The January issue of Ultrasound in Obstetrics & Gynecology includes a systematic review on the accuracy of cell-free fetal DNA in detecting chromosomal anomalies in women experiencing miscarriage, a study evaluating the predictive performance of the 36-week scan for small-for-gestational age, a Delphi consensus study reporting the critical procedural steps for intrauterine transfusion and a cost-effectiveness study assessing the clinical value of preimplantation genetic testing for aneuploidy.
Please see below a selection of articles from the January issue of the Journal chosen specially by the UOG team. To view all UOG content, become an ISUOG member today or login and upgrade.
Accuracy of cell-free fetal DNA in detecting chromosomal anomalies in women experiencing miscarriage: systematic review and meta-analysis
Since 50–70% of miscarriages are estimated to be due to fetal aneuploidy or genetic anomaly, identifying a potential genetic cause is crucial for the management of a future pregnancy. Della Valle et al. conducted a systematic review and meta-analysis to ascertain the value of cell-free fetal DNA (cfDNA)-based techniques in detecting aneuploidy in women experiencing miscarriage. cfDNA screening was found to have a high diagnostic accuracy for fetal trisomies 21, 18 and 13, with a sensitivity of 100%, 100% and 88.9%, respectively, and specificity of 100% for all. However, diagnostic accuracy for other aneuploidies and copy-number variants was only moderate and the authors concluded that cytogenetic assessment of pregnancy tissue still exhibits superior performance.
Routine 36-week scan: prediction of small-for-gestational-age neonate
Small-for-gestational age (SGA) screening is achieved typically by sonographic fetal biometry to determine the estimated fetal weight (EFW), but there is mixed evidence on how to attain the best predictive performance. Adjahou et al. evaluated and compared the predictive performance of routine ultrasonographic EFW at 32 vs 36 weeks for SGA in a large cohort of 129 551 women. Amongst other factors, screening for SGA had higher predictive performance when the scan was carried out at 35 + 0 to 36 + 6 weeks’ gestation, when the outcome measure was birth weight < 3rd percentile and when prediction was performed using a model that combined maternal risk factors with EFW to estimate the individual patient-specific risk. These findings lend further support to previous similar studies.
Critical procedural steps in intrauterine transfusion: Delphi survey of international experts
Intrauterine transfusion (IUT) of donor red cells is the accepted standard of care for fetal anemia, but significant variation in preparation of the blood products and performance of the procedure between centers has been identified. Moise et al. conducted an international Delphi study of 49 experts to reach consensus regarding the critical procedural steps for IUT during pregnancy. Twenty procedural steps were deemed critical, with the highest ranking steps including: preoperatively, obtaining informed consent and having an experienced operator perform the procedure; intraoperatively, calculating the specific volume of blood to transfuse at the start of the procedure; and postoperatively, undertaking continuous fetal heart-rate monitoring once gestational age has surpassed the viability threshold. The authors indicate that these findings can be adopted in clinical practice to standardize the approach to performing IUT.
Value of PGT-A when only one or two blastocysts are obtained: propensity-score matching and cost-effectiveness study
In women undergoing in-vitro fertilization (IVF), pre-implantation genetic testing for aneuploidy (PGT-A) has become an increasingly popular technique used to identify embryos that are unsuitable for transfer; however, the cost of PGT-A is high and therefore its clinical value is debated in cases where only one or two blastocysts are obtained. In this study, Cimadomo et al. compared the effectiveness of IVF with and without PGT-A and demonstrate that PGT-A reduces the time taken to conclude an IVF cycle and reduces the number of embryo transfers and miscarriages, while the cumulative live birth rate per patient remains unaffected. The authors report that these advantages outweigh the associated costs and future studies should include a randomized controlled trial to confirm the clinical value and cost-effectiveness of PGT-A in a larger, more diverse dataset.