pseudogestational sac seen in:

In an ectopic pregnancy,a pseudosac or an empty sac without yolk sac is formed by decidual thickening and therefore is central in location. Refer page no 303 of Shaw's textbook of gynaecology,16 th edition. True Gestational Sac (GS) : is eccentric in position within the endometrium of fundus or body of the uterus. Double decidua sign of the gestational sac is due to the interface between the decidua and the chorion which appears as two distinct layers of the wall of the gestation sac. Presence of yolk sac or fetal pole within the gestation sac confirms pregnancy. True gestational sac size increases 1 mm/ day. Pseudogestational sac or pseudosac : is irregular in outline, usually centrally located in the uterus, has no double decidua sign and the sac remains empty. Reference: Dutta's Textbook of Obstetrics 7th edition page no 646