A G1P0 10-week pregnant female presents to the ED with lower abdominal pain and vaginal spotting. She’s had no prenatal care. Being the highly motivated resident that you are, before even the urine is collected and the pregnancy is verified, you bring the ultrasound machine bedside and see this:

Ectopic_01_zoom2

What’s the diagnosis?

Answer: Ectopic pregnancy

Ectopic_01_zoom3

The first image was zoomed in on the fetus and therefore the ovary adjacent to it was not visualized. What may be mistaken for an IUP is actually an ectopic pregnancy. Do not let this happen to you. To quote Bret Nelson who quoted Reuben Strayer, “P does not equal IUP”.

Tips for avoiding pitfalls for missing ectopics:

1) Always obtain the transabdominal view before transvaginal even if you think it’s too early in the pregnancy to see anything. This gives you a sense of the landscape of the anatomy.
2) Have the patient empty her bladder before using the transvaginal probe.
3) The myometrium should be at least 8mm thick and should surround the gestational sac. If this is in question, have a high suspicion that the fetus is not in the uterus.
4) Fan through the entire uterus and demonstrate the endometrial stripe and look at the cul-de-sac for free fluid.
5) Obtain two views for both transabdominal and transvaginal.

Sinai EM US website’s tutorial:
http://sinaiem.us/tutorials/pelvis