Ectopic pregnancy diagnosis and the pseudo-sac

Fertil Steril. 2004 May;81(5):1225-8. doi: 10.1016/j.fertnstert.2003.09.068.


Objective: To evaluate the impact of an ultrasound finding of a pseudo-sac (PS), a uterine sac without a double decidual ring or a yolk sac, on the management of cases with possible ectopic pregnancy.

Design: A retrospective review of a series of cases.

Setting: A general hospital.

Patient(s): Seventy-seven patients who had a diagnostic laparoscopy over a period of 3 years for suspected ectopic pregnancy.

Main outcome measure(s): A logistic regression analysis was conducted to evaluate the effect of the ultrasound finding of a PS on predicting a negative finding at laparoscopy.

Result(s): The report of a PS is significantly associated with a false-positive diagnosis of ectopic pregnancy.

Conclusion(s): A diagnosis of PS should not be interpreted as indicative of an ectopic pregnancy because radiological differentiation between an early intrauterine pregnancy failure and an ectopic pregnancy is not possible.

MeSH terms

  • False Positive Reactions
  • Female
  • Hexachlorocyclohexane / blood
  • Humans
  • Logistic Models
  • Pregnancy
  • Pregnancy, Ectopic / diagnosis*
  • Retrospective Studies
  • Ultrasonography
  • Uterus / diagnostic imaging*


  • Hexachlorocyclohexane
  • beta-hexachlorocyclohexane