EFFECT OF HIGH DOSE EXOGENOUS OESTROGEN ON MIDCYCLE LUTEINIZING HORMONE SURGE IN HUMAN SPONTANEOUS CYCLES
- 1 October 1987
- journal article
- research article
- Published by Wiley in Clinical Endocrinology
- Vol. 27 (4), 453-459
- https://doi.org/10.1111/j.1365-2265.1987.tb01173.x
Abstract
Induction of multiple follicular development in women results in supraphysiological serum oestradiol (E2) levels and marked reduction of the endogenous LH surge. To examine whether high serum E2 levels at midcycle can suppress gonadotrophin secretion during the LH surge, five normally ovulating women were given an intramuscular injection of 10 mg oestradiol benzoate 6-42 h before the expected endogenous LH surge. The results were compared with the preceding untreated control cycle. Serum E2 levels at the onset of the LH surge (mean .+-. SEM) were significantly higher in the oestrogen-treated cycles (13,600 .+-. 1963 pmol/l) than in the control cycles (1012 .+-. 116 pmol/l)(P < 0.001). The duration of the LH surge (64.8 .+-. 2.2 h) and LH peak levels (136 .+-. 9.6 mIU/ml) in the oestrogen treated cycles were similar to those in the control cycles (61.2 .+-. 3.9 and 119 .+-. 9.4 mIU/ml respectively) (mean .+-. SEM). The cycle day on which the LH surge started and the size of the dominant follicle, as assessed by ultrasound, did not differ significantly between the two groups of cycles. These results show that in spontaneous cycles the endogenous LH surge is neither reduced nor amplified by the induction of supraphysiological serum E2 levels during the immediate pre-ovulatory stage.This publication has 23 references indexed in Scilit:
- Disparate effects of endogenous and exogenous oestradiol on luteal phase function in womenReproduction, 1987
- ENDOGENOUS LUTEINIZING HORMONE SURGE IN WOMEN DURING INDUCTION OF MULTIPLE FOLLICULAR DEVELOPMENT WITH PULSATILE FOLLICLE STIMULATING HORMONEClinical Endocrinology, 1986
- Endogenous Luteinizing Hormone Surge during Superovulation Induction with Sequential Use of Clomiphene Citrate and Pulsatile Human Menopausal GonadotropinJournal of Clinical Endocrinology & Metabolism, 1985
- Human menopausal gonadotropin stimulation in monkeys: blockade of the luteinizing hormone surge by a highly transient ovarian factorFertility and Sterility, 1984
- Induction of Midcycle Gonadotropin Surge by Ovarian Steroids in Women: A Critical Evaluation*Journal of Clinical Endocrinology & Metabolism, 1983
- Hormonal Dynamics at Midcycle: A Reevaluation*Journal of Clinical Endocrinology & Metabolism, 1983
- Roles of Estradiol and Progesterone in Eliciting the Midcycle Luteinizing Hormone and Follicle-Stimulating Hormone Surges*Journal of Clinical Endocrinology & Metabolism, 1979
- Experimental studies on the positive feedback effect of progesterone, 17?-hydroxyprogesterone and 20?-dihydroprogesterone on the pituitary release of LH and FSH in the human femaleArchiv für Gynäkologie, 1976
- Induced LH Surges in the Rhesus Monkey: Strength-Duration Characteristics of the Estrogen Stimulus12Endocrinology, 1973
- EXPERIMENTAL STUDIES ON THE ENDOCRINE REGULATIONS DURING THE PERIOVULATORY PHASE OF THE HUMAN MENSTRUAL CYCLEActa Endocrinologica, 1972