In cases of a positive HCG urine test without an IUP identified a differential diagnosis to consider is ectopic pregnancy.

Most cases referred to as possible ectopic pregnancies are actually early intrauterine pregnancies. An enlarged uterus with a thick endometrial lining and no evidence of an IUP is typical of ectopic pregnancy. Generally, most of the following findings would be accompanied with clinical signs of ectopic:

  
     
 

  • Fluid in the posterior cul-de-sac with internal echoes which indicates leakage or rupture (If patient presents with pain of 6 or greater on a 1-10 scale, do not perform ultrasound. Refer patient to the Emegency Room.)

  • A mass in the adnexa

  • An adnexal ring sign, (donut-like ring which has a gestational sac-like appearance in the adnexa

  • An extrauterine embryo with heart motion

  • Pseudo sac seen in uterus (Fluid filled area in uterus, usually with irregular borders)

  
     
 
 



In the first trimester of pregnancy the standard of care for ultrasound includes transvaginal scanning. It is especially essential when an IUP is not identified transabdominally. If a thickened endometrium is indentified and an IUP is not visualized the differential diagnosis should include consideration of ectopic pregnancy.

 
 
     
 
 
 



If ectopic pregnancy is suspected, the protocol should include a thorough scan of the right and left adnexas to rule out an adnexal mass, adnexal ring sign or an extrauterine embryo with heart motion. Imaging of the posterior cul-de-sac should be included to rule-out leakage or rupture of the fallopian tube. Patient is referred for follow-up ASAP for further evaluation.