Effect of thyroid hormone replacement therapy on ovarian volume and androgen hormones in patients with untreated primary hypothyroidism

Abstract

BACKGROUND AND OBJECTIVES:Primary hypothyroidism may be associated with ovarian enlargement and/ or cyst formation. We evaluated the effect of thyroid hormone replacement therapy on hormonal changes, ovarian volume and sonographic appearance.DESIGN AND SETTING:Open, prospective study of women admitted to university gynecology clinic.PATIENTS AND METHODS:The study included 26 patients with untreated hypothyroidism who had polycystic (n=10) or normal-appearing (n=16) ovaries and 20 euthyroidic controls. Basal serum total testosterone, free testosterone, androstenedione, dehydroepiandosterone-sulfate, prolactin, estradiol, luteinizing hormone, follicle-stimulating hormone, free T3, free T4 and thyroid-stimulating horone, together with ovarian volumes, were determined and repeated after euthyroidism was achieved.RESULTS:Ovarian volumes of patients with hypothyroidism were significantly greater compared with controls, and their magnitudes diminished significantly during thyroid hormone replacement therapy. Hypothyroidic patients with polycystic ovaries had significantly higher serum free testosterone and dehydroepiandosterone-sulfate, but lower androstenodione levels compared with those who had normal-appearing ovaries. Serum total testosterone concentrations were significantly higher in hypothyroidic patients without polycystic ovaries, and thyroid hormone replacement therapy achieved a significant reduction in total as well as free testosterone.CONCLUSION:Severe longstanding hypothyroidism leads to increased ovarian volume and/or cyst formation. A decrease in ovarian volume, resolution of ovarian cysts and reversal of the polycystic ovary syndrome-like appearance, together with improvement in serum hormone levels, occurred after euthyroidism was achieved.

Hypothyroidism Reduces the Size of Ovarian Follicles and Promotes Hypertrophy of Periovarian Fat with Infiltration of Macrophages in Adult Rabbits

“…In contrast to those studies in humans and animals in which hypothyroidism promotes the formation of cystic follicles [34, 35], we did not find more cystic follicles in hypothyroid rabbits. However, it is important to take into account that rabbits are reflex ovulators [36] and females used in this study were at early proestrus [15].…”

Relationship between TSH, T4, T3 and Prolactin in overweight and lean Sudanese PCOS Patients

“…Besides this, hypothyroidism could be the reason behind PCOS in those patients. Muderris et al [22] stated that severe prolonged hypothyroidism contributes to bigger ovarian size and/or cyst formation, and additionally, restoration inserum hormone levels owing to accomplishment of euthyroidism, induces a reduction in ovarian size, resolve of ovarian cysts together with reversal of the polycystic ovary syndrome-like characteristics. At the same time, the study was consistent with Ghosh et al [23] who, in intending to analyze the part of hypothyroidism in the causation of PCOS, proposed that hypothyroidism resulted in reducing of sex hormone binding globulin level and increment of testosterone level.…”

Thyroid disorders and polycystic ovary syndrome: An emerging relationship

“…In a study, on somewhat less severe primary hypothyroidism, by Muderris et al ., 26 treatment naïve females with primary hypothyroidism, with mean TSH 57.1 mcg/dl, underwent evaluation of ovarian volume before and after replacement with thyroxine. [ 6 ] Twenty-six healthy normal controls were also recruited. Ten of 26 hypothyroid females had polycystic appearing ovaries on ultrasound sonography test at baseline.…”