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Updated: May 20, 2026
06:59
Image Acquisition Method for the Sonographic Assessment of the Inferior Vena Cava
Published on: January 13, 2023
Vasa previa is not infrequent
Junichi Hasegawa1, Masamitsu Nakamura, Kiyotake Ichizuka
1Department of Obstetrics and Gynecology, Showa University School of Medicine, Tokyo, Japan. hasejun@oak.dti.ne.jp
Summary
Ultrasonography can identify vasa previa (a rare placental condition) in the first trimester. This study found vasa previa to be more common than previously thought, recommending early screening for umbilical cord abnormalities.
Area of Science:
- Perinatology
- Fetal Medicine
- Diagnostic Ultrasound
Background:
- Vasa previa is a rare obstetric complication where fetal blood vessels cross the internal cervical os.
- The condition is associated with significant fetal and neonatal morbidity and mortality.
- Accurate diagnosis is crucial for timely intervention.
Purpose of the Study:
- To determine the frequency of vasa previa using first-trimester ultrasonography.
- To evaluate the efficacy of early ultrasound in diagnosing vasa previa.
- To assess the relationship between umbilical cord insertion site and vasa previa.
Main Methods:
- Prospective examination of umbilical cord insertion sites via ultrasound.
- Study conducted in 3647 cases during the first trimester (2006-2011).
- Correlation of first-trimester findings with delivery outcomes.
Main Results:
- Vasa previa was diagnosed in 10 cases, with an incidence of 1:365.
- All diagnosed cases of vasa previa at delivery were identified as having a lower cord insertion in the first trimester.
- No misdiagnosed cases were reported.
Conclusions:
- Ultrasonographic evaluation suggests vasa previa is more frequent than commonly believed.
- Early identification of umbilical cord abnormalities, including lower cord insertion, is recommended.
- Systematic screening in early gestation can aid in diagnosing vasa previa.
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