What term describes a centrally located endometrial fluid collection demonstrated with a coexisting ectopic pregnancy?

• A. Pseudogestational pregnancy
• B. True gestational sac
• C. Endometritis
• D. Molar pregnancy

Answer: (A)

A pseudogestational sac is the term that describes a centrally located fluid collection within the endometrium seen when an ectopic pregnancy coexists. This fluid collection can mimic a real intrauterine gestational sac on ultrasound, which can lead to confusion if there’s also an ectopic pregnancy. The giveaway feature is that there is no fetal pole or yolk sac inside the collection, and it typically lacks the double decidual sac sign and the vascularity you’d expect with a true intrauterine pregnancy. In contrast, a true gestational sac would contain a developing embryo and/or yolk sac and would show the characteristic signs of an intrauterine pregnancy, or it would be absent of such signs if there were no intrauterine pregnancy. Endometritis refers to uterine infection and doesn’t present as a sac-like fluid collection, and a molar pregnancy involves abnormal placental tissue with a distinct diffuse pattern, not a single endometrial fluid sac.