Postpartum thyroiditis is defined as a syndrome of transient orpermanent thyroid dysfunction occurring in the first year after deliveryand based on an autoimmune inflammation of the thyroid gland.Classically, it is in the form of a thyrotoxic phase is followed by ahypothyroid phase. During pregnancy, an enhanced state of autoimmunetolerance ensues, leading to an amelioration of existing thyroidautoimmunity. A rebound reaction to this pregnancy-associated immunesuppression. After delivery explains the aggravation of autoimmunesyndromes in the puerperal period e.g. the occurrence of clinically overtAll the 60 subjects either the control the patients groups were subjected to:-a) Clinical studies: which included history and clinical examination.b) Routine investigations.1- fasting and post prandial blood glucose level.2- Serum cholesterol and Triglycerides, complete blood picture, kidney function tests and liver function tests.3- X ray chest and heart (P-A view)c) Specific investigationsI- Standard 12- Leaded electrocardiograms:A- for calculation of QTc dispersion.B- for determination of left ventricular hypertrophy.II- Echocardiographic study for detection of left ventricular mass by M-mode and 2-D echo.