Diagnostics · Ultrasound
Abstract
Endometriosis fertility index (EFI) is a robust tool to predict the pregnancy rate in patients with endometriosis who are attempting non-in vitro fertilization conception. However, EFI calculation requires laparoscopy. Newly established imaging techniques such as sliding sign, which is used to diagnose pouch of Douglas obliteration, could provide a promising alternative. The objective of this study was to investigate the practicality of using ultrasound data to predict a low EFI (score ≤6).
Observational study from a prospective registry (Endometriosis Pelvic Pain Interdisciplinary Cohort, clinicaltrials.gov #NCT02911090). Analyzed data were captured from December 2013 to June 2017.
Tertiary referral center at British Columbia Women's Hospital.
We analyzed data for 2583 participants from the Endometriosis Pelvic Pain Interdisciplinary Cohort. In this cross-sectional study, we included 86 women aged <40 years.
Dynamic ultrasonography for the sliding sign testing and EFI calculation during laparoscopic surgery.
Logistic regression was used to obtain receiver operating characteristic area under the curve (AUC) for the prediction models. Significance was p <.05. Patients with a negative sliding sign were older and had severe endometriosis and longer duration of infertility. Patients with a negative sliding sign had significantly lower total EFI scores and lower surgical factors scores than patients with a positive sliding sign. Logistic regression showed that a negative sliding sign and EFI historic factors score can predict an EFI score ≤6 (sensitivity = 87.9%, specificity = 81.1%, AUC = 0.93 [95% confidence interval, 0.88-0.98]). Adding the diagnosis of endometrioma to the previous prediction model resulted in AUC = 0.95 (95% confidence interval, 0.90-0.995), sensitivity = 84.8%, and specificity = 92.5%.
The sliding sign could be a potential alternative to the EFI surgical factors, and it could be used in combination with EFI historic factors and the diagnosis of endometrioma to predict an EFI score ≤6 for patients who are not scheduled for immediate surgery.
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By this author
Mid-Cycle Pain in Endometriosis: Clinical Correlations and Potential Etiological Factors
Rojas HE et al., 2026 · Journal of women's health (2002)
To characterize differences between individuals with and without mid-cycle pain in a registry cohort with endometriosis. Prospective analysis of data from the Endometriosis Pelvic Pain Interdisciplinary Cohort Data Registry (Clinicaltrials.gov #NCT02911090) at a tertiary referral center in Western Canada. Three hundred forty-five individuals aged 18-49 years who: (1) had at least one episode of menstrual bleeding in the last 3 months, (2) attended a baseline initial visit, and (3) subsequently had surgery with histological confirmation of endometriosis between January 2018 and December 2023. Exclusion criteria included (1) previous hysterectomy; (2) hormonal suppressive therapy use in the last 3 months; and (3) missing data on mid-cycle pain, history of hormonal therapy use, or menstrual cycle regularity. N/A. Mid-cycle pain in the last month versus No mid-cycle pain in the last month. Of the 345 participants, 67% (n = 232) reported mid-cycle pain in the last month. Mid-cycle pain in the last month was significantly associated with higher mean Central Sensitization Inventory score (48 ± 17 versus 36 ± 16, p < 0.001) and more months of prior hormonal suppressive therapy use (58 [14-120] versus 26 [0-109], p = 0.012). Abnormal anatomy at the time of surgery (e.g., endometrioma, ovarian adhesions) was not associated with mid-cycle pain in the last month. In this endometriosis cohort at a tertiary referral center, most participants reported mid-cycle pain in the last month, which was associated with central sensitization but was not clearly related to endometriosis anatomical distortion.
Impact of the coronavirus disease-2019 (COVID-19) pandemic on reproductive outcomes in patients with recurrent pregnancy loss
Balachandran S et al., 2026 · Journal of obstetrics and gynaecology Canada : JOGC = Journal d'obstetrique et gynecologie du Canada : JOGC
To assess the impact of the COVID-19 pandemic on reproductive outcomes in patients with recurrent pregnancy loss (RPL) and the influence of material and social deprivation on these outcomes. This retrospective cohort study included RPL patients seen at a specialized clinic between March 1, 2018, and February 28, 2022. Patients were categorized into two groups based on care period: pre-pandemic (March 1, 2018-February 29, 2020) and pandemic (March 1, 2020-February 28, 2022). Cumulative probabilities of birth were estimated using the cumulative incidence function within a competing risk framework, treating pregnancy loss as a competing event. Fine and Gray regression models calculated sub-distribution hazard ratio (sHR) of birth. 544 patients were included in the study, with 255 in the pre-pandemic group and 289 in the pandemic group. Individuals in the pandemic group were less likely to achieve pregnancy than those in the pre-pandemic group (relative risk = 0.50, 95% confidence interval [CI] 0.39 - 0.66). Among those who conceived, the cumulative probability of live birth was 0.77 in both groups. Relative to individuals residing in high-social deprivation neighborhoods, those living in moderately deprived areas had higher sub-distribution hazards of live birth (adjusted sHR = 1.97, 95% CI 1.25 - 3.10; P = 0.003). Within specialized RPL care and a universal maternity care system, pregnancy rates were lower during the first two years of the COVID-19 pandemic. However, among those who conceived, the probability of achieving a live birth remained similar between the pre-pandemic and pandemic periods.
