Ultrasound diagnosis

Transvaginal ultrasound is the standard test now for the diagnosis of ectopic pregnancy.

Tubal ectopic viable anonomous
3D rendered view of a large tubal ectopic pregnancy containing a yolk sac and embryo visualised using vaginal ultrasonography
Interstitial 3D anon
3D coronal view of a uterus with a left sided interstitial ectopic pregnancy

Most scans undertaken for a gynaecological indication are carried out transvaginally, using high frequency ultrasound, so that the ultrasound transducer on the end of a vaginal probe is closer to the area of interest and provides much better image resolution. To put this in context, it is possible to see the heartbeat of an embryo approximately 2 weeks earlier vaginally than abdominally. Similarly, all the studies on classifying the lining of the womb or ovarian cysts have been based on high resolution vaginal ultrasound, and so using abdominal scanning when looking at possible gynaecological problems is not the best thing to do and may well give quite different results.

Carrying out a vaginal ultrasound scan is also a dynamic process and allows the examiner to look at the mobility and tenderness of the organs in the pelvis – both of which are factors when considering a possible diagnosis.

Over 70% of ectopic pregnancies are seen on ultrasound on the first scan and well over 90% before surgery.

Download leaflet: Pregnancy of Unknown Location (PDF)


Testa AC, Van Holsbeke C, Mascilini F, Timmerman D. Dynamic and interactive gynaecological ultrasound examination. Ultrasound in Obstetrics and Gynaecology 2009 Aug; 34(2):225-9. doi: 10.1002/uog.

Kirk E, Papageorghiou AT, Condous G, Tan L, Bora S, Bourne T. The diagnostic effectiveness of an initial transvaginal scan in detecting ectopic pregnancy. Human Reproduction 2007 Nov; 22(11):2824-2828.

Condous G, Okaro E, Khalid A, Lu C, Van Huffel S, Timmerman D, Bourne T. The accuracy of transvaginal ultrasonography for the diagnosis of ectopic pregnancy prior to surgery. Human Reproduction 2005 May; 20(5):1404-1409.

If you need any support or advice regarding the diagnosis or treatment of an ectopic pregnancy please email us at ept@ectopic.org.uk or call 020 7096 1838 and we will put you in touch with clinical specialists who would be happy to offer a point of view.