Endometrial Volume Measurements Research Articles

Automated endometrial identification and volume calculation in normal uteri using a novel smart ERA technique

To evaluate the repeatability of a novel automated technique called Smart ERA (Smart Endometrial Receptivity Analysis) for the automated segmentation and volume calculation of the endometrium in patients with normal uteri,, and to compare the agreement of endometrial volume measurements between Smart ERA, the semi-automated Virtual Organ Computer-aided Analysis (VOCAL) technique and manual segmentation. This retrospective study evaluated endometrial volume measurement in infertile patients who underwent frozen-thawed embryo transfer (FET). Transvaginal three-dimensional ultrasound scans were performed using a Resona R9 ultrasound machine. Data was collected from patients between 2021 and 2022. Patients with normal uteri and optimal ultrasound images were included. Endometrial volumes were measured using Smart ERA, VOCAL at 15° rotation, and manual segmentation. Intra-observer repeatability and agreement between techniques were assessed using the intraclass correlation coefficient (ICC) and Bland–Altman analysis. A total of 407 female patients were evaluated (mean age 33.2 ± 4.7 years). The repeatability of Smart ERA showed an ICC of 0.983 (95% CI 0.984–0.991). The agreement between Smart ERA and the manual method, Smart ERA and VOCAL, and VOCAL and the manual method, as assessed by ICC, were 0.986 (95% CI 0.977–0.990), 0.943 (95% CI 0.934–0.963), and 0.951 (95% CI 0.918–0.969), respectively. The Smart ERA technique required approximately 3 s for endometrial volume calculation, while VOCAL took around 5 min and the manual segmentation method took approximately 50 min. The Smart-ERA software, which employs a novel three-dimensional segmentation algorithm, demonstrated excellent intra-observer repeatability and high agreement with both VOCAL and manual segmentation for endometrial volume measurement in women with normal uteri. However, these findings should be interpreted with caution, as the algorithm's performance may not be generalizable to populations with different uterine characteristic. Additionally, Smart ERA required significantly less time compared to VOCAL and manual segmentation.

The diagnostic function of office hysteroscopy and three-dimensional (3D) endometrial volume measurement in the evaluation of women with perimenopausal bleeding

The diagnostic function of office hysteroscopy and three-dimensional (3D) endometrial volume measurement in the evaluation of women with perimenopausal bleeding

Relationship between Transvaginal Ultrasound Endometrial Volume, Body Mass Index and Endometrial Pathology in Women with Postmenopausal Bleeding

Abstract Background Menopause is recognized to have occurred after one year of amenorrhea, for which there is no other obvious pathological or physiological cause. Perimenopause should include the period immediately prior to the menopause (when the endocrinological, biological and clinical features of approaching menopause commence) and the first one year after menopause. Objectives The aim of the study is classification of patients into those with benign endometrial pathology and those with endometrial hyperplasia or carcinoma using endometrial volume and BMI. Patients and Methods This observational cross sectional study was conducted at the Department of Obstetrics and Gynecology in Ain Shams University Hospital from March 2019 till January 2020. The population of this study was 100 menopausal women with postmenopausal bleeding ≥12 months and endometrial thickness by TVUS ≥5 mm. Results According to histopathology of endometrial carcinoma, statistical analysis of our data revealed that age, menopausal duration and BMI were significantly highest. Parity was significantly lowest. Endometrial volume was significantly highest in carcinoma (7.9±2.9 cc). Age, menopausal duration, parity and endometrial volume had significant moderate diagnostic performance in predicting endometrial carcinoma but BMI had significantly low. Age ≥ 62.0, menopausal duration ≥ 11.0 and parity ≤3.0 had low diagnostic characteristics in diagnosis of endometrial carcinoma but endometrial volume ≥ 6.0 had high sensitivity but low other diagnostic characteristics in the diagnosis of endometrial carcinoma. According to histopathology of endometrial hyperplasia, statistical analysis of our data revealed that age, menopausal duration, BMI, parity and endometrial volume had no significant diagnostic performance in the diagnosis of endometrial hyperplasia. Conclusion In our study, analysis of data revealed that the using of transvaginal measurement of endometrial volume is the best predictor of endometrial cancer with a positive correlation with BMI.

