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Nascent Expectations and Hope
Published in Michael van Manen, The Birth of Ethics, 2020
On the one hand, we can blame medical technologies whereby we recognize they inherently make the calculation of risk possible; it is as if the technologies themselves bear moral responsibility (Verbeek, 2011). On the other hand, such technologies and how they are integrated into clinical practice reflect an ethics of technology application. For example, ultrasound makes it possible to suspect a genetic diagnosis. ‘Soft markers’ such as nonossified nasal bone, linear arrangement of the tricuspid and mitral valves within the heart, thickened nuchal skin fold, relatively short humerus or femur compared to head size, echogenic intracardiac focus, fetal hydronephrosis, and so forth are all associated with aneuploidy (abnormal chromosome number) (Norton, 2013). Similarly, biochemical measures from the expectant mother’s blood or urine, such as free beta human chorionic gonadotropin (FbhCG) and pregnancy-associated plasma protein A (PAPP-A), also have clear associations with genetic conditions (Tørring, 2016). When we combine maternal age, ultrasound findings, and biochemical values, further refinement of probability for aneuploidy can be calculated to determine risk (Alldred et al., 2017). From the determination of risk, either chorionic villus sampling or amniocentesis may be offered for more definitive diagnostic testing, recognizing such tests have risks in themselves: precipitation of labor, needle injury to the fetus, and infection transmission. Alternatively, cell-free DNA detection methods for non-invasive prenatal testing (NIPT) are available such that genetic conditions may be identified with a high degree of certainty through analysis of tiny amounts of fetal DNA circulating in the expectant mother’s blood (such as the above mentioned Harmony Prenatal Test) without the risks of pregnancy loss (Dondorp et al. 2016; Morain et al. 2013). To be clear, lack of invasiveness describes physiologic invasiveness relative to chorionic villus sampling or amniocentesis.
Second-trimester screening for fetal abnormalities
Published in Hung N. Winn, Frank A. Chervenak, Roberto Romero, Clinical Maternal-Fetal Medicine Online, 2021
Jolene C. Muscat, Anthony M. Vintzileos
The fetal thorax and visceral contents are imaged next. The diaphragm is examined for evidence of diaphragmatic hernia. Fetal lung echogenecity should be homogeneous to exclude mass or tumor such as cystic adenomatoid malformation. Any pleural effusion or evidence of pulmonary hypoplasia is considered abnormal. Fetal cardiac examination should then follow. American Institute of Ultrasound in Medicine practice guidelines for basic cardiac examination include a four-chamber view of the fetal heart and, if technically feasible, views of both outflow tracts. However, a more comprehensive cardiac evaluation may be needed to exclude some fetal cardiac abnormalities. To begin, cardiac rate and rhythm should be documented. Cardiac size should be measured and is expected to be approximately one-third of the fetal thorax. The cardiac apex should point to the left at an angle of 45 ± 20 degrees relative to the midline. Normal situs should be established with fetal liver on the right and stomach on the left. A four-chamber apical view should be obtained with all chambers being approximately equal in size (Fig. 9). There should be no pericardial fluid or collection. An intact intraventricular and intra-atrial septum excludes the presence of ventricular septal defect and atrial septal defect respectively. The outflow tracts, aortic arch, ductal arch, and inferior and superior vena cava should be identified. An echogenic intracardiac focus (EIF), most commonly seen in the left ventricle, can occur in up to 5% of normal pregnancies (19). It is typically caused by a specular reflection secondary to mineralization within the papillary muscles (20,21). Because it is seen in approximately 13% to 18% of pregnancies complicated by Down syndrome, presence of an EIF has traditionally been utilized by some investigators as a sonographic marker to modify a woman’s a priori risk of fetal aneuploidy (22–24). However, more recent literature suggests that when an EIF is seen as an isolated finding in an otherwise normal fetal anatomy survey, it is more likely to be a normal variant (25,26). This will be further discussed later in the chapter.
Could high levels of cell-free DNA in maternal blood be associated with maternal health and perinatal outcomes?
Published in Journal of Obstetrics and Gynaecology, 2020
Bahar Konuralp Atakul, Altug Koc, Duygu Adiyaman, Melda Kuyucu, Alkim Gulsah Sahingoz Yildirim, Merve Saka Guvenc, Kadri Murat Erdogan, Baris Sengul, Deniz Can Oztekin
This study was conducted in the Maternal-Foetal Medicine Unit of Health Sciences University, İzmir Tepecik Training and Research Hospital. The indications of non-invasive prenatal screening test named as ‘Tepecik Criteria’ were defined by maternal-foetal medicine unit since there was no nationally accepted NIPT screening guideline in Turkey. Indications for NIPT were advanced maternal age (≥ 35 years), in first- trimester screening tests having a combined risk of trisomy 21 risk between 1/300-1/1000, in second trimester screening tests having a biochemical risk more than 1/1000 or having one soft marker including pyelectasis, echogenic intracardiac focus and choroid plexus cysts on second-trimester foetal ultrasonography for trisomy 21. Patients with the major foetal anomaly, the strongest soft markers on second-trimester foetal ultrasonography for trisomy 21, multiple pregnancies, vanishing twin, having BMI ≥35, history of blood transfusion, transplantation and maternal malignancy were excluded. The drawing was performed before the next injection when the plasma level was expected to be the lowest in patients using low-molecular-weight heparin (LMWH) treatment. We compared maternal characteristics, prenatal results and perinatal outcomes of 112 women with high levels of cfDNA with 112 women with normal levels of cfDNA. Pregnant women selected as control group among 4369 patients with normal cfDNA were randomly selected. Controls and cases were matched to gestational age to avoid a possible confounding factor since the concentration of foetal cfDNA increased with the gestational age. This protocol was approved by ‘Izmir Tepecik Training and Research Hospital Local Ethical Committee’.
Complementary Approaches in Fetal Genetic Diagnosis: Decision-Making Process and Alternative Choices for Clinicians in a Secondary Health Care Institution
Published in Fetal and Pediatric Pathology, 2022
Hilmi Bolat, Hamide Betül Gerik Çelebi, Ertuğrul Karahanoğlu
The most common ultrasound abnormalities that were indicated for invasive prenatal testing were nuchal fold thickness (155/373, 41.6%), hyperechogenic bowel (55/373, 14.7%), echogenic intracardiac focus (40/373, 10.7%), and pyelectasis (30/373, 8.0%) (Table 2).