reduces the FORT and the number of metaphase-II oocytes after controlled ovarian hyperstimulation independly of women's age, antral follicle count and anti-Müllerian hormone.

Patients with endometriosis have aneuploidy rates equivalent to their age-matched peers in the in vitro fertilization population

OBJECTIVE

To determine whether endometriosis ultimately results in an increased risk of embryonic aneuploidy.

DESIGN

Retrospective cohort.

SETTING

Infertility clinic.

PATIENT(S)

Patients participating in an in vitro fertilization (IVF) cycle from 2009-2015 using preimplantation genetic screening (PGS) who had endometriosis identified by surgical diagnosis or by ultrasound findings consistent with a persistent space-occupying disease whose sonographic appearance was consistent with endometriosis.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Rate of aneuploidy in endometriosis patients undergoing IVF compared to controls without endometriosis undergoing IVF.

RESULT(S)

There were 305 patients with endometriosis who produced 1,880 blastocysts that met the criteria for inclusion in the endometriosis group. The mean age of the patients with endometriosis was 36.1 ± 3.9 years. When the aneuploidy rates in patients with endometriosis and aneuploidy rates in patients without endometriosis were stratified by Society for Assisted Reproductive Technology age groups and compared, there were no statistically significant differences in the rate of aneuploidy (odds ratio 0.85; 95% confidence interval, 0.84-0.85).

CONCLUSION(S)

Patients with endometriosis undergoing IVF have aneuploidy rates equivalent to their age-matched peers in IVF population who do not have endometriosis.

Impact of endometriosis and its staging on assisted reproduction outcome: systematic review and meta-analysis

OBJECTIVE

To evaluate whether the presence or severity of endometriosis affects the outcome of assisted reproductive techniques (ART).

METHODS

In this systematic review, all studies comparing the outcome of ART in women with and those without endometriosis, or at different stages of the disease, were considered eligible. We used either risk ratio (RR) or mean difference (MD) and their 95%CIs for comparisons. The primary outcome was live birth; the secondary outcome was clinical pregnancy. Miscarriage and the number of oocytes retrieved were examined as additional outcomes.

RESULTS

We included 92 studies in the review and 78 in the meta-analysis: 20,167 women with endometriosis were compared with 121,931 women without endometriosis, and 1703 women with Stage-III/IV endometriosis were compared with 2227 women with Stage-I/II endometriosis. The following results were observed for the comparison of women with endometriosis vs women without endometriosis: live birth, RR = 0.99 (95%CI, 0.92-1.06); clinical pregnancy, RR = 0.95 (95%CI, 0.89-1.02); miscarriage, RR = 1.31 (95%CI, 1.07-1.59); number of oocytes retrieved, MD = -1.56 (95%CI, -2.05 to -1.08). The following results were observed for the comparison of women with Stage-III/IV vs Stage-I/II endometriosis: live birth, RR = 0.94 (95%CI, 0.80-1.11); clinical pregnancy, RR = 0.90 (95%CI, 0.82-1.00); miscarriage, RR = 0.99 (95%CI, 0.73-1.36); number of oocytes retrieved, MD = -1.03 (95%CI, -1.67 to -0.39).

CONCLUSIONS

Women with endometriosis undergoing ART have practically the same chance of achieving clinical pregnancy and live birth as do women with other causes of infertility. No relevant difference was observed in the chance of achieving clinical pregnancy and live birth following ART when comparing Stage-III/IV with Stage-I/II endometriosis. The quality of the evidence for the additional examined outcomes was very low, not allowing meaningful conclusions to be drawn.

The effect of endometriosis on in vitro fertilisation outcome: a systematic review and meta-analysis

BACKGROUND

Endometriosis is found in 0.5-5% of fertile women and 25-40% of infertile women. It is known that endometriosis is associated with infertility, but there is uncertainty whether women with endometriosis have adverse pregnancy outcomes in in vitro fertilisation (IVF) treatment.

OBJECTIVES

To explore the association between endometriosis and IVF outcome.

SEARCH STRATEGY

Searches were conducted on MEDLINE, EMBASE, Cochrane Library and Web of Science (inception, December 2012) in all languages, together with reference lists of retrieved papers.

