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Updated: Jul 11, 2026

Remote Neuronal Activation Coupled with Automated Blood Sampling to Induce and Measure Circulating Luteinizing Hormone in Mice
Published on: August 25, 2023
Luteinizing hormone pulsatility in patients with major ovarian hyperandrogenism
A Bachelot1, K Laborde, J L Bresson
1Endocrinology, Pitié-Salpétrière Hospital, 83 boulevard de l'Hôpital, 75013, Paris, France.
Abstract:
Hyperandrogenism and ovulatory dysfunction are common in women with either polycystic ovary (PCOS) or ovarian virilizing tumor. However, contrasting with the numerous studies that have extensively described gonadotropin secretory abnormalities, principally increased LH pulse amplitude and frequency, few studies have concerned gonadotropin secretion in patients with ovarian virilizing tumors; low gonadotropin levels have occasionally been reported, but never extensively studied. The goal of the present study was to further evaluate the pulsatility of LH secretion in women with ovarian virilizing tumor compared with that of PCOS patients. Eighteen women with major hyperandrogenism (plasma testosterone level >1.2 ng/ml) were studied (5 women with ovarian virilizing tumor, 13 women with PCOS, and 10 control women). Mean plasma LH level, LH pulse number and amplitude were dramatically low in patients with ovarian tumors when compared to both PCOS (p<0.001) and controls (p<0.001). In case of major hyperandrogenism, LH pulse pattern differs markedly between women with ovarian virilizing tumor or PCOS, suggesting different mechanisms of hypothalamic or pituitary feedback.
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