What is spina bifida?

Spina bifida literally means ‘split spine’. A fault in the development of the spinal cord and surrounding bones (vertebrae) leaves a gap or split in the spine. The spinal cord has not formed properly, and may also be damaged. To help understand what it is, it is useful to explain the composition of the nervous system.

The central nervous system

The central nervous system consists of the brain and the spinal cord. Everything we do, and unconscious functions like maintaining body temperature, are controlled by the brain which receives information from touching, seeing, feeling, tasting and hearing, then responds to this information by moving the body etc. Messages from the brain are carried to different parts of the body via the spinal cord which runs down the centre of the spinal column, and then to  all parts of the body by pairs of nerves emerging at each vertebra.

The spine

The spine is made up of 33 bones or vertebrae. The vertebrae have two main functions. One is to provide anchorage for muscles so that we can move as the brain dictates to those muscles. The other is to protect to the spinal cord.

The neural tube

The central nervous system and spine develops very early in the pregnancy, between the 14th and 23rd day after conception. Spina bifida occurs when the neural tube, the structure in the embryo that becomes the brain and spinal cord, fails to close correctly. The vertebrae also fail to form complete rings around the affected portion of the spinal cord. This leaves a gap at the back, involving one or more vertebrae. The fault may occur in one or more of the vertebrae but it is most common around waist-level.

Why does spina bifida happen?

At present we don’t know why spina bifida develops, and research continues.

However, we do know that taking folic acid supplements before getting pregnant can reduce the risk of spina bifida in unborn babies. For families with no history of spina bifida the Department of Health recommends women take an ‘over the counter’ dose of 400mcg daily. For families where there is a history of spina bifida, a prescription dose (5mg) of folic acid is needed.

Folic acid should be taken daily for at least one month prior to conception and through to the 12th week of pregnancy.

The exact reasons why the neural tube develops incorrectly are not yet known but it is probably connected with both genetic and environmental factors. Shine also recommends taking a supplement of B12 (2.5mcg or more) for three months before pregnancy. For more, see Shine’s information about prevention.

Types of spina bifida

You may not know, but there are a number of different types of spina bifida.  We’ve listed them here along with an explanation of what each one means.

Learn more about the condition

Need more help?

If you need to speak with one of Shine’s specialist advisers about spina bifida or hydrocephalus, call us on 01733 555988 or click here to email us.

Our office hours are Monday to Friday, 9am to 5pm. We aim to respond to all enquiries as quickly as possible!

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