Prenatal Ultrasound Diagnosis of Sirenomelia Sequence in First Trimester: A Case Report.

This case report describes a prenatal diagnosis of sirenomelia sequence at 12 weeks and 4 days of gestation using two-dimensional (2D) and three-dimensional (3D) ultrasound. The case highlights the importance of First Trimester ultrasound screening and the value of 3D ultrasound in early diagnosis. The etiology of this condition is discussed, with a focus on its potential association with embryonic layer development abnormalities. Ultimately, the patient opted for termination of pregnancy. This report provides valuable clinical experience in the early ultrasound diagnosis of sirenomelia sequence and discusses the importance of its ultrasound manifestations and clinical management.