The March issue of Ultrasound in Obstetrics & Gynecology includes a study evaluating the cost-effectiveness of performing an ultrasound assessment before cell-free DNA analysis for fetal aneuploidy screening, a study investigating the impact of prenatal exome sequencing on perinatal outcome, a prospective study assessing the potential of lower uterine segment thickness in identifying women at risk of Cesarean delivery following labor induction, and a systematic review and meta-analysis assessing the diagnostic accuracy of individual ultrasound signs for detecting adnexal torsion.

Please see below a selection of articles from the March issue of the Journal chosen specially by the UOG team. To view all UOG content, become an ISUOG member today or login and upgrade.

Cost-effectiveness of ultrasound before non-invasive prenatal screening for fetal aneuploidy

Cell-free DNA (cfDNA) screening has been validated as an acceptable and superior method of fetal aneuploidy screening. In contrast to standard first-trimester screening based on maternal serum analyte testing and nuchal translucency thickness, cfDNA screening does not require an ultrasound examination to obtain a result. However, first-trimester ultrasound remains a key component of routine prenatal care and can be useful prior to cfDNA screening in certain situations. In this study, Battarbee et al. demonstrate that first-trimester ultrasound prior to a cfDNA test is a more cost-effective strategy for non-invasive prenatal aneuploidy screening compared with cfDNA testing alone. The authors recommend performing fetal ultrasound prior to cfDNA fetal aneuploidy screening to prevent unindicated testing, improve interpretation of results and minimize delay in care caused by inappropriate screening.

Prenatal exome sequencing and impact on perinatal outcome: cohort study

Rapid prenatal exome sequencing (pES) is a powerful novel tool in prenatal diagnostics that can provide parents with a definitive genetic diagnosis and important information to help evaluate their options for the pregnancy, plan neonatal care and consider the risk of recurrence. In this study, Poljak et al. evaluate the impact of pES performed as part of the UK NHS R21 pathway on perinatal outcome. Their findings suggest that significantly more women opt for late termination of pregnancy following identification of a causative variant by pES compared with when the pES result is uninformative. The authors believe that, as the R21 pathway continues to evolve, collaborative work between fetal medicine and clinical genetics teams and development of resources to support couples should be prioritized, and urge clinicians and policymakers to consider earlier fetal anomaly screening.

Lower uterine segment thickness assessed by transvaginal ultrasound before labor induction: reproducibility analysis and relationship with delivery outcome

Induction of labor (IOL) is one of the most common procedures in obstetrics and is associated with a 20–30% risk of unplanned Cesarean delivery. Previous studies have evaluated lower uterine segment (LUS) thickness as a predictor of IOL outcome. In this prospective study of 265 women, Del Campo et al. evaluate whether LUS thickness can predict the type of delivery following IOL, showing that it is strongly associated with Cesarean section for any indication after IOL and specifically with Cesarean section for failed IOL. They also demonstrate that LUS thickness measurement has excellent interobserver reproducibility and can be performed easily on transvaginal ultrasound. These findings confirm that LUS thickness can act as a useful marker for identifying women at risk of Cesarean delivery after IOL.

Diagnostic accuracy of ultrasound signs for detecting adnexal torsion: systematic review and meta-analysis

Adnexal torsion accounts for about 3% of all gynecological emergencies. Ultrasound plays an important role in the correct diagnosis of adnexal torsion and is considered to be the imaging modality of choice. The systematic review and meta-analysis by Garde et al. is the first to provide a comprehensive analysis of the diagnostic accuracy of multiple classic ultrasound signs of adnexal torsion. The findings of the study suggest that the presence of an adnexal mass and pelvic fluid have poor diagnostic accuracy as ultrasound markers of adnexal torsion, while ovarian edema, the whirlpool sign and decreased or absent ovarian Doppler flow have good specificity but moderate sensitivity for detecting adnexal torsion. Given the modest performance of the evaluated markers, future research should focus on creating a scoring system combining several clinical features and ultrasound findings in order to improve the diagnostic performance for adnexal torsion.

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Coming up next month…

  • A systematic review and meta-analysis evaluating the effectiveness and safety of prenatal valacyclovir for congenital cytomegalovirus infection. Preview the Accepted Article.
  • A population-based cohort study of 266,440 uncomplicated pregnancies evaluating the relationship between birth-weight percentile and school performance. Preview the Accepted Article.
  • A modified Delphi study of ultrasound signs for detecting placenta accreta spectrum. Preview the Accepted Article.