Intradecidual sac sign
Citation, DOI, disclosures and article data
At the time the article was created Frank Gaillard had no recorded disclosures.View Frank Gaillard's current disclosures
At the time the article was last revised Jeremy Jones had no recorded disclosures.View Jeremy Jones's current disclosures
Intradecidual sac sign (IDSS) is a useful feature in identifying an early intrauterine pregnancy (IUP) as early as 25 days of gestation1. The threshold level (earliest one can see the sign) is 24 days of gestation and the discriminatory level (one should always see the sac) is 47 days. As per this sign, site of implantation is seen as an early gestational sac or an intrauterine fluid collection or an echogenic area in a markedly thickened decidua on one side of the uterine cavity. This can be better identified by identifying the collapsed uterine cavity.
Although useful if seen, its presence has been reported in fewer cases of IUP than originally thought (~60%), and its absence does not exclude an IUP.
History and etymology
It was first described by Yeh et al. in 1986.