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Introduction: Absent or hypoplastic nasal bone (NB) is a soft marker for aneuploidy. It is said to be absent when it is not visualised , or is less than 2.5mm in size in the second trimester. Aims and Objectives: To study the etiology and outcomes of fetuses diagnosed with absent nasal bone on mid trimester antenatal scans over a one year period Material and Methods: This retrospective study was conducted at the Fetal Medicine Unit of the Christian Medical College and Hospital, vellore between June 2023 to June 2024. All pregnant women whose fetuses were diagnosed with absent or hypoplastic nasal bone(NB) during antenatal scans were included in the study. The outcomes assessed were the spectrum of chromosomal abnormalities associated with this condition and the subsequent outcomes of these babies. Results: In our study of 24 fetuses with absent nasal bone, the mean maternal age was 26 years, with two mothers over 35. Combined first-trimester screening (CFTS) was available for only three women (12.5%). Significantly, two-thirds of the fetuses (18 out of 24, or 67%) had related abnormalities. Half of the participants (13/24) underwent prenatal invasive testing; among these, six fetuses (46%) had abnormal karyotypes, with Trisomy 21 being the most common chromosomal abnormality, found in two cases (33%) Conclusion: Among fetuses with absent nasal bone who underwent evaluation, two-thirds had associated anomalies. The distribution of abnormal karyotypes was nearly equal between isolated and associated groups; however, only half of those with associated findings (9 out of 16, or 56%) were evaluated. The percentage of abnormal karyotypes would have been higher if more cases in the associated group had been evaluated. Those with isolated findings and abnormal karyotypes had minor abnormalities, such as mixoploidy and Klinefelter syndrome.