Using corpus luteum formation with dominant follicle collapse to improve the criteria for identifying ovulation
Bouchard TP et al., 2026 · Reproductive biomedicine online · Free to read
Does formation of the corpus luteum help to identify the day of ovulation on ultrasound when follicular collapse is missed, and how reliable are sonographers versus a review panel in identifying the day of ovulation on ultrasound? Sonographers in a clinic in Canada performed serial endovaginal ultrasound scans (six to eight per cycle) to identify the day of ovulation in regularly cycling women (n = 40) who were followed for one to five cycles (n = 85). The day of ovulation was identified by: (i) identification of the dominant follicle; (ii) disappearance of the dominant follicle; and (iii) identification and dating of the corpus luteum. The main outcome measures were inter-rater reliability between two sonographers, and Bland-Altman agreement between the supervising sonographer and a panel that reviewed each scan to identify the day of ovulation. Of the 85 menstrual cycles reviewed, two cycles did not have sufficient data to date ovulation, one cycle showed an incidental dermoid cyst, and 11 cycles showed anovulatory patterns. This left a total of 71 cycles (84%) for which intra-rater reliability between two sonographers for identifying the day of ovulation was high (intraclass correlation coefficient = 0.99, P < 0.0001), and Bland-Altman agreement showed no significant difference in the estimated day of ovulation between the supervising sonographer and the panel (t = -0.28, P = 0.78). Corpus luteum criteria were necessary to help identify the day of ovulation in 14 of 71 cycles (20%). The estimated day of ovulation can be determined reliably on ultrasound by trained sonographers using collapse of the dominant follicle and formation of the corpus luteum based on six to eight scans per cycle.
Guideline No. 468: Clinical Management of Endometriosis
Yong PJ et al., 2026 · Journal of obstetrics and gynaecology Canada : JOGC = Journal d'obstetrique et gynecologie du Canada : JOGC
To provide health care professionals with an evidence-based approach to the management of endometriosis and its associated symptoms. Women and gender-diverse individuals affected by endometriosis. BENEFITS, HARMS, Timely and effective management of endometriosis has the potential to reduce pain, improve fertility and quality of life, and enhance long-term health outcomes. Early intervention may also help mitigate the financial and health system burdens associated with delayed diagnosis and treatment. Published literature was retrieved through searches of PubMed, Ovid, Medline, Embase, Scopus, and the Cochrane Library from August 2010 through December 2025, using relevant MeSH heading and keywords. Results were restricted to systematic reviews, meta-analyses, randomized controlled trials/controlled clinical trials, observational studies, and clinical practice guidelines. Results were limited to English or French language materials. Evidence was supplemented with references from the 2010 Society of Obstetricians and Gynaecologists of Canada guideline No. 244. The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and conditional recommendations). Health care providers involved in the care of individuals with endometriosis. Early identification and management of endometriosis can significantly improve patient outcomes, reduce long-term health care costs and improve their quality of life. RECOMMENDATIONS.
Related research
Validation study of nonsurgical diagnosis of endometriosis
Eskenazi B et al., 2001 · Fertil Steril
To determine whether the surgical diagnosis of endometriosis can be predicted using symptoms, signs, and ultrasound findings. Prospective study (study sample); retrospective record review (test sample). Hospital of Desio (study sample) and Mangiagalli Hospital (test sample), Italy. PATIENT(S): Ninety women scheduled to undergo laparoscopy or laparotomy (study sample); 120 women who underwent laparoscopy (test sample). The study sample group was interviewed before surgery about infertility and dysmenorrhea, dyspareunia, and noncyclic pelvic pain and each member had a pelvic examination and a transvaginal ultrasound. At surgery, endometriosis was noted. For the test sample, the same information was abstracted from medical records after laparoscopy. MAIN OUTCOME MEASURE(S): The ability of symptoms, signs, and ultrasound to predict endometriosis at surgery. A classification tree was developed with the study sample and evaluated with the test sample. RESULT(S): Ovarian endometriosis, but not nonovarian endometriosis, could be reliably predicted with noninvasive tools. Ultrasound and examination best predicted ovarian endometriosis, correctly classifying 100% of cases with no false positive diagnoses in the study sample. Similar results were found in the test sample. CONCLUSION(S): Noninvasive tools may be used to identify women with ovarian, but not nonovarian endometriosis, with excellent agreement with surgical diagnosis.
