there is as such no need for the medication for the control of the weight. as u are breast feeding the child it doesnt seems wise neither for you nor for your child to take the medication for weight reduction. the best way for the weight reduction is proper diet & exercises. As you are having both hypothyroidism as well as the PCOS ( Polycysic ovaries ) both of which are the conditions which are favouring the weight gain you may have the trouble of gaining weight. But weight reducion by any of the means I mentioned above wil not only check your weight but also decrese the medication dependance for the above metioned pathologies. redusing weight its self helps to correct hypothyroidism & PCOS. The only thing what you have to do is modification of diet which should contain more and more fibrous diet with green leafy vegetables, reduction in cheeze, butter& other milk products & reduction in junk foods. About exercise Yoga is the best if not possible the brisck walking ( means fast wlak as if you are in hurry of cathcing the bus) daily for about 3 to 5 kms would suffice. It will definitly bring down your weight by 2- 3 kgs within span of 2 months.