SELECTION CRITERIA

Studies comparing IVF outcome in women with endometriosis with women without endometriosis. Patients were classified by stage of endometriosis. The outcomes were fertilisation, implantation, clinical pregnancy and live birth rates. Study selection was conducted independently by two reviewers. The Newcastle-Ottawa Quality Assessment Scale was used for quality assessment.

DATA COLLECTION AND ANALYSIS

Data extraction was conducted independently by two reviewers. Relative risks from individual studies were meta-analysed.

MAIN RESULTS

Twenty-seven observational studies were included, comprising 8984 women. Meta-analysis of these studies showed that fertilisation rates were reduced in stage I/II of endometriosis (relative risk [RR] = 0.93, 95% confidence interval [95% CI] 0.87-0.99, P = 0.03). There was a decrease in the implantation rate (RR = 0.79, 95% CI 0.67-0.93, P = 0.006) and clinical pregnancy rate (RR = 0.79, 95% CI 0.69-0.91, P = 0.0008) in women with stage III/IV endometriosis undergoing IVF treatment.

CONCLUSION

The presence of severe endometriosis (stage III/IV) is associated with poor implantation and clinical pregnancy rates in women undergoing IVF treatment.

Women with advanced-stage endometriosis and previous surgery respond less well to gonadotropin stimulation, but have similar IVF implantation and delivery rates compared with women with tubal factor infertility

OBJECTIVE

To investigate the response to controlled ovarian hyperstimulation and ART outcomes in women with advanced-stage endometriosis and previous surgeries at the Yale IVF program between 1996 and 2002.

DESIGN

Retrospective case control study.

SETTING

Academic medical center.

PATIENT(S)

The study group consisted of 68 women who previously undergone laparoscopic surgery for advanced-stage endometriosis. The control group included 106 women with tubal-factor infertility. The women with endometriosis underwent 133 IVF-ET cycles and the control group 208 cycles.

INTERVENTION(S)

Controlled ovarian hyperstimulation and IVF-ET.

MAIN OUTCOME MEASURE(S)

Response to gonadotropins, fertilization, cleavage, implantation, pregnancy, miscarriage, and live birth rates.

RESULT(S)

Lower peak E(2) levels, higher total gonadotropin requirements, lower oocyte yield, and higher cancellation rates were found in women with endometriosis compared with tubal-factor control subjects. However, no differences were found in fertilization, cleavage, implantation, pregnancy, miscarriage, and delivery rates between the endometriosis and tubal-factor groups.

CONCLUSION(S)

Women with advanced-stage endometriosis who have undergone previous surgery respond less well to gonadotropins than women with tubal-factor infertility. However, implantation, pregnancy, and delivery rates are similar, suggesting that embryo quality and uterine receptivity remains unaffected despite diminished ovarian reserve in women with 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.

Endometrial leptin and leptin receptor expression in women with severe/moderate endometriosis

The leptin system has been implicated in reproductive function, acting at endocrine and paracrine levels. Recently, deregulation of this gene family has been linked to endometrial changes caused by endometriosis. In the present study, we compare the expression of leptin receptor mRNA during the pre-receptive (LH+2) and receptive (LH+9) phases in the eutopic endometrium from patients with severe/moderate endometriosis (n = 30) versus fertile controls (n = 12). In each patient, two endometrial samples were obtained at LH+2 and LH+9 in their natural cycles. When real-time quantitative fluorescent PCR was performed, an up-regulation of OB-RL and all the isoforms investigated was observed at LH+9 versus LH+2 in patients with and without endometriosis. However, no difference was found in the expression pattern of the total leptin receptor OB-RT, or in its long OB-RL and soluble HuB219.3 forms when the eutopic endometria of patients with severe/moderate endometriosis and fertile controls were compared. By means of in situ hybridization, total leptin receptor mRNA was localized in the luminal epithelium and the glands of the endometrium. The immunohistochemical analysis of the long form of leptin receptor was also performed in order to confirm these findings at the protein level. Finally, we have also shown similar leptin mRNA expression in both the control group and patients with endometriosis. In conclusion, we have not identified differences in the endometrial expression and localization of leptin and the leptin receptor when comparing the eutopic endometrium of women with severe/moderate endometriosis and fertile controls.

