Related Experiment Video
Updated: Jul 29, 2026

Fertility Preservation Through Oocyte Vitrification: Clinical and Laboratory Perspectives
Published on: September 16, 2021
Ovarian sensitivity to gonadotrophins in patients with PCO is unaffected by suppression of LH
R Fleming1, M P Hamilton, C Conaghan
1Department of Obstetrics and Gynaecology, University of Glasgow, UK.
Abstract:
Infertile women with oligomenorrhoea and elevated LH concentrations (presumed polycystic ovary disease, PCO) were treated with exogenous gonadotrophins, HMG and HCG, for induction of follicular growth and ovulation, respectively. This was effected in the absence or presence of a gonadotrophin releasing hormone analogue (GnRH-A) to suppress basal LH and the positive feedback surge of LH. Analyses of the duration of HMG therapy required to attain the degree of stimulation for HCG to be administered showed no difference between those with and without LH suppression. Analyses of the ultrasound estimations of rates of follicle growth and continued recruitment during the course of HMG also failed to show any effect of LH suppression. These data show that the high sensitivity of these patients to HMG is not related to the circulating LH concentrations.
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