The measurement of endometrial volume and sub-endometrial vascularity to replace the traditional endometrial thickness as predictors of in-vitro fertilization success

To assess the value of endometrial thickness, volume, and sub-endometrial perfusion in women undergoing IVF. In 82 women candidate for ICSI, endometrial thickness and sub-endometrial perfusion were measured with a trans-vaginal 2 D ultrasound and 3 D power Doppler respectively on day of hCG trigger and Embryo transfer (ET). The primary outcome was the clinical pregnancy rate. Endometrial volume showing a statistically significant difference between pregnant and nonpregnant women (4.11 ± 1.19 vs. 3.4 ± 1.1 p = .019) on day of triggering and at ET (4.02 ± 1.15 vs. 3.45 ± 0.90, p = .022). VFI was significantly higher in pregnant group at both days of triggering and ET (0.54 ± 0.48 vs. 0.33 ± 0.31 and 0.47 ± 0.22 vs. 0.34 ± 0.2, p = .02). At cutoff values of 3.265 and 2.95 cm3 (70 & 80% sensitivity, specificity 64.5 & 51.6%, a positive predictive value 38.9 & 34.8%, and negative predictive value 87.0 & 88.9%) to predict pregnancy on the day of hCG trigger & ET respectively. Cutoff value for Endometrial VFI on the day of ET was 0.674 (sensitivity of 70%, specificity of 80.6%, PPV 53.8%, and NPV 89.3%). Higher endometrial volume and VFI were associated with pregnancy.

Low serum progesterone on the day of embryo transfer is associated with a diminished ongoing pregnancy rate in oocyte donation cycles after artificial endometrial preparation: a prospective study.

Is there a relationship between serum progesterone (P) and endometrial volume on the day of embryo transfer (ET) with ongoing pregnancy rate (OPR) in artificial endometrium preparation cycles? Patients with serum P < 9.2 ng/ml on the day of ET had a significantly lower OPR but endometrial volume was not related with OPR. A window of optimal serum P levels during the embryo implantation period has been described in artificial endometrium preparation cycles. A very low endometrial volume is related to poor reproductive outcome. Prospective cohort study with 244 patients who underwent ET in an oocyte donation cycle after an artificial endometrial preparation cycle with estradiol valerate and vaginal micronized progesterone (400 mg/12 h). The study period went from 22 February 2016 to 25 October 2016 (8 months). Sample size was calculated to detect a 20% difference in OPR (35-55%) between two groups according to serum P levels in a two-sided test (80% statistical power, 95% confidence interval (CI)). Patients undergoing their first/second oocyte donation cycle, aged <50, BMI < 30 kg/m2, triple layer endometrium >6.5 mm and 1-2 good quality transferred blastocysts. A private infertility centre. Serum P determination and 3D ultrasound of uterine cavity were performed on the day of ET. Endometrial volume measurements were taken using a virtual organ computer-aided analysis (VOCAL™) system. The primary endpoint was OPR beyond pregnancy week 12. About 211 of the 244 recruited patients fulfilled all the inclusion/exclusion criteria. Mean serum P on the day of embryo transfer was 12.7 ± 5.4 ng/ml (Centiles 25, 9.2; 50, 11.8; 75,15.8). OPRs according to serum P quartiles were: Q1: 32.7%; Q2: 49.1%; Q3: 58.5%; Q4: 50.9%. The OPR of Q1 was significantly lower than Q2-Q4: 32.7% versus 52.8%; P = 0.016; RR (95% CI): 0.62 (0.41-0.94). The mean endometrial volume was 3.4 ± 1.9 ml. Serum P on the day of ET did not correlate with endometrial volume. A logistic regression analysis, adjusted for all the potential confounders, showed that OPR significantly lowered between women with serum P < 9.2 ng/ml versus ≥9.2 ng/ml (OR: 0.297; 95%CI: 0.113-0.779); P = 0.013. The ROC curve showed a significant predictive value of serum P levels on the day of ET for OPR, with an AUC (95%CI) = 0.59 (0.51-0.67). Only the women with normal uterine cavity, appropriate endometrial thickness and good quality blastocysts transfer were included. Extrapolation to an unselected population or to other routes and/or doses of administering P needs to be validated. The role of endometrial volume could not be fully defined as very few patients presented a very low volume. The present study suggests a minimum threshold of serum P values on the day of ET that needs to be reached in artificial endometrial preparation cycles to optimize outcome. No upper threshold could be defined. None. NCT02696694.

