MATWAS JOURNAL OF THE CLIMACTERIC & POSTMENOPAUSE ELSEVIER Maturitas 26 (1997) 133-138 Difference of LH and FSH secretory characteristics and degree of concordance between postmenopausal and aging women Alessandro D. Genazzan?*, Felice Petraglia”, Laura Sgarbi”, Vanna Montaninib, Beda Hartman&, Nicola Suricod, Andrea Biolcati’, Annibale Volpe”, Andrea R. Genazzanif “Pll~~siopathology of Human Reproduction, University of Modena, Via de1 Poz:o 71, 41100 Modena, Ita1.v bEndocrinolog.v Unit, University of Modena, Via de1 Pozo 71, 41100 Modena, Italy ‘Department of Obstetrics and Gynecology. University of Wien. Wien. Austriu ‘Department of Obsterrics and Gynecology, University of Nooara. Novura, Ital) ‘Department of Geriatrics, Uniuersirv of Norara, Novara. Ital, ‘Department of Obstetrics and Gynecology, Unioersity of Piss, Pisa, Ital> Received 9 May 1996: revised 11 September 1996: accepted 24 October 1996 Abstract Objectice: Severalneuroendocrine changes occur at menopause and the presentstudy aimedto verify whether the episodic release and the degreeof concordance of LH and FSH differs betweenearly and late postmenopausal women. Methods: Postmenopausal (n = 32) women were enrolled and subdivided in two groups according to the menopausal age:group A (n = 22), patients with more than 2 but less than 5 yearsfrom the occurrence of menopause; group B (n = lo), patients with more than 15 years from the occurrence of menopause. All subjects underwent a pulsatility study (4 h, sampling every 10 min) to assess LH and FSH secretory characteristics and their degree of concordance. Results: Mean + S.E.M. LH and FSH plasma levels werelower in older women than in postmenopausal women (P < 0.01). The secretorypattern was pulsatilefor both LH and FSH and their pulseamplitudes were lower in aged women (P < 0.01). No significantdifference wasobserved in termsof pulse frequencybetween the two groups. LH and FSH pulses were co-secreted in early postmenopausal women while such a concordance was lost in older women. Conclusions: Late postmenopause is characterized by the reduction of the amplitudeof gonadotropin pulses in comparison to women in early postmenopause. reflecting changes of both GnRH secretion and/or pituitary responsiveness to GnRH. The age-related loss of concordance between LH and FSH pulses discloses the existence of a hidden FSH stimulatingsystem, which drives FSH episodic release independently and more promptly than GnRH. 8 1997 Elsevier Science Ireland Ltd. Ke.v~tvd.~: Luteinizing hormone; Follicle stimulatinghormone; Early postmenopause; Late postmenopause * Corresponding author. Fax: + + 39 59 371401; e-mail: algen@,c220.unimo.it 037%5127:97!$17.00 0 1997 Elsevier Science Ireland Ltd. All rights reserved PIISO378-5122(96)01088-2