This article originally appeared in The Neurotransmitter, Dr. Grunch’s weekly newsletter.
Did you know that the part of a baby that becomes the brain and spinal cord closes up within the first 4 weeks of pregnancy [2]. For many women, that’s before the pregnancy test even turns positive.
When that closing doesn’t finish, the result is spina bifida. It’s one of the most common birth defects of the spine.
October is Spina Bifida Awareness Month, and today, Halloween, is its last day. So this week I’m walking you through what spina bifida is, how a simple daily vitamin lowers the risk, and what people born with it need as they grow from babies into adults.
What Is Spina Bifida? Think of a Zipper
Early in pregnancy, a flat strip of cells along the back of the embryo rolls up into a tube. We call it the neural tube. The top end becomes the brain, and the rest becomes the spinal cord. The bones of the spine then form around it like a protective case.
Picture zipping up a sleeping bag. Most of the time, the zipper runs all the way to the top. In spina bifida (Latin for “split spine”), part of the zipper never closes, usually low in the back. What happens next depends on how big the gap is and what slips through it.
There are three main types [2]:
Spina bifida occulta (”hidden” spina bifida): a small gap in the bones, with no opening or sac on the back. It usually causes no problems, and many people only find out by accident on an X-ray as adults, or never.
Meningocele: a sac of fluid pushes out through the gap, but the spinal cord stays where it belongs. There’s usually little or no nerve damage.
Myelomeningocele (open spina bifida): the sac holds part of the spinal cord and nerves. This is the most serious type. It can cause leg weakness or paralysis, numbness in the legs and feet, and bladder and bowel problems.
When most doctors say “spina bifida,” they mean myelomeningocele. That’s the type I’ll focus on for most of this issue.
Who It Affects
In the U.S., about 1,251 babies are born with spina bifida every year. That’s about 1 in every 2,857 births [1]. Hispanic mothers have the highest rate, followed by non-Hispanic white and non-Hispanic Black mothers [1].
Spina bifida isn’t only a childhood condition. In 2019, at least 92,551 insured people in the U.S. were living with it, and that count leaves out the hidden type [1].
The outlook has changed a lot. A well-known study followed children with myelomeningocele for 25 years, and at least 75% of them reached early adulthood [5]. Today, more than 85% survive into adulthood [6]. That means our job is to plan for a whole life, not just the first year.
What’s Happening in the Body
When the spinal cord is left open, the nerves at and below the gap don’t form or work normally, and they’re exposed during pregnancy. The level of the gap matters a lot. The higher it sits on the spine, the more of the body is affected.
Open spina bifida affects more than the back:
Hydrocephalus: many babies build up extra fluid in and around the brain. A neurosurgeon may place a shunt, a thin tube that drains that fluid to the belly, where the body absorbs it [7]. In the 25-year study, 86% of the children had a shunt, and 95% of those needed at least one shunt revision over the years [5].
Chiari II malformation: in most children with open spina bifida, the lower back part of the brain sits lower than normal, crowded down toward the neck [8].
Tethered spinal cord: normally the bottom of the spinal cord moves freely inside the spinal canal. In a tethered cord, it’s stuck in place. As a child grows, the cord gets stretched like a rubber band pulled tight, and that can damage nerves [7].
Bladder and bowel: the nerves that control the bladder and bowel often don’t work normally, which raises the risk of urinary tract infections [7].
Latex allergy: people with spina bifida are much more likely to be allergic to latex, so many care teams avoid latex from birth [8][9].
Worth knowing: at least 80% of children with open spina bifida don’t have learning disabilities [8].
Signs, Symptoms, and Red Flags
Open spina bifida is usually found before birth, on a routine ultrasound or a blood test during pregnancy. If not, it’s obvious at delivery. The hidden type is different. Sometimes the only clue is on the skin of a baby’s lower back: a tuft of hair, a dimple above the crease of the buttocks, a birthmark, or a small lump. Most of these turn out to be nothing, but point them out to your pediatrician.
For kids and adults living with spina bifida, the big thing to know is that it can change over time. A shunt can clog. A tethered cord can start pulling as a child grows. These changes can creep in slowly, so families learn to watch for them.
See a doctor right away (call 911 or go to the ER) if someone with a shunt has:
A bad headache, especially one that’s worse in the morning or wakes them up
Vomiting, especially with a headache or sleepiness
Unusual sleepiness, trouble waking up, confusion, or a personality change
Blurred or double vision
A seizure
In babies: a bulging soft spot, a head that’s growing fast, eyes that seem stuck looking down, or new fussiness
Fever, redness, or swelling along the path of the shunt
Call your spina bifida team within a few days if you notice [7]:
New or worsening back pain
New weakness in the legs or feet, or a change in walking
Changes in bladder or bowel control, like new leaking or more infections
A curve in the spine (scoliosis) that’s getting worse
The first list can mean a shunt isn’t working. The second can mean a tethered cord. Both can be treated, and catching them early protects function.
What the Evidence Says About Treatment
Surgery after birth. The standard treatment for open spina bifida is surgery to close the opening, usually within the first day or two of life. It protects the exposed nerves and lowers the risk of infection. It can’t bring back nerve function that’s already lost.
Surgery before birth. This is one of the biggest advances in my field in the last 15 years. In the MOMS trial, mothers carrying babies with myelomeningocele were randomly assigned to fetal surgery before 26 weeks of pregnancy or to standard repair after birth [4]. The results:
Only 40% of babies who had surgery before birth needed a shunt, compared with 82% of babies repaired after birth [4].
At 30 months old, 42% of the prenatal surgery group could walk without crutches or devices, compared with 21% [4].
