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Updated: Jul 11, 2026

In Vitro Imaging and Quantification of the Drug Targeting Efficiency of Fluorescently Labeled GnRH Analogues
Published on: March 21, 2017
High-dose recombinant LH add-back strategy using high-dose GnRH antagonist is an innovative protocol compared with
J A Garcia-Velasco1, H J T Coelingh Bennink, R Epifanio
1Instituto Valenciano de Infertilidad Madrid, Madrid, Spain.
Abstract:
High daily doses of gonadotrophin-releasing hormone (GnRH) antagonists during the follicular phase of ovarian stimulation were associated with low implantation rates. To test if this occurred because of profound pituitary suppression, the pituitary response was suppressed with a high-dose GnRH antagonist and recombinant LH (rLH) was added back to correct the implantation rate. An open-label, randomized, controlled, prospective clinical study in 60 patients undergoing IVF was performed. GnRH antagonist was initiated on day 6 of stimulation (2 mg/day) together with 375 IU rLH, and maintained until the day of HCG administration. Controls received 0.25 mg/day GnRH antagonist. Fluctuating LH concentrations were present on days 3 and 6 in both groups. This strong fluctuation continued on day 8 and on the day of HCG administration in the control (low-dose) group, where 30% of patients had LH concentrations <1 IU/l on the HCG day. The study (high-dose) group showed stable LH concentrations on day 8 and on the HCG day, with no LH surges. No clinical differences were found between groups. The LH add-back strategy (375 IU/day) rescued the adverse effects that high doses of GnRH imposed on implantation. These results suggest that rLH should be considered during ovarian stimulation with GnRH antagonist.
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