RESUMO
Background: In females, hypothyroidism can cause menstrual disturbances mainly oligomenorrhea. Thyroid dysfunction has also been linked to reduced fertility and pregnancy complications. Several studies have been done to evaluate gonadal dysfunctions in overt hypothyroidism but very few studies are there regarding subclinical hypothyroidism. Present study evaluates the gonadal functions of women with subclinical hypothyroidism.Methods: Total 20 females of age 18 to 35 years with newly diagnosed subclinical hypothyroidism were taken as cases and 20 age and body mass index (BMI) matched healthy females were taken as controls. Both in cases and controls, basal FSH, LH, estradiol were measured on 3rd or 4th day of menstrual cycle at 8 AM on fasting. Thereafter Leuprolide 20 mcg/kg was given subcutaneously on the same day. One hour after injection, LH and estradiol were measured. Basal and stimulated values were compared between both groups.Results: Basal LH was significantly higher in controls (6.63�38 m IU/ml) when compared to cases (6.06�10 m IU) with a p value 0.01 (<0.05). No significant differences were found between stimulated LH and estradiol in both the groups.Conclusions: In mild thyroidal failure the response of pituitary gonadotrophs to leuprolide is normal in contrast to overt hypothyroidism where the response is sluggish. This is the first study to be done in subclinical hypothyroid subjects to asses both basal and stimulated gonadotropin levels. Further studies are required in large samples to confirm these findings.