Am Fam Physician. 2006 Jun 1;73(11):1892.
to the editor: In the article “Diagnosis and Management of Ectopic Pregnancy”1 in the November 1, 2005, issue of American Family Physician, Drs. Lozeau and Potter suggest that serum progesterone levels detect pregnancy failure, are insensitive in diagnosing ectopic pregnancy, and that algorithms incorporating progesterone levels miss more ectopic pregnancies and require more surgeries. Although we agree that there is no specific cutoff for progesterone levels that accurately diagnose ectopic pregnancy,2 progesterone levels may still play a useful role in the evaluation and management of suspected ectopic pregnancy.
Progesterone levels may be helpful in the evaluation of suspected ectopic pregnancy if they are very high or very low. The authors quote a sensitivity of 15 percent for progesterone levels in ectopic pregnancy. Of course, the sensitivity of a quantitative test depends on the specific level selected for the cutoff, but in a meta-analysis2 of 27 studies, sensitivities ranged from 44 to 100 percent, depending on the threshold. In 12 studies with a total of 1,107 women, only 2.6 percent of women with an ectopic pregnancy had progesterone levels greater than 20 ng per mL (64 nmol per L).2 In 13 studies, only five of 1,615 women (0.3 percent) with progesterone levels less than 5 ng per mL (15.9 nmol per L) had a viable intrauterine pregnancy.2 By establishing the low likelihood of interrupting a viable intrauterine pregnancy, serum progesterone measurements may allow for the option of a dilatation and curettage to rule out an ectopic pregnancy in women with an indeterminate ultrasound examination.3 None of the studies cited by Drs. Lozeau and Potter1 incorporated progesterone measurements into a diagnostic algorithm in this way.
Serum progesterone measurements also may have a prognostic use. In women with a progesterone level below 10 ng per mL (31.8 nmol per L) and a human chorionic gonadotropin (hCG) level below 1,500 mIU per L (1,500 IU per mL), spontaneous resolution of ectopic pregnancy is more likely.4 Progesterone levels have been included in a scoring instrument designed to predict the success of expectant or medical management of ectopic pregnancy.5 In addition, serum progesterone levels fell to normal (less than 1.5 ng per mL [4.8 nmol per L]) faster than hCG levels following treatment with methotrexate or laparoscopic salpingostomy and for this reason may be a better marker for predicting successful treatment.6
REFERENCESshow all references
1. Lozeau A, Potter B. Diagnosis and management of ectopic pregnancy. Am Fam Physician. 2005;72:1707–14....
2. Mol B, Lijmer JG, Ankum WM, van der Veen F, Bossuyt PM. The accuracy of single serum progesterone measurement in the diagnosis of ectopic pregnancy: a meta-analysis. Hum Reprod. 1998;13:3220–7.
3. Carson SA, Buster JE. Ectopic pregnancy. N Engl J Med. 1993;329:1174–81.
4. Elson J, Tailor A, Banerjee S, Salim R, Hillaby K, Jurkovic D. Expectant management of tubal ectopic pregnancy: prediction of successful outcome using decision tree analysis. Ultrasound Obstet Gynecol. 2004;23:552–6.
5. Fernandez H, Lelaidier C, Thouvenez V, Frydman R. The use of a pretherapeutic, predictive score to determine inclusion criteria for the non-surgical treatment of ectopic pregnancy. Hum Reprod. 1991;6:995–8.
6. Saraj AJ, Wilcox JG, Najmabadi S, Stein SM, Johnson MB, Paulson RJ. Resolution of hormonal markers of ectopic gestation: a randomized trial comparing single-dose intramuscular methotrexate with salpingostomy. Obstet Gynecol. 1998;92:989–94.
Send letters to Kenneth W. Lin, MD, MPH, Associate Deputy Editor for AFP Online, e-mail: email@example.com, or 11400 Tomahawk Creek Pkwy., Leawood, KS 66211-2680.
Please include your complete address, e-mail address, and telephone number. Letters should be fewer than 400 words and limited to six references, one table or figure, and three authors.
Letters submitted for publication in AFP must not be submitted to any other publication. Possible conflicts of interest must be disclosed at time of submission. Submission of a letter will be construed as granting the American Academy of Family Physicians permission to publish the letter in any of its publications in any form. The editors may edit letters to meet style and space requirements.
Copyright © 2006 by the American Academy of Family Physicians.
This content is owned by the AAFP. A person viewing it online may make one printout of the material and may use that printout only for his or her personal, non-commercial reference. This material may not otherwise be downloaded, copied, printed, stored, transmitted or reproduced in any medium, whether now known or later invented, except as authorized in writing by the AAFP. Contact firstname.lastname@example.org for copyright questions and/or permission requests.
Want to use this article elsewhere? Get Permissions