Prediction of Pouch of Douglas Obliteration: Point-of-care Ultrasound Versus Pelvic Examination
Arion K et al., 2019 · Journal of minimally invasive gynecology
To evaluate the point-of-care preoperative transvaginal ultrasound (TVUS) sliding sign in comparison with palpation of a nodule on digital pelvic examination for the prediction of pouch of Douglas (POD) obliteration. Analysis of data from a prospective data registry (Canadian Task Force classification II-2). A tertiary referral center. Women with suspected endometriosis who had preoperative pelvic examination and point-of-care TVUS followed by laparoscopic surgery between August 2015 and December 2016. Women were preoperatively assessed for the prediction of POD obliteration with pelvic examination for a nodule and point-of-care TVUS uterine/cervix sliding sign. The study included 269 women, 15.2% (41/269) of whom had POD obliteration at the time of surgery. A preoperative negative sliding sign had a sensitivity of 73.2% (95% confidence interval, 57.1%-85.8%) and a specificity of 93.9% (95% CI, 89.9%-96.6%) in the prediction of POD obliteration compared with preoperative palpation of a nodule on pelvic examination, which had a sensitivity of 24.4% (95% CI, 12.4%-40.3%) and a specificity of 93.4% (95% CI, 89.4%-96.3%). The difference in sensitivity was statistically significant (McNemar test, p <.001). A negative sliding sign was also associated with longer operating times and more difficult surgery including the need for ureterolysis. The point-of-care TVUS sliding sign showed significantly improved sensitivity compared with palpation of a nodule on pelvic examination for the prediction of POD obliteration. Therefore, the point-of-care TVUS sliding sign improves the preoperative assessment of POD disease and thus may lead to more optimal surgical planning in women with suspected endometriosis.
Endometriosis fertility index: the new, validated endometriosis staging system
Adamson GD et al., 2010 · Fertility and Sterility
To develop a clinical tool that predicts pregnancy rates (PRs) in patients with surgically documented endometriosis who attempt non-IVF conception. Prospective data collection on 579 patients and comprehensive statistical analysis to derive a new staging system--the endometriosis fertility index (EFI)--from data rather than a priori assumptions, followed by testing the EFI prospectively on 222 additional patients for correlation of predicted and actual outcomes. Private reproductive endocrinology practice. PATIENT(S): A total of 801 consecutively diagnosed and treated infertile patients with endometriosis. INTERVENTION(S): Surgical diagnosis and treatment followed by non-IVF fertility management. MAIN OUTCOME MEASURE(S): The EFI and life table PRs. RESULT(S): A statistically significant variable used to create the EFI was the least function score (i.e., the sum of those scores determined intraoperatively after surgical intervention that describe the function of the tube, fimbria, and ovary on both sides). Sensitivity analysis showed that the EFI varies little, even with variation in the assignment of functional scores, and predicted PRs. CONCLUSION(S): The EFI is a simple, robust, and validated clinical tool that predicts PRs after endometriosis surgical staging. Its use provides reassurance to those patients with good prognoses and avoids wasted time and treatment for those with poor prognoses.
Deep Dyspareunia, Superficial Dyspareunia, and Infertility Concerns Among Women With Endometriosis: A Cross-Sectional Study
Wahl KJ et al., 2020 · Sexual medicine · Free full text on PubMed Central
Deep dyspareunia is a cardinal symptom of endometriosis, and as many as 40% of people with this condition experience comorbid superficial dyspareunia. To evaluate the relationship between sexual pain and infertility concerns among women with endometriosis. This is a cross-sectional study conducted at a university-based tertiary center for endometriosis. 300 reproductive-aged participants in the prospective Endometriosis Pelvic Pain Interdisciplinary Cohort (ClinicalTrials.gov Identifier: NCT02911090) with histologically confirmed endometriosis were included (2013-2017). The total score on the infertility concerns module of the Endometriosis Health Profile-30 categorized into 5 groups (0, 1-4, 5-8, 9-12, 13-16). The odds of infertility concerns did not increase with severity of deep dyspareunia (odds ratio = 1.02, 95% CI: 0.95-1.09, P = .58). However, the odds of infertility concerns increased with severity of superficial dyspareunia (odds ratio = 1.09, 95% CI: 1.02-1.16, P = .011); this relationship persisted after adjusting for endometriosis-specific factors, infertility risk factors, reproductive history, and demographic characteristics (adjusted odds ratio [AOR] = 1.14, 95% CI: 1.06-1.24, P < .001). Other factors in the model independently associated with increased infertility concerns were previous difficulty conceiving (AOR = 2.09, 95% CI 1.04-4.19, P = .038), currently trying to conceive (AOR = 5.23, 95% CI 2.77-9.98, P < .001), nulliparity (AOR = 3.21, 95% CI 1.63-6.41, P < .001), and younger age (AOR = 0.94, 95% CI: 0.89-0.98, P = .005). Severity of superficial dyspareunia, but not deep dyspareunia, was associated with increased odds of infertility concerns among women with endometriosis. Strengths of the study included the use of a validated measure of infertility concerns and disaggregation of sexual pain into deep and superficial dyspareunia. Limitations included the setting of a tertiary center for pelvic pain, which affects generalizability to fertility clinic and primary care settings. Women experiencing introital dyspareunia, who can have difficulties with achieving penetrative intercourse, may be concerned about their future fertility and should be counselled appropriately. Wahl KJ, Orr NL, Lisonek M, et al. Deep Dyspareunia, Superficial Dyspareunia, and Infertility Concerns Among Women With Endometriosis: A Cross-Sectional Study. Sex Med 2020;8:274-281.