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.

Ovarian endometriosis: from pathogenesis to surgical treatment

PURPOSE OF REVIEW

This review analyzes the literature on ovarian endometrioma, examining the controversies on pathogenesis, malignant transformation and surgical therapy.

RECENT FINDINGS

Recent literature reflects the necessity of clearly defining the ethiologic and pathologic factors that determine the origin of ovarian endometriosis and explain the increase in the condition with the prospect of developing effective prevention therapy. The possibility that ovarian endometriomas undergo malignant transformation is widely reported in the literature. Recent studies underline the importance of detecting histological differences in endometriosis (hyperplasia and atypia) and several studies of molecular biology support the theory of genetic alterations interfering with malignant transformation of ovarian endometriosis.

SUMMARY

The surgical approach must take into account all this information and, when the therapy is conservative, complete excision of the disease must be laparoscopically performed without affecting the healthy ovarian tissue.

Effect of endometriosis on in vitro fertilization

OBJECTIVE

To investigate the IVF outcome for patients with endometriosis.

DESIGN

Meta-analysis.

SETTING

Academic research center.

PATIENT(S)

A MEDLINE search and review of the literature were performed. Patients were classified by level of endometriosis, and controls were classified according to the indication for IVF.

INTERVENTION(S)

Bivariate analysis and multivariate logistic regression was used to estimate overall effect and control for confounding.

MAIN OUTCOME MEASURE(S)

Pregnancy rates, fertilization rate, implantation rates, and numbers of oocytes retrieved.

RESULT(S)

Twenty-two published studies were included in the overall analysis. The chance of achieving pregnancy was significantly lower for endometriosis patients (odds ratio, 0.56; 95% confidence interval, 0.44-0.70) when compared with tubal factor controls. Multivariate analysis also demonstrated a decrease in fertilization and implantation rates, and a significant decrease in the number of oocytes retrieved for endometriosis patients. Pregnancy rates for women with severe endometriosis were significantly lower than for women with mild disease (odds ratio, 0.60; 95% confidence interval, 0.42-0.87).

CONCLUSION(S)

Patients with endometriosis-associated infertility undergoing IVF respond with significantly decreased levels of all markers of reproductive process, resulting in a pregnancy rate that is almost one half that of women with other indications for IVF. These data suggest that the effect of endometriosis is not exclusively on the receptivity of the endometrium but also on the development of the oocyte and embryo.

Endometriosis and infertility: the debate continues

A causal relationship between minor endometriosis and infertility or subfertility has not yet been demonstrated, although a significant association is shown by prevalence studies. This article critically reviews the evidence for pituitary-ovarian dysfunction as a cause for subfertility in women with minor endometriosis. The lack of fertile controls with endometriosis presents a methodological problem. Group comparison in studies using tubal infertility cases as controls has demonstrated impaired follicular growth, reduced circulating oestradiol concentrations during the preovulatory phase and oestradiol and progesterone during the early luteal phase, and disturbed luteinizing hormone (LH) surge patterns. LH concentration in preovulatory follicular fluid is also reduced, and granulosa cells collected at the same time have impaired steroidogenic capacity in vitro. However, these findings are not consistent in published studies. Significantly lower oocyte fertilization rates (49%) are found compared with controls (69%), even after maximum stimulation with exogenous follicle-stimulating hormone and human chorionic gonadotrophin (52% versus 69%). The implantation rate is also lower (11% versus 13%). An inherent disorder of follicular function seems likely, and LH surge impairment is probably a secondary effect. Impairment of oocyte fertilization would thus contribute substantially to the natural subfertility associated with endometriosis, but in vitro fertilization is still successful as excess numbers of oocytes are available.

Natural cycle IVF in unexplained, endometriosis-associated and tubal factor infertility

BACKGROUND

To elucidate possible differences between unexplained and minimal peritoneal endometriosis-associated infertility, we studied their outcome in natural cycle IVF (NIVF).

METHODS

A prospective cohort study was carried out on unexplained (33 couples), minimal peritoneal endometriosis-associated (30 couples) and tubal factor (24 couples) infertility in 223 NIVF cycles, using human chorionic gonadotrophin (HCG) for ovulation induction.

