Sonographic Parameters for Prediction of Miscarriage: Role of 3-Dimensional Volume Measurement

Assessing the predictive value of first trimester ultrasound and biochemical markers in miscarriage: A scoping review

INTRODUCTION

Vaginal bleeding in the first trimester of pregnancy generates anxiety and uncertainty for expecting parents. The ability to determine pregnancy outcome through a first trimester ultrasound scan remains a challenge in obstetrics. Several first trimester ultrasound markers used individually or in combination, as well as ultrasound markers used in combination with biochemical markers, have been studied to determine their predictive value in pregnancy outcome. This scoping review was performed to determine which markers have already been investigated for this purpose.

METHODS

An extensive and systematic database search was performed using four different categories of keywords which were combined using Boolean terms. A total of 14 variables were included on the final data charting forms. Data was synthesised collectively for each variable and then separately for the studies analysing only one marker. For the studies which analysed multiple markers, data was synthesised based on the number of markers per study.

RESULTS

The search yielded 3608 studies, of which 128 were ultimately used for this review. Data extraction, based on predetermined eligibility criteria, was performed by two authors independently. Seventy-seven (62.6%) studies investigated the predictive value of a single ultrasound marker. The remaining 46 (37.4%) studies explored multiple markers, of which at least one was an ultrasound marker.

CONCLUSION

This review identified several discrepancies among different studies. This highlights the need for better consensus among researchers to allow for the design of a predictive model which enables extrapolation of findings to all pregnant women.

IMPLICATIONS FOR PRACTICE

Through the study of ultrasound and biochemical markers in the first trimester of pregnancy, clinicians may provide a more accurate prediction of pregnancy outcome following threatened miscarriage.

Incidence of intrauterine adhesion after ultrasound-guided manual vacuum aspiration (USG-MVA) for first-trimester miscarriages: a prospective cohort study

PURPOSE

Ultrasound-guided manual vacuum aspiration (USG-MVA) is a feasible and effective outpatient treatment to treat early pregnancy loss.

METHODS

This was a prospective observational study at a university-affiliated hospital. All women undergoing either a USG-MVA or electric vacuum aspiration (EVA) were invited to return 3-6 months later for follow-up at which women completed a questionnaire to document their post-evacuation menstrual and reproductive history, and underwent a hysteroscopy if they were not pregnant. The severity of intrauterine adhesion (IUA), if present, was graded (Stage I-III) according to the American fertility society classification.

RESULTS

A total of 292 women had a hysteroscopy after their initial surgical evacuation, USG-MVA 169(57.9%) versus EVA 123(42.1%). Women undergoing EVA as opposed to a USG-MVA had a 12.9% higher incidence of IUA (24.1% vs. 37.0%, p = 0.042) equivalent to 1.84 times higher risk (95% CI 1.01-3.34; p = 0.048). Women having EVA continued to show an increased but not statistically significant trend towards an increased risk of IUA after adjusting for the type of miscarriage (aOR = 1.3; 95% CI 0.66-2.50; p = 0.46).

CONCLUSION

There were no significant differences in their reproductive outcomes and fewer women post-USG-MVA complained of hypomenorrhea. IUA may still occur in women undergoing USG-MVA but it is lower than the rate in women undergoing EVA. Clinical trials registry The trial was registered with the Centre for Clinical Research and Biostatistics - Clinical Trials Registry (CCRBCTR), a partner registry of the WHO Primary Registry-Chinese Clinical Trials Registry (ChiCTR) with a Unique Trial Number: CUHK_CCRB00541 on 22 Dec 2016.

Automated prediction of early spontaneous miscarriage based on the analyzing ultrasonographic gestational sac imaging by the convolutional neural network: a case-control and cohort study

Background

It is challenging to predict the outcome of the pregnancy when fetal heart activity is detected in early pregnancy. However, an accurate prediction is of importance for obstetricians as it helps to provide appropriate consultancy and determine the frequency of ultrasound examinations. The purpose of this study was to investigate the role of the convolutional neural network (CNN) in the prediction of spontaneous miscarriage risk through the analysis of early ultrasound gestational sac images.

Methods

A total of 2196 ultrasound images from 1098 women with early singleton pregnancies of gestational age between 6 and 8 weeks were used for training a CNN for the prediction of the miscarriage in the retrospective study. The patients who had positive fetal cardiac activity on their first ultrasound but then experienced a miscarriage were enrolled. The control group was randomly selected in the same database from the fetuses confirmed to be normal during follow-up. Diagnostic performance of the algorithm was validated and tested in two separate test sets of 136 patients with 272 images, respectively. Performance in prediction of the miscarriage was compared between the CNN and the manual measurement of ultrasound characteristics in the prospective study.

Results

The accuracy of the predictive model was 80.32% and 78.1% in the retrospective and prospective study, respectively. The area under the receiver operating characteristic curve (AUC) for classification was 0.857 (95% confidence interval [CI], 0.793–0.922) in the retrospective study and 0.885 (95%CI, 0.846–0.925) in the prospective study, respectively. Correspondingly, the predictive power of the CNN was higher compared with manual ultrasound characteristics, for which the AUCs of the crown-rump length combined with fetal heart rate was 0.687 (95%CI, 0.587–0.775).

Conclusions

The CNN model showed high accuracy for predicting miscarriage through the analysis of early pregnancy ultrasound images and achieved better performance than that of manual measurement.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04936-0.

