I can understand your concern regarding weight. Hyperthyroidism was actually responsible for miscarriage. You must ensure your thyroid is functioning normally before you plan another pregnancy. In order to gain weight, first your thyroid problem must be resolved because as long as you have an overactive thyroid, weight gain will be difficult. You must eat a healthy diet rich in starchy foods like rice, potatoes, bananas, mangoes etc. Have less fibre and more starch containing foods. If you have a low appetite avoid taking fluids just before meals. Eat small frequent meals throughout the day to ensure adequate intake of calories. Avoid too much of fried and fatty foods which delay digestion reducing appetite. You can have them but in limited amounts especially if you are a poor eater. Have thick fruit milkshakes. You can add ice cream and skimmed milk powder to increase calories as well as protein content of shakes. Use bananas, chickoos, mango, strawberries for preparing milk shakes. Use whole milk instead of low fat milk. Have easily digestible cereals like rice, semolina or sooji(hindi), white bread sandwiches, cottage cheese or paneer (hindi). If you are a non-vegetarian, then you can have mutton, chicken, fish and eggs. There is no such restriction in your diet but you must avoid high fibre diets as they will make you feel full without giving adequate calories needed for gaining weight. Rest well and don t take stress. Take care.