Screening for ectopic pregnancy

Last reviewed: January 29, 2021

Recommendation:

• Diagnosis of an ectopic pregnancy should be excluded in women who have a concerning history or examination.

Strength of recommendation: Strong

Quality of evidence: Low

Epidemiology

Data are scant from low resource settings regarding rates of ectopic pregnancy; in the United States and United Kingdom, reported rates range from 1-2% of pregnancies (Stulberg, Cain, Dahlquist, & Lauderdale, 2013; Tao, Patel, & Hoover, 2016; Trabert, Holt, Yu, Van den Eeden, & Scholes, 2011; Webster, Eadon, Fishburn, & Kumar, 2019). Ectopic pregnancy accounts for 2.7% of pregnancy-related deaths in the United States (Creanga, Syverson, Seed, & Callaghan, 2017). Ectopic pregnancy accounts for approximately 1% of pregnancy-related deaths in low resource settings where other causes of maternal death are more prevalent (Khan, Wojdyla, Say, Gulmezoglu, & Van Look, 2006).

Risk factors

Factors with the highest associated risk of ectopic pregnancy in pregnant women are:

Other risk factors include a history of infertility and assisted reproductive technology, a history of pelvic infections, multiple partners, early age at first intercourse, early age at first oral contraceptive use and smoking (ACOG, 2018; Ankum et al., 1996; Barnhart, 2009, Gaskins et al., 2018; Olamijulo et al., 2020).

Screening

Half of all ectopic pregnancies occur in women with no risk factors and with a benign clinical presentation in high-income countries (Stovall, Kellerman, Ling, & Buster, 1990), whereas in low- and middle-income countries, women are more likely to present with acute clinical features, including hemodynamic instability (Olamijulo et al., 2020). Providers should screen women for ectopic pregnancy risk factors during the history and physical examination including relevant history, such as previous ectopic pregnancy, tubal ligation, tubal surgery or an IUD in place. Screening should also include symptoms and signs of ectopic pregnancy found during history taking and physical examination, such as an adnexal mass, pain on examination or vaginal bleeding.

Some women present for abortion care very early in pregnancy, before there is definitive ultrasound evidence of an intrauterine gestation. A 2020 systematic review, including three retrospective comparative cohort studies of 5,315 women seeking early medical or aspiration abortion, found that there was no increase in incidence of missed diagnosis of ectopic pregnancy or incomplete abortion when abortion was initiated prior to ultrasound evidence of intrauterine pregnancy in women who did not have signs or symptoms of an ectopic pregnancy (Schmidt-Hansen, Cameron, Lord, & Hasler, 2020).

Treatment for high-risk women

Ultrasound and serial hCG testing are often used to help assess pregnancy location (Fields & Hathaway, 2017). In some cases, the most expeditious way to confirm an intrauterine pregnancy is to perform vacuum aspiration; presence of products of conception in the uterine aspirate confirms that it was intrauterine. A woman with suspicious signs and symptoms or a concerning physical exam should be diagnosed and treated as soon as possible or transferred immediately to a facility that can manage ectopic pregnancy. Early diagnosis and treatment of ectopic pregnancy can help preserve fertility and save women’s lives.

Post-procedure screening

For women undergoing vacuum aspiration, the aspirate should be strained and examined to confirm the presence of products of conception (see “Vacuum aspiration: Examining products of conception”). If products of conception are not seen, a diagnosis of ectopic pregnancy should be considered.

References

American College of Obstetricians and Gynecologists. (2018). Practice bulletin No 193: Tubal ectopic pregnancy. Obstetrics & Gynecology 131, e91-e103.

Ankum, W. M., Mol, B. W. J., Van der Veen, F., & Bossuyt, P. M. M. (1996). Risk factors for ectopic pregnancy: A meta-analysis. Fertility and Sterility, 60(6), 1093-9.

Barnhart, K. T. (2009). Clinical practice. Ectopic pregnancy. New England Journal of Medicine, 361(4), 379-387.

Creanga, A. A., Syverson, C., Seed, K., & Callaghan, W. M. (2017). Pregnancy-related mortality in the United States, 2011-2013. Obstetrics & Gynecology, 130(2), 366-373.

Fields, L., & Hathaway, A. (2017). Key concepts in pregnancy of unknown location: Identifying ectopic pregnancy and providing patient-centered care. Journal of Midwifery and Womens Health, 62(2), 172-179.

Gaskins, A. J., Missmer, S. A., Rich-Edwards, J. W., Williams, P. L., Souter, I., & Chavarro, J. E. (2018). Demographic, lifestyle, and reproductive risk factors for ectopic pregnancy. Fertility and Sterility, 110(7), 1328-1337.

Jacob, L., Kalder, M., & Kostev, K. (2017). Risk factors for ectopic pregnancy in Germany: a retrospective study of 100,197 patients. German Medical Science, 15, Doc19.

Khan, K. S., Wojdyla, D., Say, L., Gulmezoglu, A. M., & Van Look, P. F. (2006). WHO analysis of causes of maternal death: A systematic review. The Lancet, 367(9516), 1066-1074.

Olamijulo, J.A., Okusanya, B.O., Adenekan, M.A., Ugwu, A.O., Olorunfemi, G., & Okojie, O. (2020). Ectopic pregnancy at the Lagos University Teaching Hospital, Lagos, South-Western Nigeria: Temporal trends, clinical presentation and management outcomes from 2005 to 2014. Nigerian Postgraduate Medical Journal, 27, 177-83.

Schmidt-Hansen, M., Cameron, S., Lord, J., & Hasler, E. (2020). Initiation of abortion before there is definitive ultrasound evidence of intrauterine pregnancy: A systematic review with meta-analyses. Acta Obstetricia et Gynecologica Scandinavica 99, 451-458.

Stovall, T. G., Kellerman, A. L., Ling, F. W., & Buster, J. E. (1990). Emergency department diagnosis of ectopic pregnancy. Annals of Emergency Medicine, 19(10), 1098-1103.

Stulberg, D., Cain, L. R., Dahlquist, I., & Lauderdale, D. S. (2013). Ectopic pregnancy rates in the Medicaid population. American Journal of Obstetrics & Gynecology, 208(4), 274.e1-7.

Tao, G., Patel, C., & Hoover, K. W. (2016). Updated estimates of ectopic pregnancy among commercially and Medicaid-insured women in the United States, 2002-2013. Southern Medical Journal, 110(1), 18-24.

Trabert, B., Holt, V. L., Yu, O., Ven Den Eeden, S. K., & Scholes, D. (2011). Population-based ectopic trends, 1993-2007. American Journal of Preventative Medicine, 40(5), 556-560.

Webster, K., Eadon, H., Fishburn, S, & Kumar, G. (2019). Ectopic pregnancy and miscarriage: diagnosis and initial management: summary f updated NICE guidance. British Medical Journal, 367, 16283.