A single midcycle dose of levonorgestrel similar to emergency contraceptive does not alter the expression of the L-selectin ligand or molecular markers of endometrial receptivity.
Author(s): Palomino WA, Kohen P, Devoto L
Affiliation(s): Instituto de Investigaciones Materno Infantil, Universidad de Chile, Santiago de Chile, Chile. firstname.lastname@example.org
Publication date & source: 2010-10, Fertil Steril., 94(5):1589-94. Epub 2009 Nov 11.
Publication type: Randomized Controlled Trial; Research Support, Non-U.S. Gov't
OBJECTIVE: To examine the effects of a single-dose of 1.5 mg of levonorgestrel (commonly used as emergency contraceptive) on endometrial receptivity biomarkers through the oral or vaginal route. DESIGN: Prospective randomized single-blinded trial. SETTING: Affiliated Hospital and University Research Center. PATIENT(S): Fertile normal women previously sterilized by tubal ligation. INTERVENTION(S): Levonorgestrel (1.5 mg) was administered on the day of LH surge either orally (n = 14) or vaginally (n = 13). MAIN OUTCOME MEASURE(S): Molecular assessment of endometrial progesterone receptors, L-selectin ligand, glicodelin-A and alphavbeta3 integrin by Immunohistochemistry and reverse transcriptase-polymerase chain reaction. RESULT(S): Plasma progesterone concentration and endometrial dating were not different. The pattern of progesterone receptors and glycodelin-A expression was not affected during the early and midsecretory phase. Some endometrial biopsies from the group in which levonorgetrel was orally administered showed areas of glandular atrophy and stromal decidualization. However, the expression of the progesterone receptor, L-selectin ligand, alphavbeta3 integrin, and glycodelin-A were not different between the groups. CONCLUSION(S): Levonorgestrel, given as emergency contraceptive on the day of LH surge, does not disrupt either ovulation or progesterone production by the corpus luteum. The contraceptive mechanism of levonorgestrel at the time of LH surge does not include changes in the progesterone receptors or the endometrial receptivity biomarkers. Copyright (c) 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.