Objectives: To quantitatively examine placental tissue elasticity in Trisomy 21 (T21) pregnancies using shear wave elastography (SWE) and to evaluate the potential contribution of placental SWE measurements in predicting T21 fetuses. Methods: This prospective case-control study was conducted at tertiary centers between January 2022 and January 2024. The study included 30 pregnant women who underwent invasive prenatal diagnostic testing and were found to have T21, along with 30 pregnant women with a normal karyotype. Central placental elasticity measurements were performed from the middle of the thickest part of the placenta, avoiding vascular areas and lacunae, and peripheral measurements were performed two centimeter (cm) medial to the lateral border of the placenta. Results: The mean gestational week at measurement was 16 ± 2 weeks. Peripheral placental SWE velocity was significantly higher in the T21 group (7.4 ± 3.7 kPa vs. 4.8 ± 3.6 kPa, p=0.004). Similarly, central placental SWE velocity was also significantly higher in the T21 group (6.5 ± 2.1 kPa vs. 4.1 ± 2.6 kPa, p<0.001). In predicting T21, central placental SWE velocity had 76.7 % sensitivity and 73.3 % specificity with a cut-off value of ≥4.35 kPa (p<0.001), and peripheral had 70 % sensitivity and 66.7 % specificity with a cut-off value of ≥4.65 kPa (p=0.004). When central placental SWE velocity was ≥4.35 kPa, the risk of T21 was increased 6.64-fold, even after adjusting for maternal age, which is a well-known risk factor for T21. Conclusions: Placental stiffness was significantly higher in T21 in both central and peripheral areas. Placental elasticity, especially in the central part, may be a potential marker for T21.

Objectives: This study aimed to assess the diagnostic contribution of fetal MRI across different anatomical systems and evaluate its added value beyond prenatal ultrasonography. Methods: This retrospective cohort included 556 fetuses who underwent both prenatal ultrasound and fetal MRI in a single tertiary center. Cases were classified by anatomical system. The concordance between ultrasound and MRI findings, as well as additional or ruled-out findings identified by MRI, was analyzed. Statistical significance and clinical relevance were also evaluated. Results: Among the 556 cases, complete concordance between ultrasound and MRI findings was observed in 48.9%. MRI ruled out the initial diagnosis in 20.1% and revealed additional findings in 32% of cases. A total of 192 additional findings were identified, while 115 previously suspected anomalies were ruled out. The highest diagnostic contribution was observed in central nervous system (CNS) and gastrointestinal system (GIS) anomalies. Posterior fossa abnormalities and cystic or mass lesions were frequently detected as additional findings on MRI. In contrast, ultrasound alone was generally sufficient for evaluating genitourinary (GUS), thoracic, and vertebral anomalies. The overall diagnostic yield of MRI was higher in anatomically complex or sonographically ambiguous cases. Conclusions: Fetal MRI provides significant additional diagnostic value, particularly in CNS and GIS anomalies, by detecting additional findings, clarifying uncertain diagnoses, or excluding suspected anomalies. Its selective use may enhance both prenatal counseling and postnatal management.

Background/Objectives: Maternal thyroid function plays a crucial role in fetal brain development, yet the potential impact of maternal hypothyroidism and thyroid autoimmunity on fetal intracranial structures remains inadequately explored. To investigate the impact of maternal hypothyroidism and thyroid autoimmunity on fetal intracranial structures, focusing on potential alterations in critical brain parameters during mid-gestation. Methods: This prospective case-control study included pregnant women between 18 and 24 weeks of gestation. Participants were divided into three groups: hypothyroidism and antibodies (Ab) group, hypothyroidism and Ab(–) group, and the control group. Ultrasonographic measurements of fetal intracranial structures such as the posterior lateral ventricle (PLV), cavum septum pellucidi (CSP), cisterna magna (CM), thalamus, and transcerebellar diameter (TCD) were recorded and compared. Results: A total of 153 pregnant women were evaluated (n = 52 in the hypothyroidism and Ab(+) group, n = 51 in the hypothyroidism and Ab(−) group, and n = 50 in the control group). Although most of the biometric parameters were similar across the groups, the hypothyroidism and Ab(+) group exhibited significantly lower PLV and thalamus measurements compared to the control group (p < 0.05). Additionally, there was a notable difference in the BMI among the groups, with hypothyroid participants (with or without antibodies) showing higher rates of being overweight or obese. Conclusions: Maternal hypothyroidism and the presence of thyroid autoantibodies may be associated with subtle changes in fetal brain structures during the mid-gestation period, particularly in the thalamus and PLV.

To evaluate the incidence, prenatal findings, and pregnancy outcomes of rare autosomal trisomies (RATs). This retrospective cohort study included cases diagnosed via chorionic villus sampling, amniocentesis, or fetal cord blood sampling. Data collected included maternal demographics, gestational age, first-trimester screening results, ultrasound findings, genetic analyses, and pregnancy outcomes. A total of 354 cases of common trisomies and 18 cases of RATs (trisomies 2, 5, 7, 8, 9, 12, 20, and 22) were identified. Common trisomies were associated with higher maternal age (p = 0.003) and advanced maternal age rates (≥35 years) (p = 0.009). Fetal (61.1% vs. 1.7%) and confined placental mosaicism (22.2% vs. 0.3%) were significantly more frequent in RATs (p < 0.001, for all). Ultrasound anomalies were observed in 11 of 18 (61.1%) RATs, with trisomy 22 frequently involving craniofacial and cardiac abnormalities. RATs display diverse clinical outcomes. Mosaicism and ultrasound findings are critical for assessing prognosis and guiding clinical management.