RESULTS

During the first NIVF attempt, follicular and luteal phase oestradiol, FSH, LH and progesterone concentrations, as well as endometrial thickness and follicular diameter were similar among the three groups. Periovulatory follicular growth monitored from day of HCG administration to oocyte aspiration was significantly lowered in unexplained infertility compared with minimal endometriosis-associated and tubal factor infertility. The fertilization rate, clinical pregnancy rate per initiated cycle, per successful oocyte retrieval and per embryo transfer, in minimal endometriosis (80.0, 10.4, 16.0 and 23.5% respectively) were similar to that in tubal factor infertility patients (68.6, 5.8, 11.4 and 16.0%) but significantly higher (P < 0.05) than that of the unexplained infertility group (62.2, 2.6, 5.4 and 8.7%).

CONCLUSIONS

The significant reduction in follicular periovulatory growth, fertilization and pregnancy rates in unexplained infertility compared with minimal peritoneal endometriosis patients may be explained by sub-optimal follicular development with possibly reduced oocyte quality, intrinsic embryo quality factors or by impaired implantation. From a clinical point of view, NIVF is less suited to unexplained infertility treatment, but might represent an interesting treatment option for minimal peritoneal endometriosis-associated infertility.

The presence and extent of endometriosis do not effect clinical pregnancy and implantation rates in patients undergoing intracytoplasmic sperm injection

OBJECTIVE

To assess the impact of endometriosis on the outcome of intracytoplasmic sperm injection (ICSI) outcome.

STUDY DESIGN

Retrospective case-control study which enrolled 1280 consecutive cycles of 834 couples of ICSI with ejaculated sperm. Among them, 973 cycles of 632 couples had resulted in embryo transfer (ET). The presence of endometriosis was noted in 110 consecutive cycles of 45 patients among which 78 cycles of 44 patients had resulted in ET. Data from endometriosis group were analyzed in subgroups of minimal-mild (49 ET cycles of 25 patients) and moderate-severe (29 ET cycles of 19 patients). The controls consisted of 1170 consecutive cycles of age-matched 771 couples. Of the controls, 588 couples had 895 cycles of ET. Main outcome measures were implantation and clinical pregnancy rates.

RESULTS

There were no differences in cycle and ET cancellation rates between control and endometriosis groups. The number of oocytes retrieved, fertilization and cleavage rates and the number and quality of embryos developed and transferred were similar among the groups. The implantation and clinical pregnancy rates were also comparable.

CONCLUSION

The presence and extent of endometriosis do not affect implantation and clinical pregnancy rates in patients undergoing ICSI.

Expression of leptin receptor in human endometrium and fluctuation during the menstrual cycle

Leptin is secreted by adipocytes and regulates appetite through interaction with hypothalamic leptin receptors (OB-R). Accumulated evidence shows that leptin is involved in the stimulation of reproductive functions and that local expression of leptin and OB-R in the ovary, oocyte, embryo, and placenta plays a role in early development. To investigate the role of leptin in implantation, we examined the expression of OB-R and leptin in the human endometrium. Northern and Western blot analyses and RT-PCR showed that the long form of OB-R (OB-R(L)) messenger ribonucleic acid (mRNA) and protein were expressed. In contrast, leptin mRNA or protein was not detected. All of the splice variants of OB-R (OB-R(T)) and OB-R(L) transcripts were expressed in 90% and 84% of the cases, respectively. OB-R mRNA expression peaked in the early secretory phase. Decidual tissue of early gestation also expressed OB-R(T) and OB-R(L). Their incidence and abundance were comparable among endometria with benign uterine diseases and disease-free endometria and were not related to a body mass index within the normal range. The present results indicate that OB-R, but not leptin, is expressed in the human endometrium.

