Folic acid is a vitamin that is necessary to create new cells in the body and is used by the developing baby.
The body does not store very much folic acid so a regular supply is essential to stay healthy and is crucial for those in the very early stages of pregnancy.
Supplements of the vitamin both before and during early pregnancy help to reduce the risk of neural tube defects such as spina bifida in the foetus as the baby's spinal cord requires a regular supply.
Commonly, the advice is to start taking folic acid as soon as you plan to become pregnant but if unplanned, it should be taken as soon as you are aware of the pregnancy.
For most women a dose of 0.4mg a day is sufficient, though if you are at high risk of having a child with a spinal cord problem, the dose should be increased (see your doctor as you may need a prescription).
Folic acid supplements are available from the majority of pharmacies but your supply can also be boosted through your normal diet.
Vegetables such as spinach, sprouts, broccoli and green beans contain the vitamin while it is also possible to find breakfast cereals that are fortified with folic acid.