3D-Endometrial volume and outcome of cryopreserved embryo replacement cycles

The success of artificial reproductive techniques not only depends on the quality of oocytes and spermatozoa but also on the receptivity of the endometrium. The aim of this study was to assess the value of measurement of endometrial volume by three-dimensional (3D) in comparison to 2D-ultrasound in the prediction of implantation in women having transfer of cryopreserved embryos. One hundred and eight couples were included in this prospective study. All patients underwent the IVF or ICSI program and had transfer of cryopreserved embryos. Sixty-eight transfers were done in a spontaneous cycle and 40 in an artificial cycle. Endometrial thickness, pattern and three-dimensional volume were measured immediately before embryo transfer. Twenty clinical pregnancies were achieved (PR 18.5 % per transfer), the PR being similar in spontaneous (22.1 %) and artificial (12.5 %, ns) cycles. Three to five days after ovulation (spontaneous cycles) or after the endometrium reached a thickness of at least 8 mm (artificial cycles), a median of three embryos were replaced. In spontaneous cycles, there were no significant differences in endometrial thickness or volume between pregnant (11.9 mm, 2.9 ml) and non-pregnant women (10.7 mm, 3.4 ml). In artificial cycles, the endometrial volume (3.9 vs. 2.5 ml, p < 0.05), but not endometrial thickness (10.7 vs. 10.2 mm, ns) was significantly higher in pregnant than in non-pregnant women. In artificial cycles, a low endometrial volume is associated with a poor likelihood of implantation. Endometrial volume measured by 3D-ultrasound is an objective parameter to predict endometrial receptivity.

A standardized measurement technique may improve the reliability of measurements of endometrial thickness and volume

To investigate whether standardization of the multiplanar view (SMV) when evaluating the uterus using three-dimensional ultrasonography (3D-US) improves intra- and interobserver reliability and agreement with regard to endometrial measurement. Two-dimensional (2D) and 3D-US was used to measure endometrial thickness by two observers in 30 women undergoing assisted reproduction treatment. Endometrial volume was measured with Virtual Organ Computer-aided AnaLysis (VOCAL(™)) in the longitudinal (A) and coronal (C) planes using an unmodified multiplanar view (UMV) and a standardized multiplanar view (SMV). Measurement reliability was evaluated by intraclass correlation coefficient (ICC) and agreement was examined using Bland-Altman plots with limits of agreement (LoA). The ease of outlining the endometrial-myometrial interface was compared between the A- and C-planes using subjective assessment. Endometrial volume measurements using the SMV and A-plane were more reliable (intra- and interobserver ICCs, 0.979 and 0.975, respectively) than were measurements of endometrial thickness using 2D-US (intra- and interobserver ICCs, 0.742 and 0.702, respectively) or 3D-US (intra- and interobserver ICCs, 0.890 and 0.784, respectively). The LoAs were narrower for SMV than for UMV. Reliability and agreement were not much different between the A- and C-planes. However the observers agreed that delineating the endometrial-myometrial interface using the A-plane was easier (first and second observer, 50.0 and 46.7%, respectively) or 'comparable' (50 and 53.3%, respectively), but never more difficult than using the C-plane. Endometrial volume measurements are more reliable than endometrial thickness measurements and are best performed using SMV and the A-plane.

