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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, METHODS, RESULTS. Meshes: Adult, Blood Grouping and Crossmatching, Computer Systems, DNA, Decision Making, Erythroblastosis, Fetal, Female, Fetal Blood, Fetomaternal Transfusion, Genotype, Humans, Infant, Newborn, Isoantibodies, Polymerase Chain Reaction, Pregnancy, Prenatal Diagnosis, Prospective Studies, Rh-Hr Blood-Group System, Rho(D) Immune Globulin, Sensitivity and Specificity, Unnecessary Procedures.
user
Is the determination of the fetal D status from maternal plasma for decision making on Rh prophylaxis feasible? Context: Noninvasive fetal RHD genotyping might become a valuable tool in decision making on antenatal Rh prophylaxis, which is currently in routine practice for all D- pregnancies in several countries. This study provides a large-scale validation study of this technology to address questions concerning feasibility and applicability of its introduction into clinical routine. Real-time polymerase chain reaction (PCR) targeting RHD Exons 5 and 7 was applied for the detection of fetal-specific RHD sequences in maternal plasma. A total of 1113 women in 6 to 32 weeks (median, Week 25) of pregnancy were recruited. All of them were serologically typed as D- according to current German guidelines. DNA was extracted via a spin-column method and a novel automated approach using magnetic tips. Real-time PCR results were compared with postnatal serology and discrepancies further elucidated by DNA sequencing from a newborn's buccal swab. Sensitivities of fetal RHD genotyping were 99.7 percent (spin columns) and 99.8 percent (magnetic tips), thus comparable with serology (99.5%). The detection of weak D variants was more reliable by real-time PCR. Specificities of fetal RHD genotyping were 99.2 percent (spin columns) and 98.1 percent (magnetic tips), which is lower than serology (>99.7%). Automation achieved significantly higher yields of cell-free fetal DNA.
assistant
This prospective clinical trial revealed that routine determination of the fetal D status from maternal plasma is feasible. Noninvasive fetal RHD genotyping can be considered as sensitive as the traditional postnatal serologic assay. Final Decision: yes