Hum. Reprod. Advance Access originally published online on July 25, 2007
Human Reproduction 2007 22(10):2589-2593; doi:10.1093/humrep/dem207
Mid-cycle serum levels of endogenous LH are not associated with the likelihood of pregnancy in artificial frozen-thawed embryo transfer cycles without pituitary suppression
1 Department of Obstetrics and Gynecology, University Clinic of Schleswig-Holstein, Campus Luebeck, Ratzeburger Allee 160, 23538 Luebeck, Germany 2 Unit for Human Reproduction, 1st Department of Obstetrics and Gynecology, Aristotle University of Thessaloniki, Greece
3 Correspondence address. Tel: +49 451 500 2134; Fax: +49 451 500 2170; E-mail: georg.griesinger{at}frauenklinik.uni-luebeck.de
BACKGROUND: The aim of the present study was to evaluate the association between clinical pregnancy and serum luteinizing hormone (LH) levels, assessed after 14 days of endometrial preparation with estradiol (E2) in the absence of pituitary suppression during a frozen-thawed embryo transfer (FRET) cycle.
METHODS: A total of 513 patients undergoing their first FRET cycle (01/99 to 11/05) participated in this prospective study. Endometrium preparation for FRET was started on cycle day 1 and continued for a fixed period of 14 days with trans-dermal E2 patches. On day 14, serum LH, progesterone and E2 levels were assessed. On day 15, progesterone supplementation was initiated and patients underwent embryo transfer on day 17 or day 18. The association between clinical pregnancy and LH levels was evaluated in groups of patients defined according to Tukey's Hinges percentile analysis of LH levels on day 14. In addition, robust logistic regression was performed with the dependent variable clinical pregnancy and independent variables LH, progesterone, embryos score, cycle rank and gravidity.
RESULTS: Age, BMI, parity, cycle rank, embryo number, embryo score, endometrial diameter, E2 and progesterone were not significantly different in cycles with low (0.1–8.1 IU/l; n = 132), intermediate (8.2–19.4 IU/l; n = 238) and high (20.0–78.0 IU/l; n = 143) levels of LH, respectively. Clinical pregnancy rates were not significantly different in cycles with low [12.1%, 95% confidence intervel (CI) 7.6–18.8], intermediate (13.4%, 9.7—18.4) and high levels of LH (16.1%, 11.0–23.0). Robust logistic regression analysis indicated that embryo score [Odds ratios (OR) 1.04, 95% CI 1.02–1.06, P < 0.01] was statistically significantly associated with the likelihood of clinical pregnancy achievement, but not day 14 levels of LH or progesterone, gravidity or cycle rank.
CONCLUSIONS: The likelihood of clinical pregnancy is not associated with serum LH levels on day 14 of an artificial FRET cycle. Hormonal monitoring of LH levels does not yield useful information with regard to cycle management and patient prognosis, and should therefore not be conducted.
Key words: frozen-thawed embryo transfer/luteinizing hormone/progesterone/clinical pregnancy
Submitted on April 11, 2007; resubmitted on June 4, 2007; accepted on June 13, 2007.