OC05.05: Endometrial volume measurements by transvaginal 3‐dimensional ultrasound for the prediction of outcome in the pregnancies of unknown location

OC05.05: Endometrial volume measurements by transvaginal 3‐dimensional ultrasound for the prediction of outcome in the pregnancies of unknown location

OC09.02: Endometrial volume measurements by transvaginal three-dimensional ultrasound for the prediction of outcome in the pregnancies of unknown location

OC09.02: Endometrial volume measurements by transvaginal three-dimensional ultrasound for the prediction of outcome in the pregnancies of unknown location

OP30.05: The diagnostic value of endometrial volume and vascularity measurement by transvaginal three-dimensional ultrasonography and power Doppler angiography in patients with postmenopausal bleeding

OP30.05: The diagnostic value of endometrial volume and vascularity measurement by transvaginal three-dimensional ultrasonography and power Doppler angiography in patients with postmenopausal bleeding

Will Endometrial Volume Measurements Add Something New to the Diagnosis of Early Pregnancy?

Transvaginal ultrasound will detect an intrauterine pregnancy, first seen as a visible gestational sac, as early as four weeks and 3-4 days (day 31-32 of the cycle) after the last menstrual period. However, our knowledge of ultrasonically detectable endometrial changes before the gestational sac visualization is minimal. With the recent introduction of a three-dimensional (3D) ultrasound with the Virtual Organ Computer-aided Analysis (VOCAL) software, it has become possible to measure endometrial volume, which, because of the shape of the endometrial cavity, was not feasible before. Theoretically, endometrial volume in conception cycles may vary according to patients parity, and status of pregnancy, whether it is normal or abnormal; but it should be increased in pregnant compared to non-pregnant patients. Several studies have been published, investigating the endometrial thickness and volume in the luteal phase of the conception cycle, and finding that the above-mentioned is true. Endometrium does seem to be thicker in conception compared to non-conception cycles, and in normal pregnancy compared to abnormal pregnancy. However, at present there is no enough data to confirm that endometrial volume measurement will be powerful tool in differential diagnosis of early normal and abnormal pregnancy.

OC234: Three‐dimensional endometrial volume and three‐dimensional power Doppler analysis in predicting endometrial carcinoma

Objectives: To evaluate the accuracy of endometrial volume measurement and three-dimensional power Doppler analysis (3DPDA) in the diagnosis of endometrial carcinoma and endometrial hyperplasia in women with postand perimenopausal bleeding. Methods: Some 56 women with postmenopausal and 89 with perimenopausal bleeding were enrolled. All were scheduled for hysteroscopy, dilatation and curettage, endometrial sampling or hysterectomy, and the ultrasound scan was performed within 24 h before the procedure. Endometrial thickness, endometrial volume, vascularity index (VI), flow index (FI) and vascularity–flow index (VFI) were measured. These parameters were compared between the group of women with normal histology (including endometrial polyps) and the pathological group (carcinoma and hyperplasia with or without atypia). Results: Ninety women (62%) had normal histology, 26 (17.9%) had an endometrial polyp, 18 (12.5%) hyperplasia and 11(7.6%) had endometrial carcinoma. Mean endometrial thickness was 11 mm and 15.5 mm in the normal and pathological groups respectively (P < 0.005). The mean endometrial volume was 6.87 mL and 15.5 mL in the two groups respectively (P < 0.001). The VI was 2.27% and 2.95% in the two groups respectively (P = 0.022). The FI was 18.6 and 23.6 in the two groups respectively (P = 0.014). The VFI was 0.68 and 0.89 in the two groups respectively (P = 0.018). The area under the ROC curve was 0.698, 0.728, 0.621, 0.631, and 0.625 for endometrial thickness, endometrial volume, VI, FI and VFI respectively. The best predictor of endometrial carcinoma was an endometrial volume of 3.56 mL or more (sensitivity 93.1%, specificity 36.2%). Conclusions: Endometrial volume and 3D-PDA are good diagnostic tools in predicting endometrial carcinoma and hyperplasia in women with postand perimenopausal bleeding.

