During pregnancy, your body's needs become drastically different. You need nutrition for not just yourself but also for the baby. It is very important to take a proper diet but even that cannot sometimes cover the requirements. To make up for that, the doctor may advise certain supplements to keep you and the baby healthy. Iron, folic acid, calcium, vitamin D, vitamin C and more may be prescribed to provide better nutrition. Make sure you take the supplements regularly and according to the prescribed timetable and dosage. While you may be worried about the amount of supplements being sufficient, you must remember that even higher doses can be toxic. Don't self medicate, even in case of supplements, and seek advise of your doctor before starting any course.