Prediction of pregnancy loss by early first trimester ultrasound characteristics

BACKGROUND

Pregnancy loss prediction based on routinely measured ultrasound characteristics is generally aimed toward distinguishing nonviability. Physicians also use ultrasound indicators for patient counseling, and in some cases to decide upon the frequency of follow-up sonograms. To improve clinical utility, allocation of cut-points should be based on clinical data for multiple sonographic characteristics, be specific to gestational week, and be determined by methods that optimize prediction.

OBJECTIVES

To identify routinely measured features of the early first trimester ultrasound and the gestational age-specific cut-points that are most predictive of pregnancy loss.

MATERIALS AND METHODS

This was a secondary analysis of 617 pregnant women enrolled in the Effects of Aspirin in Gestation and Reproduction (EAGeR) trial; all women had 1-2 previous pregnancy losses and no documented infertility. Each participant had a single ultrasound with a detectable fetal heartbeat between 6 weeks 0 days and 8 weeks 6 days. Cut-points for low fetal heart rate and small crown-rump length were separately defined for gestational weeks 6, 7, and 8 to optimize prediction. Identity and log-binomial regression models were used to estimate absolute and relative risks, respectively, and 95% confidence intervals between jointly categorized low fetal heart rate, small crown-rump length, and clinical pregnancy loss. Adjusted models accounted for gestational age at ultrasound in weeks. Missing data were addressed using multiple imputation.

RESULTS

A total of 64 women experienced a clinical pregnancy loss following the first ultrasound (10.4%), 7 were lost to follow-up (1.1%), and 546 women (88.5%) had a live birth. Low fetal heart rate and small crown-rump length (≤122, 123, and 158 bpm; ≤6.0, 8.5, and 10.9 mm for gestational weeks 6, 7, and 8, respectively) were independent predictors of clinical pregnancy loss, with greatest risks observed for pregnancies having both characteristics (relative risk, 2.08; 95% confidence interval, 1.24-2.91). The combination of low fetal heart rate and small crown-rump length was linked to a 16% (95% confidence interval, 9.1-23%) adjusted absolute increase in risk of subsequent loss, from 5.0% (95% confidence interval, 1.5-8.5%) to 21% (95% confidence interval, 15-27%). Abnormal yolk sac diameter or the presence of a subchorionic hemmhorage did not improve prediction of clinical pregnancy loss.

CONCLUSION

Identified cut-points can be used by physicians for patient counseling, and in some cases to decide upon the frequency of follow-up sonograms. The specified criteria should not be used to diagnose nonviability.

Effect of adjunctive vaginal progesterone after McDonald cerclage on the rate of second-trimester abortion in singleton pregnancy: a randomized controlled trial

OBJECTIVE

To evaluate the effect of adjunctive use of vaginal progesterone after McDonald cerclage on the rate of second-trimester abortion in singleton pregnancy.

METHODS

A randomized controlled trial at Woman's Health Hospital, Assiut University, Egypt, between April 2017 and March 2019 enrolled women eligible for McDonald cerclage. After cerclage, participants were randomly assigned to receive progesterone (400 mg pessary) once daily until 37 weeks or no progesterone. The primary outcome was rate of abortion before 28 weeks. Secondary outcomes included gestational age at delivery, preterm delivery, mean birthweight, Apgar score, and admission to the neonatal intensive care unit (NICU).

RESULTS

The rate of spontaneous abortion was higher in the no-progesterone group (P=0.016). Mean gestational age and mean birthweight was higher in the progesterone group (P<0.001 and P=0.002, respectively). The frequency of preterm neonates, neonates with Apgar score less than 7, and admission to NICU was higher in the progesterone group than in the no-progesterone group (P=0.005, P=0.008, and P=0.044, respectively).

CONCLUSION

Adjunctive use of vaginal progesterone after McDonald cerclage was found to decrease the frequency of second-trimester abortion and to improve perinatal outcomes in singleton pregnancy. Clinicaltrials.gov: NCT02846909.

First-trimester ultrasound features associated with subsequent miscarriage: A prospective study

BACKGROUND

First-trimester miscarriage is common, with women increasingly offered an ultrasound scan early in the first trimester to assess the status of their pregnancy. Ultrasound is uniquely situated to significantly impact the clinical management of these women.

AIMS

This study aims to determine whether there were any differences in the early ultrasound appearances of pregnancies that continued to be viable or resulted in miscarriage before 12 weeks gestation.

MATERIALS AND METHODS

This was a prospective cohort study including ultrasound measurements: mean sac diameter (MSD), yolk sac diameter (YSD), crown-rump length (CRL), fetal heart rate (FHR), trophoblast thickness, trophoblast volume (TTV) and mean uterine artery pulsatility index (meanUAPI). Regression models were fitted for each parameter and Z-scores compared between cohorts that progressed or miscarried after the scan but before 12 weeks gestation. Logistic regression analysis was used to create a prediction model for miscarriage prior to 12 weeks gestation based on the standardised ultrasound measurements recorded during the early first-trimester scan.

RESULTS

Comparison of Z-Scores for meanUAPI, TTV, FHR and MSD demonstrated significant variation between the two groups. The proposed logistic regression model resulted in an area under the receiver operator curve of 0.81. At a false-positive rate of 30%, the model resulted in a sensitivity of 76% (95% CI 64-89%).

CONCLUSION

The combination of FHR, meanUAPI, TTV in a prediction model for miscarriage may prove to be of value for ongoing pregnancy management in the first trimester.