Thyroid disorders which has increased incidence in females, were found to effect coagulation- fibrinolytic system. In the present study an effort is made to evaluate the alterations of certain haemostatic parameters in overt hypothyroid patients.

Bleeding time, clotting time & platelet count were estimated in hypothyroid subjects and control group, with sample size of 15 each. Hypothyroid group included subjects with low FT₃, FT₄ & elevated TSH value (mean 14.9 mU/L).Both the groups were age and sex matched. The results showed prolonged bleeding time and clotting time which were statistically significant with p-value of <0.0001 for both the parameters each. In the present study, hypothyroid group showed decreased platelet count when compared to control group which was statistically significant with a p-value of <0.0001.This finding was in contrast to many of the previous studies which showed either increase in platelet count or even if there was decrease, it was statistically not so significant.

This shows increased bleeding tendency or hypocoagulable state in overt hypothyroid patients. The more elevated the TSH levels, the more the deviation of haemostatic parameters from normal.

Key-words: Hypothyroidism FT₃, FT₄, TSH, haemostasis, bleeding time, clotting time, platelet count

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Dr Lanke Vani

Assistant Professor, Department of Physiology,

Guntur Medical College, Guntur, A.P India

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