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Shahida Hashim Marwat
Saima Nadeem
Sumaiya Khan
Madiha Afzal
Uzma Aziz
Kailash Kumar Daseja
Abdulla K. Alsubai
Akashnath Kivalur Ganeshanath
Hafsa Syeda Shuaib
Zacarius William Seit


Prenatal testing, non-invasive screening, high-risk pregnancies


Introduction: Maternal-fetal health is a critical facet of prenatal care, with advancements in screening technologies continually shaping the landscape of diagnostic approaches. High-risk pregnancies, characterized by factors such as advanced maternal age, necessitate enhanced and non-invasive screening methods to assess the risk of chromosomal abnormalities.

Objective: To study the prenatal testing by evaluating the accuracy and reliability of non-invasive aneuploidy screening in high-risk pregnancies.

Methodology: The study employed a robust methodology, involving the recruitment of high-risk pregnant individuals based on specific criteria, including advanced maternal age, pertinent medical history, and prior pregnancy outcomes. Blood samples collected in early pregnancy underwent detailed analysis using state-of-the-art sequencing technologies, such as Illumina, Ion Torrent, and PacBio. Statistical analyses, including sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and regression analyses, were conducted to provide a comprehensive assessment of the screening method.

Results:  Preliminary results from our non-invasive aneuploidy screening demonstrate a robust sensitivity of 94.2%, specificity of 96.8%, positive predictive value (PPV) of 89.5%, and negative predictive value (NPV) of 97.3%. Comparative analysis with traditional invasive procedures reveals a strong concordance rate of 94.7%, validating the efficacy of the non-invasive approach. In terms of cost-effectiveness, the total test costs amount to Rs. 412,500, with anticipated healthcare savings of Rs. 1,375,000. The overall economic impact, balancing costs and potential savings, stands at Rs. 962,500. Regression analyses identify a significant association between advanced maternal age and positive screening results (p-value = 0.021), providing essential insights for personalized risk assessment in high-risk pregnancies. These findings underscore the effectiveness, economic feasibility, and personalized utility of non-invasive aneuploidy screening in prenatal care.

Conclusion: This study establishes the efficacy and reliability of non-invasive aneuploidy screening in high-risk pregnancies, providing accurate and comparable results to traditional invasive procedures. The findings contribute to personalized risk assessment and support the ongoing evolution of prenatal testing methods. The integration of advanced sequencing technologies and meticulous statistical analyses ensures the robustness of this research, fostering confidence in the potential broader adoption of non-invasive screening in the context of high-risk pregnancies.


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