An anembryonic pregnancy , also known as egg huero , is that where the embryo only develops the embryonic sac . It is characterized by a gestational sac of normal appearance, but with absence of embryo. The most common is that it occurs after the death of the embryo that is accompanied by the development of the trophoblast . It is one of the causes ofspontaneous abortion .
For its diagnosis , the size must be sufficient to be evaluated with ultrasound . The criteria depends on the type of ultrasound examination performed. A pregnancy is anembryonic if a vaginal ultrasound reveals an average sac diameter (DMS) greater than 25 mm without yolk sac, or a DMS greater than 25 mm without embryo. A transabdominal image without transvaginal imaging may be sufficient for the diagnosis of early pregnancy failure when an embryo whose skull-caudal length is 15 mm or more has no visible cardiac activity. 1
- Back to top↑ Doubilet PM, Benson CB, Bourne T, Blaivas M; Society of Radiologists in Ultrasound Multispecialty Panel on Early Trimester Diagnosis of Miscarriage and Exclusion of Viable Intrauterine Pregnancy, Barnhart KT, Benacerraf BR, Brown DL, Filly RA, Fox JC, Goldstein SR, Kendall JL, Lyons EA, Porter MB, Pretorius DH, Timor-Tritsch IE (2013 Oct 10). ‘Diagnostic criteria for nonviable early pregnancy in the first trimester’ . N Engl J Med 369 (15): 1443-51. doi : 10.1056 / NEJMra1302417 . PMID 24106937 .