Endometriosis and assisted reproductive technologies

The association between endometriosis and infertility is well established, and different mechanisms have been postulated to cause infertility depending on the stage of endometriosis. Controlled ovarian hyperstimulation improves pregnancy outcome for minimal to mild endometriosis; however, there are no randomized controlled studies of this technique in patients with severe disease. Further, ART appears to have an overall beneficial effect for all stages of endometriosis. Based on the current staging system, several studies have not been able to demonstrate a significant difference in true outcomes for different stages of the disease. The limitations of these studies have been discussed above. Similarly, the effect of endometriomas when considered independent of the stage is still unclear. In addition to ART, pretreatment with GnRH analogues or surgical intervention may be beneficial and needs to be addressed in randomized controlled studies. It is evident that we urgently need large randomized studies to answer several questions about the treatment of endometriosis-associated infertility with ART. Although our current practice is based primarily on retrospective observational studies and small randomized studies, the overall impact on pregnancy outcome is beneficial.

Effects of endometriomas on ooccyte quality, embryo quality, and pregnancy rates in in vitro fertilization cycles: a prospective, case-controlled study

PURPOSE

The effect of endometriomas on oocyte quality, embryo quality, and pregnancy rates in in vitro fertilization (IVF) cycles was evaluated.

METHODS

Forty-five women had "chocolate" cysts aspirated at the time of oocyte retrieval, and cyst fluid CA 125 levels were measured to ascertain presence of "true" endometriomas. Fifty-seven women without any complex cysts at the time of oocyte retrieval served as controls. IVF cycle outcome parameters were compared between the two groups.

RESULTS

Women with endometriomas experienced a significantly higher rate of early pregnancy loss compared to controls (47 vs 14%). There was also a trend toward fewer oocytes retrieved and fewer embryos reaching at least the four-cell stage 48 hr after retrieval in patients with true endometriomas vs controls.

CONCLUSIONS

The presence of endometriomas at the time of oocyte retrieval is associated with increased rates of early pregnancy losses. The number of oocytes retrieved and the embryo quality may also be affected adversely in the presence of endometriomas.

The effect of endometriosis on implantation: results from the Yale University in vitro fertilization and embryo transfer program

OBJECTIVE

To investigate the effect of endometriosis on implantation.

DESIGN

Case-control study from Yale University IVF-ET program.

PATIENTS

Two hundred eighty-four consecutive IVF cycles were analyzed retrospectively. Patients with endometriosis only (n = 35; 89 cycles) were compared with an age-matched control group with tubal infertility (n = 70; 147 cycles) and also to a group with unexplained infertility (n = 15; 48 cycles). Data from the endometriosis group was analyzed further in subgroups of minimal-mild (43 cycles) and moderate-severe (46 cycles).

RESULTS

No difference was found in the number and the quality of oocytes retrieved and fertilization rates between the endometriosis, the tubal infertility, and the unexplained infertility groups. The quality and the number of embryos transferred in each group were comparable. A trend toward reduced pregnancy rate per transfer (14.8%) in the endometriosis versus tubal or unexplained infertility groups (25.7% and 23.3%, respectively) was observed. Implantation rate (gestational sac per transferred embryo) was significantly lower in the endometriosis versus the tubal infertility group (3.9% versus 8.1%; unexplained infertility group, 7.2%). Analysis of first cycles only across all groups revealed that the implantation rate also was significantly lower in the endometriosis versus the tubal infertility group (3.1% versus 9%; unexplained infertility group, 6.7%). Within the endometriosis group, although the pregnancy rate per cycle and per transfer were similar in subgroups, patients with minimal-mild endometriosis had the lowest implantation rate.

CONCLUSION

We conclude that, in patients with endometriosis, implantation rate is low. Abnormal implantation, which may be secondary to endometrial dysfunction or embryotoxic environment, is a factor in endometriosis-associated subfertility.

Pretreatment with gonadotrophin releasing hormone (GnRH) analogue prior to in vitro fertilisation for patients with endometriosis

To assess the effect of GnRH pretreatment prior to IVF-ET on fertilisation and pregnancy rates in patients with endometriosis compared with tubal infertility, a retrospective analysis of 228 cycles of tubal infertility cases (Group 1) and 92 cycles of endometriosis has been performed. Patients with endometriosis were classified by the revised AFS scoring system to two groups: 37 cycles of minimal and mild endometriosis (Group 2) and 55 cycles of moderate and severe endometriosis (Group 3). The GnRH analogue buserelin was used for pituitary desensitisation in all IVF cycles. Endometriosis patients have a minimum of 6 weeks GnRH treatment prior to superovulation therapy. Although the fertilisation rate per oocyte (51%) was significantly lower in Group 3 (P < 0.001), the percentage of cycles in which fertilisation occurred (86%, 78%, 78%) and the pregnancy rates per embryo transfer (17.7%, 17.2%, 18.6%) for Groups 1, 2 and 3, respectively, were not significantly different. Pretreatment with GnRH analogues allows patients with endometriosis to achieve similar success rates to patients with tubal infertility alone.