OC235: Prenatal diagnosis of skeletal dysplasias in a single institution

Objectives: To evaluate the accuracy of endometrial volume measurement and three-dimensional power Doppler analysis (3DPDA) in the diagnosis of endometrial carcinoma and endometrial hyperplasia in women with postand perimenopausal bleeding. Methods: Some 56 women with postmenopausal and 89 with perimenopausal bleeding were enrolled. All were scheduled for hysteroscopy, dilatation and curettage, endometrial sampling or hysterectomy, and the ultrasound scan was performed within 24 h before the procedure. Endometrial thickness, endometrial volume, vascularity index (VI), flow index (FI) and vascularity–flow index (VFI) were measured. These parameters were compared between the group of women with normal histology (including endometrial polyps) and the pathological group (carcinoma and hyperplasia with or without atypia). Results: Ninety women (62%) had normal histology, 26 (17.9%) had an endometrial polyp, 18 (12.5%) hyperplasia and 11(7.6%) had endometrial carcinoma. Mean endometrial thickness was 11 mm and 15.5 mm in the normal and pathological groups respectively (P < 0.005). The mean endometrial volume was 6.87 mL and 15.5 mL in the two groups respectively (P < 0.001). The VI was 2.27% and 2.95% in the two groups respectively (P = 0.022). The FI was 18.6 and 23.6 in the two groups respectively (P = 0.014). The VFI was 0.68 and 0.89 in the two groups respectively (P = 0.018). The area under the ROC curve was 0.698, 0.728, 0.621, 0.631, and 0.625 for endometrial thickness, endometrial volume, VI, FI and VFI respectively. The best predictor of endometrial carcinoma was an endometrial volume of 3.56 mL or more (sensitivity 93.1%, specificity 36.2%). Conclusions: Endometrial volume and 3D-PDA are good diagnostic tools in predicting endometrial carcinoma and hyperplasia in women with postand perimenopausal bleeding.

Measurement of endometrial volume increase during the first week after embryo transfer by three-dimensional ultrasound to detect pregnancy: a preliminary study

Endometrial volume and thickness were measured in 20 women undergoing in vitro fertilization on the day before the embryo transfer and one week later by three-dimensional ultrasound. The endometrial volume increase was higher in the 8 pregnant women (0.70 cm(3) at least) than in the 12 nonpregnant women (0.21 cm(3) at most).

Three-dimensional endometrial volume and 3-dimensional power Doppler analysis in predicting endometrial carcinoma and hyperplasia

Objective. To evaluate the accuracy of endometrial volume measurement and 3-dimensional power Doppler analysis (3D-PDA) in the diagnosis of endometrial carcinoma and endometrial hyperplasia in women with post- and peri-menopausal bleeding. Methods. 56 women with post-menopausal and 89 with peri-menopausal bleeding were enrolled. All were scheduled for hysteroscopy, dilatation and curettage, endometrial sampling or hysterectomy, and the ultrasound was performed within 24 h before the procedure. Endometrial thickness, endometrial volume, vascularity index (VI), flow index (FI) and vascularity flow index (VFI) were measured. These parameters were compared between the group of women with normal histology (including endometrial polyps) and the pathologic group (carcinoma and hyperplasia with or without atypia). Results. Ninety women (62%) had normal histology, 26 (17.9%) had an endometrial polyp, 18 (12.5%) hyperplasia and 11 (7.6%) had endometrial carcinoma. Mean endometrial thickness was 11 mm and 15.5 mm in the normal and pathologic groups respectively ( p < 0.005). The mean endometrial volume was 6.87 cc and 15.5 cc in the two groups respectively ( p < 0.001). The VI was 2.27% and 2.95% in the two groups respectively ( p = 0.022). The FI was 18.6 and 23.6 in the two groups respectively ( p = 0.014). The VFI was 0.68 and 0.89 in the two groups respectively ( p = 0.018). Using ROC the area under the curve was 0.698, 0.728, 0.621, 0.631, and 0.625 for endometrial thickness, endometrial volume, VI, FI and VFI respectively. The best predictor of endometrial carcinoma was an endometrial volume of 3.56 cc or more (sensitivity 93.1%, specificity 36.2%). Conclusions. Endometrial volume and 3D-PDA are good diagnostic tools in predicting endometrial carcinoma and hyperplasia in women with post- and peri-menopausal bleeding.

