Simcha Yagel

Early applications of fetal Doppler evaluation drew on parameters derived from adult vascular examination, primarily applied to identifying fetuses at risk for growth restriction and hypoxia. The integration of color Doppler into real-time imaging facilitated a shift toward structural-functional correlation, enabling clinicians to visualize fetal cardiac outflow tracts, valve regurgitant jets, and the complex umbilical–venous connections alongside standard grayscale anatomy. Power Doppler extended these capabilities to slow flow and small caliber vascular structures. Doppler modalities have been crucial in delineating the fetal cardiovascular system, increasingly detecting complex congenital heart disease (CHD) prenatally, and illuminating cardiac and non-cardiac vascular structures that previously posed a challenge to visualization, including cerebral, hepatic, and placental capillary beds. Highly sensitive Doppler technologies such as Slow flow HD as well as MV-Flow and LumiFlow, exemplify the convergence of anatomical and physiological imaging, such as fetal venous sinuses and deep cerebral venous return, to allow brain perfusion assessment at earlier gestational stages. Although Slow flow HD has been shown to have added value for diagnosis, it seems to be an underused modality. Here we show several examples drawn from our experience with Slow flow HD, in both routine scanning and anomalous cases spanning various organ systems and stages of gestation. While there is a learning curve in optimizing image acquisition and interpretation of microvascular anatomy, it should not deter practitioners proficient in Doppler techniques. We recommend incorporation of Slow flow HD and comparable microvascular imaging technologies into the sonographic armamentarium.

Introduction: Optimal timing of final intrauterine transfusion (IUT) and delivery in fetal anemia remains controversial, balancing procedural risks against prematurity complications. Our objective is to evaluate the safety and effectiveness of extending IUT beyond 34 weeks gestation in appropriately selected cases.Methods: Retrospective cohort study comparing pregnancies receiving late IUT (≥34 weeks, n = 21) versus early IUT (n = 31) at a single tertiary center (2005–2024). We analyzed 200 IUT procedures in 52 pregnancies. Late IUT was offered to stable cases without hydrops or previous significant complications. Primary outcomes included procedure-related complications and prematurity-related outcomes.Results: Late IUT showed no increase in procedure-related complications (0% vs. 20.0%, p = 0.069). Mean gestational age at delivery was higher in the late IUT group (37.2 ± 1.06 vs. 34.1 ± 3.6 weeks, p < 0.001), with reduced emergency cesarean rates (19% vs. 45%), higher birth weights (2,960 ± 399 g vs. 2,350 ± 620 g, p < 0.001), and lower NICU admission rates (29% vs. 71%, p < 0.05). These benefits persisted after adjusting for maternal characteristics. Subgroup analysis of hemolytic disease cases showed similar improvements with additional benefits in neonatal outcomes.Discussion: Extending IUT beyond 34 weeks in selected cases is safe and associated with improved obstetric and neonatal outcomes, supporting reconsideration of traditional gestational age limits for IUT.

Objectives: First‐trimester ultrasound has evolved to incorporate a detailed fetal anatomy scan (FAS) with nuchal translucency (NT) screening. Many institutions use a 2‐visit protocol: NT followed by detailed FAS at 14–16 weeks. We aimed to evaluate whether integrating detailed FAS into the NT window (12 + 5 to 13 + 6 weeks) is non‐inferior in diagnostic yield to the 2‐visit protocol. Methods: We enrolled 755 mixed high‐ and low‐risk pregnant women with singleton gestations into either integrated NT + FAS group (n = 243, 12 + 5 to 13 + 6 weeks) or 2‐visit group (n = 512, 14–16 weeks). All underwent follow‐up at 20–24 weeks. Scans followed ISUOG guidelines; the primary outcome was detection of fetal anomalies during detailed early scans. Non‐inferiority was defined as a margin of ≤6% difference in detection rates. Results: Study groups were similar except in parity (mean 2.6 [0–9] vs. 3.1 [0–10], P = .0081 in FAS + NT and 2‐visit group, respectively). Anomalies were identified in 16 fetuses (7.5%) in the NT + FAS group and 16 (3%) in the 2‐visit group ( P = .033). Additional anomalies were detected at mid‐trimester in 2/227 (0.9%) NT + FAS and 4/496 (0.8%) 2‐visit group fetuses ( P = 1.0). The integrated approach met non‐inferiority criteria. Conclusion: Detailed FAS during the final NT window week is non‐inferior to the 2‐visit approach. This integrated protocol offers earlier reassurance without compromising diagnostic accuracy.

The immune compartment of the maternal-fetal interface must balance between supporting maternal-fetal interactions and maintaining maternal tolerance. Despite recent advances, the cellular and molecular regulators that drive maternal immune cell remodeling remain largely unknown. Using index and transcriptional single-cell sorting, we comprehensively characterized the immune compartment dynamics in the maternal-fetal interface of both human and mouse and charted the markers and functional pathways associated with these cells. Comparing immune signatures in decidua and tumors of human and mice, we identify conserved gene modules that are activated in natural killer (NK) cells of both compartments, including TFG-β signaling. Genetic ablation and antibody blockade of the TGF-β pathway in NK cells resulted in enhanced anti-tumor immunity.