Value of yolk sac size using trans-vaginal

Original article


Suliman M Eldurrija and Ibrahim A Larbah

Misurata Central Hospital, Misurata, Libya

JMJ Vol.4 No. 2 (Autumn) 2005: 114-118


The yolk sac is small and to date largely ignored structure, has a vital and interesting part to play in human embryonic development. This study is a prospective for three years duration ( from September 1999 till September 2002 ), 366 patients were scanned in the first trimester , in different gestational ages utilizing trans – vaginal sonography. 1080 yolk sac diameters were collected, each yolk sac was followed until either an ongoing pregnancy or abortion was documented after the of first trimester. At the end of first trimester, the study group was divided into two subgroups. sub-group A – represented those who had a successful first trimester ( 294 patients ), and subgroup B included patients in which pregnancy ended by abortion (72 patients). The growth pattern of normal yolk sac diameter has constructed, one case of subgroup A was found outside 2 standard deviation which did not persist for more than one week, mean while (87.5%) of abnormal cases were outside 2 S.D. and associated with abnormal outcome, data analysis showed statistical significance. The study was concluded that any yolk sac diameter larger than 2 S.D of the mean is considered as abnormal ultrasonic findings and always carries a poor prognostic outcome.

Keywords: Yolk sac, Trans-vaginal sonography