Low endometrial volume may predict early pregnancy loss in women undergoing in vitro fertilization

To evaluate the role of 3-D US measurement of the endometrium during early IVF-pregnancy and before the appearance of gestational sac in the prediction of pregnancies outcome. 60 pregnant women following IVF treatment were included in the study. The women underwent transvaginal 3D US measurements of endometrial volume and thickness on day 15-17 post ET. Patients were followed and classified according to pregnancy outcome into 2 further groups. The group with early pregnancy loss and the group with ongoing pregnancy. While no differences were observed between those who miscarried and those who did not in gestational age, endometrial thickness or volume, spontaneous early pregnancy loss was significantly higher in patients with endometrial volume <2 mL as compared to those with endometrial volume >2 mL. 3-D US measurement of endometrial volume of less than 2 mL during early IVF pregnancy and prior to the appearance of gestational sac is a powerful predictor of pregnancy loss.

A reprodutibilidade da medida do volume endometrial por meio do VOCAL: a importância do passo de rotação

OBJETIVOS: avaliar a reprodutibilidade intra-observador e interobservador da medida do volume endometrial utilizando ultra-sonografia tridimensional (3D) e o programa VOCAL® (Virtual Organ Computer-aided AnaLysis). METODOS: um bloco ultra-sonografico 3D do endometrio foi obtido de cinco pacientes inferteis voluntarias que apresentavam diferentes volumes endometriais. Para cada bloco 3D, o volume endometrial foi calculado utilizando o modo manual em quatro diferentes passos de rotacao (30o, 15o, 9o e 6o) por dois diferentes observadores. Dez medidas foram obtidas para cada rotacao e por cada observador. Testamos a diferenca entre as medias com o one-way ANOVA e o pos-teste de Tukey e a reprodutibilidade com os coeficientes de correlacao intraclasse. RESULTADOS: as medidas realizadas com passo de rotacao de 30o foram associadas a medias significativamente menores em 3 das 5 pacientes. Nao houve diferenca entre as medias obtidas pelos passos de rotacao de 15o, 9o ou 6o. Em nenhuma das avaliacoes foi notada diferenca entre as medias obtidas pelos dois observadores. Os coeficientes de correlacao intraclasse foram significativamente menores com o passo de rotacao de 30o (todos abaixo de 0,984) que com os outros passos de rotacao (todos acima de 0,996). CONCLUSOES: o uso de passos de rotacao de 15o ou menos apresentou medidas reprodutiveis do volume endometrial: nao houve diferenca significativa entre as medias obtidas pelos dois observadores, associado ao alto coeficiente de correlacao intraclasse (>0,996). E recomendavel o uso do passo de rotacao de 15o, pois demora menos para ser obtido em comparacao com 6o e 9o.

