Defining "abnormal rise" is the elephant in the room.
Kadar and colleagues originally suggested that 85% of viable intrauterine pregnancies (IUPs) will have a rise in hCG levels of at least 66% every 48 hours, leading to what is commonly called the "doubling rule." (7) Barnhart and colleagues showed that the slowest recorded hCG rise for a viable pregnancy in 48 hours was 53%, demonstrating that the hCG level does not double in 48 to 72 hours as traditionally expected. (8) In their final model, the authors calculated that 99% percent of normal IUPs should have an increase of at least 53% in 2 days, moving the bar for a "normal" hCG rise even lower. This also implies that 1% of viable IUPs may have a rise of less than 53% over 2 days. I have to wonder how many viable, wanted pregnancies have been interrupted by the misguided use of discriminatory zones or abnormal rises resulting in the emptying of the pregnant uterus?
Clinical assessment and ultrasonography should continue to be the mainstay of management of ectopic pregnancy. When surgical diagnosis is needed, laparoscopy should be considered. In this day and age, when we are being more cautious about emptying a uterus based on ultrasound measurements of the fetus or gestational sac, why are we still so eager to base that decision on laboratory values? Are we really willing to accept that 1% of the time we will be terminating a viable pregnancy? We should stop the continued propagation of flow charts and strategies that use hCG discriminatory zones or abnormal rises to determine viability and when to evacuate the uterus. A contemporary update to address the issue is needed.
Devin Namaky, MD
(1.) Seeber B, Barnhart K. Suspected ectopic pregnancy. Obstet Gynecol. 2006;107(2):399-413.
(2.) Mukul LV, Teal SB. Current management of ectopic pregnancy. Obstet Gynecol Clin North Am. 2007;34(3):403-419.
(3.) Ectopic pregnancy. In: Hoffman BL, Schorge JP, Schaffer JI, et al, eds. Williams Gynecology. 2nd ed. New York, NY: McGraw-Hill Professional; 2012:198-218.
(4.) Lobo RA. Ectopic pregnancy. In: Lentz GM, ed. Comprehensive Gynecology. 6th ed. Philadelphia, PA: Elsevier Mosby; 2012:361-382.
(5.) Damario MA, Rock IA. Ectopic pregnancy. In: Rock JA, Iones HW III, eds. Te Linde's Operative Gynecology. 10 th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2008:798-824.
(6.) Tulandi T. Ectopic pregnancy: clinical manifestations and diagnosis. UpToDate Web site. http://www.uptodate.com/contents/ectopic-pregnancy-clinical-manifestations-and-diagnosis. Updated October 22, 2014. Accessed February 18, 2015.
(7.) Kadar N, Caldwell BV, Romera R. A method of screening for ectopic pregnancy and its indications. Obstet Gynecol. 1981;58(2):162-166.
(8.) Barnhart KT, Sammel MD, Rinaudo PF, Zhou L, Hummel AC, Guo W. Symptomatic patients with an early viable intrauterine pregnancy: hCG curves redefined. Obstet Gynecol. 2004; 104(1):50-55.
"STOP USING THE HCG DISCRIMINATORY ZONE OF 1,500 TO 2,000 mIU/mL TO GUIDE INTERVENTION DURING EARLY PREGNANCY"
ROBERT L. BARBIERI, MD (EDITORIAL; JANUARY 2015)
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|Title Annotation:||Comment & Controversy|
|Article Type:||Letter to the editor|
|Date:||Mar 1, 2015|
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