That’s a real win, but it comes with trade-offs. Surgery before birth raised the risk of preterm birth and of thinning or opening at the scar on the uterus [4]. Not every pregnancy qualifies, and the decision belongs to the family and a specialized fetal center.
Treating hydrocephalus. Most children who need treatment get a shunt. Some can have a minimally invasive procedure that creates a new drainage path inside the brain instead. Either way, they’ll need a neurosurgeon to follow them for life.
Tethered cord surgery. When a tethered cord causes symptoms, surgery can release it [7].
The whole team. Good spina bifida care takes a team: neurosurgery, urology, orthopedics, rehab medicine, physical therapy, and mental health support. The Spina Bifida Association publishes care guidelines that cover everything from newborn care to adult life [9]. In the 25-year study, more than 80% of the young adults had social bladder continence, meaning they could stay dry day to day with a plan like catheterization [5].
Growing Up With Spina Bifida
Spina bifida care is built around kids, and many adults with spina bifida have a hard time finding doctors who know the condition well.
Updated transition guidelines say preparing for adult care should start around ages 12 to 14, with the hand-off to adult doctors usually between 18 and 21 [6]. The authors even say these conversations should begin at birth [6]. The gap is real. In one study, only 40% of young adults made it from a pediatric spina bifida clinic to an adult urology clinic [6].
Adults with spina bifida are as different as anyone else. By age 30, about one-third live independently, one-third need some supervision and occasional help, and one-third need regular help with daily care [6]. Every one of them deserves a doctor who knows their shunt history and their spine.
What You Can Do
If you could become pregnant: take a daily vitamin with 400 to 800 micrograms (0.4 to 0.8 mg) of folic acid. The U.S. Preventive Services Task Force gives this its highest grade, an A [3]. Start at least 1 month before you might get pregnant and keep going through the first 2 to 3 months [3]. Because the neural tube closes so early, waiting for a positive test can be too late.
Folic acid works. Since the U.S. started adding it to foods like enriched grains, these birth defects have dropped by about 28%, and the CDC estimates it prevents about 1,300 of them every year [1].
If you’ve had a pregnancy affected by spina bifida, have a strong family history, or take a medicine that blocks folic acid, the task force’s standard advice doesn’t apply to you [3]. Talk to your doctor before pregnancy, because you may need a different plan.
If you or your child has spina bifida:
Keep a one-page medical summary: type and level, shunt type and date, past surgeries, allergies (especially latex), and medicines.
Learn the signs of shunt failure and tethered cord, and share them with teachers, coaches, and partners.
Ask for latex-free care at every visit.
Start planning the move to adult care in the early teen years [6].
Questions to ask your doctor:
Do I (or does my child) have a shunt, and what are the warning signs it isn’t working?
How often should we check the shunt and spinal cord?
Who will manage my spina bifida care as an adult?
Is my folic acid dose right for a future pregnancy?
Should this dimple or patch of hair on my baby’s back be checked?
Key Takeaways
Spina bifida happens when the neural tube doesn’t fully close, and that closing happens within the first 4 weeks of pregnancy [2].
About 1,251 babies a year are born with spina bifida in the U.S., and more than 85% now live into adulthood [1][6].
A daily vitamin with 400 to 800 mcg of folic acid, started at least a month before pregnancy, lowers the risk [3].
In someone with a shunt, a bad headache, vomiting, unusual sleepiness, or vision changes is an emergency.
Surgery before birth can lower the need for a shunt and help kids walk, but it carries real risks for mom and baby [4].
Learn more about the conditions we treat, including hydrocephalus, Chiari malformation, and tethered cord syndrome, on our Conditions We Treat page.
References
Centers for Disease Control and Prevention. Data and statistics on spina bifida. Accessed October 30, 2026. https://www.cdc.gov/spina-bifida/data
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD). About spina bifida. Accessed October 30, 2026. https://www.nichd.nih.gov/health/topics/spinabifida/conditioninfo/default
US Preventive Services Task Force; Barry MJ, Nicholson WK, Silverstein M, et al. Folic acid supplementation to prevent neural tube defects: US Preventive Services Task Force reaffirmation recommendation statement. JAMA. 2023;330(5):454-459. doi:10.1001/jama.2023.12876
Adzick NS, Thom EA, Spong CY, et al. A randomized trial of prenatal versus postnatal repair of myelomeningocele. N Engl J Med. 2011;364(11):993-1004. doi:10.1056/NEJMoa1014379
Bowman RM, McLone DG, Grant JA, Tomita T, Ito JA. Spina bifida outcome: a 25-year prospective. Pediatr Neurosurg. 2001;34(3):114-120.
Fremion E, Kaufman M, Mukherjee S, Murphy P, Smith K. 2023 updates to the spina bifida transition to adult care guidelines. J Pediatr Rehabil Med. 2023;16(4):583-593. doi:10.3233/PRM-230052
Centers for Disease Control and Prevention. Health issues and treatments for spina bifida. Accessed October 30, 2026. https://www.cdc.gov/ncbddd/spinabifida/treatment.html
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD). Are there disorders or conditions associated with spina bifida? Accessed October 30, 2026. https://www.nichd.nih.gov/health/topics/spinabifida/conditioninfo/disorders-conditions
Spina Bifida Association. Guidelines for the care of people with spina bifida. Accessed October 30, 2026. https://www.spinabifidaassociation.org/guidelines/
Schedule an Appointment with Southern Neurosurgery
Have questions about your brain or spine health? Dr. Betsy Grunch and the team at Southern Neurosurgery are here to help. Call us at 470-293-9800 to schedule an appointment, or reach out through our Contact Us page.
Disclaimer: This article is for educational purposes only and is not medical advice. It does not replace individualized care from a licensed physician. If you have symptoms or questions about your own health, please consult your healthcare provider. If you think you are having a medical emergency, call 911.
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