Endometriosis: medical therapy

The management of women with endometriosis is complex and necessitates individualization of patient care. The most commonly used medical therapies are danazol, GnRH agonists, medroxyprogesterone acetate and gestrinone. Studies to date have shown these drugs to have equal efficacy in terms of reduction in laparoscopic score and relief of symptoms. However, their side-effects make them unsuitable for long-term use. The addition of low dose hormone replacement therapy to GnRH agonist regimens may allow prolonged use but the current cost of these agents is high. Low dose oral contraceptive pills deserve further investigation. The role of medical treatment for women with endometriosis and infertility is controversial. There is no place for hormonal therapy in such women with stage I or II disease. When expectant management fails, gamete intrafallopian transfer offers excellent results. For those with stage III or IV disease, surgery is preferable with adjunctive medical therapy in selected cases. If pregnancy does not ensue, in vitro fertilization and embryo transfer are the next line of management, and results are optimized by prior medical therapy and aspiration of endometriomas. Major advances have been made in the medical management of endometriosis. However, current treatment strategies are ineffective in eliminating the disease in most women. New approaches are required in both basic and clinical research in order to finally eradicate this often devastating disease.

Cycle characteristics and outcome in relation to ovarian response during in vitro fertilization

PURPOSE

This retrospective analysis of 148 non-male factor couples sought to determine whether oocyte or embryonic quality was compromised by the magnitude of the ovarian response following clomiphene citrate/human menopausal gonadotropin stimulation for in vitro fertilization.

METHODS

Increased oocyte numbers were associated with decreased fertilization rates (r = -0.36, P < 0.001) and estradiol/follicle ratios (r = -0.443, P < 0.001), although the quality of the resulting embryos was not affected. Despite reduced fertilization, higher oocyte numbers yielded additional healthy embryos (r = 0.70, P < 0.001) for immediate replacement or cryopreservation. Implantation rates did not differ among groups and no predictive variables were identified.

RESULTS

These results suggest that endometrial receptivity and implantation were not adversely affected by increasing estradiol levels. The decline in oocyte quality associated with the retrieval of larger numbers of oocytes appeared to be offset by the availability of additional embryos for immediate replacement and cryopreservation.

Laparoscopic ablation of endometriosis using the cavitational ultrasonic surgical aspirator

Surgical modalities such as electrosurgery and lasers have been used for many years to treat endometriosis. They are relatively unselective with wide scatter, however, leading to the potential for significant tissue damage and injury. As an alternative, a technique for performing laparoscopic excision and adhesiolysis using a cavitational ultrasonic surgical aspirator (CUSA) was developed and studied in 15 patients. Endometriosis was removed using a prototype titanium probe developed for a 10-mm laparoscopic port. The ultrasonic laparoscopic probe consisted of an acoustic vibrator, a coupling device, a removable tip, and a protective flue. Vibrations from the acoustic vibrator (magnetostrictive device) were conveyed to the operating tip through a coupling piece. The magnetostrictive device consisted of nickel alloy laminations 10.8 cm in length that transformed electrical energy into mechanical motion at the hollow titanium tip, vibrating at a frequency of 23 kHz. The excursion of the tip (amplitude setting) was arbitrarily set, with a fixed stroke of 200 microm in all cases to remove tissue with a 1- to 2-mm radius of the vibrating tip. The tip was tapered to obtain greater amplitude and ablation efficiency. When placed in contact with the endometriotic implants and adhesions, it destroyed and emulsified the cell membranes, which were irrigated and removed through a built-in suction tube. The resulting debris and irrigating fluid were removed through the hollow central portion of the probe. The vibrating tip was moved over the surgical site in a back-and-forth motion to allow continuous, controlled removal. Vessels larger than 0.5 mm in diameter, nerves, and fibrous tissue capsules rebounded with the ultrasonic vibration waves emitted by the CUSA, and thus were unimpaired by the procedure. The consistency of tissues was sensed accurately when the tip of the device was in contact with them. This tactile feedback was helpful in enabling the surgeon to differentiate target tissues. The future application of this instrument awaits the outcome of research.

