First, discuss your problem with your doctor. He/she is the most appropriate person to suggest other supplements.
The increased iron requirements of pregnancy (30 milligrams) cannot be met by the iron content in your diet or by your existing iron stores in your body. An iron and folacin supplement is usually prescribed for pregnant women. So the bottom line is you still need the iron supplement.
Unfortunately, iron supplements often cause constipation. This presents added discomfort to the pregnant woman since her growing uterus is further cramping her intestines. You should increase the fiber and fluid content in your diet to help relieve constipation.
High fiber foods are whole wheat bread, whole cereal grains, fresh fruits, fresh vegetables, dried beans, and peas. Start including one or two high fiber foods in your daily diet.
Your fluid intake should be at least eight glasses of water per day. The fluid your baby is floating in changes completely every eight hours. The replacement water has to come from your body or your diet.
You should be eating more foods higher in iron. Liver, red meat, fortified cereals, prune juice, dried beans, and peas are the best sources of iron. Raisins and other dried fruits, liver sausage, prunes, spinach and beet greens, broccoli, peas, molasses and whole grain bread are moderate sources of iron. Many of these foods are also high in fiber, which would also help your problem with constipation.