Meningocele is a type of spina bifida, a birth defect where the baby’s spinal column doesn’t close completely during early pregnancy. What happens in meningocele? • The bones of the spine (vertebrae) don’t form properly. • A sac or swelling forms on the baby’s back. • This sac contains meninges (the protective membranes around the spinal cord) and cerebrospinal fluid, but the spinal cord itself usually stays in place. • Because the spinal cord is not inside the sac, nerve damage is usually less