Utility Of Transvaginal Sonography With Extended Examination For Fetal Anatomical Survey During 11-13+6 Weeks Of Pregnancy

Abstract

Introduction: The 11–14 week period of pregnancy is a crucial window for detailed fetal anatomical assessment, as major organ systems begin to form, making it ideal for early detection of congenital anomalies through ultrasound. Technological advancements, particularly in high-resolution transvaginal scanning, have greatly enhanced the accuracy of first-trimester evaluations, making early ultrasound a key tool in prenatal care for diagnosing abnormalities, guiding parental counseling, and improving pregnancy outcomes.

Methods: This is prospective analytical study conducted at the Department of Obstetrics and Gynecology, Adichunchanagiri Institute of Medical Sciences, Adichunchanagiri University,  B G Nagara, Mandya, Karnataka, India for duration of 18 months from May 2023 to December 2024, comprising of 200 subjects.

Results: The transvaginal scan seems to be slightly better at visualizing most body parts compared to the transabdominal scan, especially for the face, spine, kidneys, and bladder. Transvaginal scans generally provide better visualization for most structures in smaller CRL ranges compared to transabdominal scans. a total of 3 cases of unossified nasal bone and  5 cases of fetal anomalies(4%), i.e. 1 case of right club foot, 1 case of cystic hygroma, 1 case of anencephaly, 1 case of acrania-anencephaly sequence and 1 case of acrania- exencephaly sequence were identified during study.

Conclusion: While both TAS and transvaginal ultrasound (TVS) are effective in visualizing fetal structures, TVS offers slightly better detection of key anatomical features and serves as a valuable complementary tool, especially when TAS is limited.