Relation between types of yolk sac abnormalities and early embryonic morphology in first‐trimester missed miscarriage

Abstract

This study found a significant relation between YS abnormalities and embryonic morphology in missed miscarriage cases. This was most evident with abnormalities in YS diameter rather than the YS shape or appearance. The commonest combinations met in our cases were growth disorganized 1 embryos with an absent YS, normal embryonic morphology with normal or small YS, and isolated embryonic defects with cystic YS.

A Yolk Sac Larger Than 5 mm Suggests an Abnormal Fetal Karyotype, Whereas an Absent Embryo Indicates a Normal Fetal Karyotype

“…Ethics approval was obtained from the Ethics Committee of our hospital (No. [24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42].…”

Sonographic Evaluation of the Yolk Sac and its Relationship to the Pregnancy Outcome

“…These findings indicate that the existence of an enlarged yolk sac (with a diameter of >_5mm) is of evident clinical significance when it is specified before the 7 th week of gestation [2].In 2015, Shetty et al, also reported that a yolk sac greater than 5mm (large yolk sac) between 6-7.5 weeks gestation was a good indicator and that it would end in abortions [13] . In 2016, Ashoush et al, a large yolk sac was most commonly detected (in 36.8%) with isolated congenital anomalies (representing 63.6% of all cases with too-large yolk sac) [1] . In 2016, Srivastava et al, also reported that an enlarged yolk sac was responsible for 77.78% of the abortions [14] .…”

“…An absent yolk sac was associated with missed abortion in all cases of this study. In 2016, Ashoush Sh, et al, reported that the majority of their embryos with absent YS were GD1 (Growth disorganized (GD) 1, corresponding with the absent embryo (blighted ovum) [1].Although there is no clear agreement, an enlarged yolk sac can be depicted as a yolk sac with a diameter of 5 or 6mm. Generally, it has been suggested that an abnormally large yolk sac indicates poor obstetric outcome [11] .…”

“…Generally, it has been suggested that an abnormally large yolk sac indicates poor obstetric outcome [11] . A recent study has shown that a yolk sac diameter of greater than 6mm is associated with an increased risk of spontaneous abortion [1] . However, a few authors have mentioned the existence of a very large yolk sac (with a diameter of 8.1mm) in normal live pregnancy [12] .…”

“…THE yolk sac is the first anatomical structure identified ultrasonographically within the Gestational sac. It is usually identifiable as a round structure, made up of an anechoic center, and bordered by an echogenic, round, regular and welldefined rim [1] .…”