Have been diagnosed to have Hypothyroidism? Since when are you on medications if you are?  Please continue your medications for thyroid problem. Check your thyroid hormones periodically as per your General Physician advice. They should reach the desired values. Reaching the deisred values- it is individual specific and may take a few months. Meanwhile get in touch with a gynaecologist and follow her advice if your monthly periods are irregular. In addition to medications any form of exercise helps you in reducing weight.  This also has a major impact on periods regularity and conception. It would be great if you can share your medical history like - weight,  height, married life- how many years, thyroid values , medications that you are on.