Spina Bifida is an incomplete closure in the spinal  column.  There are three types of spina bifida. In general, the three types (from mild to severe) are:

Spina Bifida Occulta: There is an opening in one or more of the vertebrae (bones) of the spinal column without apparent damage to the spinal cord.
Meningocele: The meninges, or protective covering around the spinal cord, has pushed out through the opening in the vertebrae in a sac called the meningocele; However, the spinal cord remains in tact. This form can be repaired with little or no damage to the nerve pathways.
Myclomeningocele: This is the most severe form of spina bifida, in which a portion of the spinal cord itself protrudes through the back. In some cases, sacs are covered with skin; in others, tissue and nerves are exposed. Generally, people use the terms; spina bifida; and myelomeningocele; interchangeably.

The effects of myelomeningocele, the most serious form of spina bifida, may include muscle weakness or paralysis below the area of the spine where the incomplete closure (or cleft) occurs, loss of sensation below the cleft, and loss of bowel and bladder control.  In addition, fluid may build up and cause an accumulation of fluid in the brain (a condition known as hydrocephalus).  Large percentages (70% – 90%) of children born with myelomeningocele have hydrocephalus.

A surgical procedure called “shunting” helps control hydrocephalus by relieving the fluid buildup in the brain.  If a shunt is not implanted, the pressure buildup can cause brain damage, seizures or blindness.  Hydrocephalus may occur without spina bifida, but the two conditions often occur together.

Who is at risk?

Birth defects can happen in any family.  In the United States, there are 60 million women of childbearing age, and each one is potentially at risk of having a pregnancy affected by spina bifida.