to the editor: I would like some clarification on a discrepancy I found between two articles in American Family Physician (AFP), “Management of Spontaneous Abortion”¹ in the October 1, 2005, issue and “Diagnosis and Management of Ectopic Pregnancy”² in the November 1, 2005, issue.

The authors of the article on spontaneous abortion¹ use the Advanced Life Support in Obstetrics syllabus³ to substantiate the statement that, “When transvaginal ultrasonography reveals an empty uterus and the quantitative serum hCG [human chorionic gonadotropin] level is greater than 1,800 mIU per mL (1,800 IU per L), an ectopic pregnancy should be considered.”¹

However, the article on ectopic pregnancy² refers to a previous AFP article⁴ on ectopic pregnancy to support the statement that, “ectopic pregnancy is suspected…if transvaginal ultrasonography does not show an intrauterine gestational sac and the patient’s beta-hCG level is 1,500 mIU per mL (1,500 IU per L) or greater.”²

Thank you for any clarification you can provide on the current standard for this critical management issue.

in reply:We appreciate the opportunity to clarify the issue regarding the beta-human chorionic gonadotropin (beta-hCG) level above which a gestational sac can be visualized consistently with transvaginal ultrasound. The beta-hCG level at which we can visualize a gestational sac has decreased over time with advances in ultrasound technology. The article by the Advanced Life Support in Obstetrics (ALSO) syllabus refers to an article published in 1986.¹ The recent literature regarding evaluation for possible ectopic pregnancy is consistent in recommending that, at a beta-hCG level of 1,500 mIU per mL (1,500 IU per L) or greater, the gestational sac should be visualized with transvaginal ultrasound.^2–6 Our diagnostic strategy reflects this recommendation.