The June issue of Ultrasound in Obstetrics & Gynecology includes an article on the available evidence regarding intrauterine vertical transmission of SARS-CoV-2, studies on the cost-effectiveness of prenatal screening strategies for congenital heart defects and reasons for a missed diagnosis, with an accompanying Editorial, a study on the role of Doppler ultrasound at the time of diagnosis of late-onset fetal growth restriction in predicting adverse perinatal outcome, a study presenting diagnostic criteria for T-shaped uterus, and updated ISUOG Interim Guidance on COVID-19 during pregnancy and puerperium.

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

Intrauterine vertical transmission of SARS-CoV-2: what we know so far

During the current COVID-19 pandemic, a major concern is whether SARS-CoV-2 can be vertically transmitted from mothers to their fetuses. Wang et al. evaluate the existing data, which show that, in women infected in the late third trimester, there is no evidence of intrauterine infection caused by vertical transmission. However, it is possible that a longer time interval from clinical manifestation of COVID-19 to delivery may increase the risk of vertical transmission, and there appear to be mechanisms by which transplacental vertical transmission could potentially occur. In order to determine whether SARS-CoV-2 can be transmitted in utero, the authors advise that cohort studies including women infected in the first or second trimester are required, with collection of appropriately matched biological samples immediately after delivery, using aseptic technique, serological testing and longitudinal follow-up of infants 6–18 months after birth.

Fetal cardiac evaluation services for low-risk pregnancies: how can we improve?

In the context of the findings of two articles in this issue of the Journal, Yagel and Moon-Grady discuss the current state of prenatal screening for congenital heart defects (CHD) and how it may be improved. Over the last three decades, the short-axis-planes approach to fetal-heart scanning, including the axial four-chamber (4C), right (RVOT) and left (LVOT) ventricular outflow tract, three-vessel (3V) and three-vessels-and-trachea (3VT) views, has gradually become standard practice in fetal medicine. Bak et al. demonstrated that cost-effectiveness is maximized when all of these views are included as part of routine prenatal care. van Nisselrooij et al. explored factors associated with a missed prenatal diagnosis of CHD on the second-trimester standard anomaly scan, including the 4C, 3V, RVOT and LVOT views, finding that the quality of the cardiac planes obtained, rather than circumstantial factors, plays an important role in the prenatal detection of CHD, which can be improved by increasing the volume of examinations performed. Yagel and Moon-Grady note that some of the missed lesions may have been amenable to diagnosis with the addition of the 3VT view, and conclude that, based on these findings, it may be time to update fetal screening guidelines to include recommendations for incorporating the 3VT view and for ongoing auditing of sonographers.

Role of Doppler ultrasound at time of diagnosis of late-onset fetal growth restriction in predicting adverse perinatal outcome: prospective cohort study

Pregnancies complicated by late-onset fetal growth restriction (FGR) are at increased risk of short- and long-term morbidities. Despite this, identification of cases at higher risk of adverse perinatal outcome, at the time of FGR diagnosis, is challenging. Rizzo et al. evaluated the association between fetoplacental Doppler indices at the time of diagnosis of late-onset FGR and adverse perinatal outcome. It was found that only umbilical vein blood flow normalized by abdominal circumference showed moderate accuracy in predicting adverse perinatal outcome, while the diagnostic performances of both cerebroplacental ratio and uterine artery pulsatility index were low (view the accompanying Journal Club slides).

Congenital Uterine Malformation by Experts (CUME): diagnostic criteria for T-shaped uterus

The prevalence, clinical relevance and appropriateness of management of T-shaped uterus are not fully understood, due to the lack of objective criteria for its diagnosis. Ludwin et al. developed an objective definition of T-shaped uterus using CUME methodology. It was found that the agreement among experts in the diagnosis of T-shaped uterus was only moderate and the judgement of individual experts was commonly insufficient for accurate diagnosis. Three uterine morphometric measurements in the coronal plane were identified, with cut-offs (lateral internal indentation depth ≥7mm, lateral indentation angle ≤130° and T-angle ≤40°) that have good diagnostic test accuracy and fair-to-moderate reliability for the diagnosis of T-shaped uterus. In the absence of other anomalies, the authors suggest considering a uterus to be normal when no or only one criterion is met, borderline when two criteria are met, and T-shaped when all three criteria are met.

ISUOG Interim Guidance on coronavirus disease 2019 (COVID-19) during pregnancy and puerperium: information for healthcare professionals – an update

Pregnant women require special attention in relation to prevention, diagnosis and management of COVID-19. Based on the available information and knowledge of other similar viral pulmonary infections, updated ISUOG Interim Guidance offers expert opinions to guide clinical management of COVID-19 during pregnancy and puerperium. Areas covered include lung ultrasound, triage of pregnant women, referral to the intensive care unit, and neonatal impact and care.

Coming up next month…

  • ISUOG Practice Guidelines on the role of ultrasound in congenital infection. Read them now on Early View.
  • Systematic review of 266 pregnancies on the effects of COVID-19 on maternal, perinatal and neonatal outcomes. Preview the Accepted Article.
  • RCT on preoperative pelvic floor muscle training. Preview the Accepted Article.
  • Case series demonstrating clinical role of lung ultrasound in pregnant women with  COVID-19. Preview the Accepted Article.