The impact of endometriosis on the reproductive outcome of infertile patients

OBJECTIVE

We examined whether the presence and severity of endometriosis affect the reproductive outcome of infertile patients.

STUDY DESIGN

The conception rates of 2080 infertile women, 1263 who had endometriosis and 817 who did not have endometriosis, were analyzed retrospectively by means of the chi 2 test. Depending on the stage of the disease patients who had endometriosis-associated infertility underwent expectant management, danazol therapy, or minor or major conservative surgery. The patients who failed to conceive after these conventional treatments were enrolled in the in vitro fertilization-embryo transfer program.

RESULTS

The conception rates were virtually identical regardless of the presence or absence of endometriosis (30.7% vs 30.0%). The outcome of in vitro fertilization-embryo transfer was not affected either by the presence or the severity of the disease.

CONCLUSION

Endometriosis had no impact on the reproductive outcome of infertile patients in this series unless the anatomy of the pelvic organs was heavily distorted, which can occur in the advanced stages of the disease.

Abbreviated endometriosis-associated infertility correlates with in vitro fertilization success

The utility of in vitro fertilization (IVF) for refractory infertility associated with endometriosis was studied by reviewing the 6-year experience with IVF and pregnancy follow-up at University Hospital, London, Ontario. Two hundred forty cycles were begun in 124 couples in whom endometriosis was the sole identified cause of infertility. In a program employing predominantly ultrasound-guided transvaginal oocyte retrieval, live birth rates were not reduced with advanced degrees of endometriosis. Live births were positively correlated with a shorter infertility duration.

Structural and ultrastructural defects in preovulatory endometrium of normo-ovulating infertile women with minimal or mild endometriosis

To investigate whether a primary endometrial factor is involved in the pathogenesis of infertility in patients with minimal or mild endometriosis, we compared light, scanning, and transmission electron microscopic studies of preovulatory endometria of 15 endometriotic patients with 12 normal controls. All the women were infertile and normo-ovulating by standard criteria. Six morphometric indexes were considered. The scanning electron microscopic analysis revealed heterogeneity of the endometrial surface epithelium in 77% of the patients with endometriosis and in 16% of the controls. Glandular and stromal mitoses, basal vacuolated cells, and the ciliated:nonciliated cell ratio was significantly reduced in the endometriosis group compared with the controls. Further studies are needed to clarify the role of the observed endometrial anomalies in the pathogenesis of infertility associated with endometriosis.

Endometriosis-associated infertility treated by long-term gonadotropin-releasing hormone agonist administration and assisted fertilization

Two patients with long-lasting infertility associated with moderate and severe symptomatic endometriosis were treated with long-term GnRH-agonist suppression of ovarian function. Both patients were relieved of their endometriosis-related abdominal pains during the first treatment month. After an additional treatment period of 3 to 5 months, assisted fertilization was performed, resulting in an ongoing pregnancy for both patients.

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.

The effect of endometriomas on in vitro fertilization outcome

To determine the effect of ovarian endometriomas on in vitro fertilization (IVF) outcome, two groups of patients were studied. Group I consisted of seven patients with ovarian endometriomas and severe pelvic adhesions treated for a total of 12 cycles. Group II patients consisted of eight patients with hydrosalpinges and comparable pelvic adhesions treated for a total of 27 cycles. There were no differences in the number of days required for stimulation or in the serum estradiol levels attained between the two groups. Group I patients were noted to have significantly fewer preovulatory follicles (1.42 vs 3.33, P less than 0.005), cycles with fertilization (28 vs 84%, P less than 0.005), and embryos transferred (0.78 vs 2.56, P = 0.01) than Group II patients. Three pregnancies occurred in Group II, while there were no conceptions among Group I patients. This study suggests that the presence of an ovarian endometrioma(s) has an adverse effect on IVF outcome and suggests that patients with ovarian endometriomas should have them removed prior to undergoing IVF.