Endometrial volume and vascularity measurements by transvaginal three-dimensional ultrasonography and power Doppler angiography in stimulated and tumoral endometria: Intraobserver reproducibility

Objectives. To assess intraobserver reproducibility of the endometrial volume (EV) and 3D power Doppler indices (vascularization index, VI; flow index, FI; and vascularization flow index, VFI) of the endometrium and subendometrial area using three-dimensional power Doppler angiography (3D-PDA). Methods. Twenty-five women on the hCG day after controlled ovarian stimulation and 15 patients presenting with uterine bleeding and suspicious endometrial thickening (10 endometrial cancers and 5 endometrial hyperplasias) were scanned. Eighty volume data sets were analyzed using the VOCAL imaging program. EV and VI, FI and VFI of the endometrium and subendometrium (5 mm shell) were manually calculated in the longitudinal and coronal planes with 15° and 9° rotation steps. Intraclass correlation coefficient (ICC) and 95% confidence intervals were used to assess reliability. Results. EV measurements were highly reproducible (ICC ≥ 0.97) without significant differences between planes and rotation steps. Endometrial and subendometrial VI, FI, and VFI presented ICCs above 0.90 with the exception of the subendometrial FI (ICC ≥ 0.80). There were no significant differences according to measurement plane and rotation step except for subendometrial VFI. Nevertheless, 3D power Doppler indices calculated in the coronal plane and 9° rotation step obtained the highest ICC. ICCs for 3D-PDA indices from the tumoral endometria were significantly higher than those calculated from the stimulated endometria. Conclusions. Endometrial volume and endometrial and subendometrial 3D power Doppler indices have an acceptable reproducibility, significantly higher in tumoral endometria. The reliability of measurements does not seem to be significantly influenced by the rotation plane and degrees of rotation. These results support that 3D-PDA and VOCAL are reliable methods to evaluate the physiological and pathological changes of the endometrium.

OC38.02: Screening for Down syndrome with a two‐step approach using first‐trimester combined screening followed by second‐trimester ultrasound examination: an interventional study

Objective: To identify ultrasound measurements which are the best predictors of the presence of retained products of conception (RPOC) within the uterine cavity in women with clinical suspicion of incomplete miscarriage. Methods: This was a prospective study of 200 women with a diagnosis of incomplete miscarriage who were referred for surgical evacuation. All women had a positive urine pregnancy test, and ultrasound findings suggestive of RPOC. The indication for intervention was heavy vaginal bleeding or continuous symptoms following ≥7 days of expectant management. The endometrial thickness and the volume of RPOC (D1 × D2 × D3 × 0.532) were measured preoperatively. The final diagnosis of incomplete miscarriage was based on histopathologic evidence of chorionic villi in the surgical specimen. Results: 189 (94.5%) women had evidence of chorionic villi on histology whilst decidua was only found in the remaining 11 (5.5%) women. On multiple logistic regression analysis the best discriminator between RPOC and decidua was endometrial volume, whilst the endometrial thickness was not statistically significant. Using a cut off level ≥1 ml the odds of tissue representing chorionic villi were 137 (95% CI 24 to 778). Conclusion: The measurement of endometrial volume on ultrasound scan is a better test to diagnose incomplete miscarriage than endometrial thickness.

OC37.02: Ultrasound and histological findings in women with suspected incomplete miscarriage

Objective: To identify ultrasound measurements which are the best predictors of the presence of retained products of conception (RPOC) within the uterine cavity in women with clinical suspicion of incomplete miscarriage. Methods: This was a prospective study of 200 women with a diagnosis of incomplete miscarriage who were referred for surgical evacuation. All women had a positive urine pregnancy test, and ultrasound findings suggestive of RPOC. The indication for intervention was heavy vaginal bleeding or continuous symptoms following ≥7 days of expectant management. The endometrial thickness and the volume of RPOC (D1 × D2 × D3 × 0.532) were measured preoperatively. The final diagnosis of incomplete miscarriage was based on histopathologic evidence of chorionic villi in the surgical specimen. Results: 189 (94.5%) women had evidence of chorionic villi on histology whilst decidua was only found in the remaining 11 (5.5%) women. On multiple logistic regression analysis the best discriminator between RPOC and decidua was endometrial volume, whilst the endometrial thickness was not statistically significant. Using a cut off level ≥1 ml the odds of tissue representing chorionic villi were 137 (95% CI 24 to 778). Conclusion: The measurement of endometrial volume on ultrasound scan is a better test to diagnose incomplete miscarriage than endometrial thickness.