Spina Bifida

  1. Overview — What is Spina Bifida?
  2. Causes and Prevention
  3. Prenatal Diagnosis
  4. Associated Conditions
  5. Motor and Sensory Function
  6. Bladder and Bowel Management
  7. Fetal Surgery
  8. Postnatal Surgery and Care
  9. Life with Spina Bifida
  10. Key Research Papers
  11. Connections
  12. Featured Videos

Overview — What is Spina Bifida?

Spina bifida is a neural tube defect (NTD) — a birth condition caused by incomplete closure of the neural tube during the first weeks of embryonic development. The neural tube is the embryonic structure that becomes the brain, spinal cord, and the bones and tissue that surround them. In spina bifida, part of the spinal column fails to close fully, leaving the underlying spinal cord and nerves vulnerable. This process happens between days 21 and 28 after conception — often before a person even knows they are pregnant.

Spina bifida exists on a spectrum, ranging from a mild form many people live with unknowingly to a serious form requiring immediate surgery at birth:

In the United States, spina bifida affects approximately 3.05 out of every 10,000 live births. Rates have declined substantially since 1998, when the US began requiring folic acid fortification of enriched grain products — a public health milestone that has saved thousands of children from neural tube defects. Despite this progress, spina bifida remains one of the most common serious birth defects in the country.

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Causes and Prevention

Spina bifida arises from a combination of genetic and environmental factors. No single cause accounts for all cases, but several risk factors are well established — and the most important one is highly preventable.

Folic Acid — The Most Important Modifiable Risk Factor

Adequate folic acid (vitamin B9) in the weeks before and immediately after conception is the single most powerful tool for preventing neural tube defects. Because the neural tube closes in the first 28 days after conception — before most pregnancies are confirmed — folic acid must be present before conception occurs, not just after a positive test.

Genetic Factors

Spina bifida is more common in families where NTDs have already occurred. A parent or sibling with spina bifida increases the risk in subsequent pregnancies to roughly 2–3% (compared to the general population baseline of about 0.1%). Chromosomal abnormalities are found in a minority of cases. Variants in the MTHFR gene impair the body's ability to process folate into its active form, raising NTD risk — particularly when dietary folate intake is low.

Maternal Medications

Valproate (valproic acid, Depakote), an anti-epileptic and mood-stabilizer, carries the highest medication-associated NTD risk: approximately 1–2% per exposed pregnancy. It should be avoided in people of childbearing age whenever a safer alternative exists. Carbamazepine also carries an elevated (though lower) NTD risk. Women with epilepsy who require these medications should discuss risks with both their neurologist and obstetrician before becoming pregnant.

Other Maternal Risk Factors

Race and Ethnicity

Hispanic individuals in the United States have the highest rates of spina bifida, followed by non-Hispanic white individuals. Non-Hispanic Black individuals have lower rates. The reasons for these disparities are not fully explained and likely reflect a combination of genetic variation and differential access to folic acid-fortified foods.

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Prenatal Diagnosis

Modern prenatal care offers several ways to detect spina bifida before birth. A prenatal diagnosis changes nothing about your child's inherent worth — but it allows families to prepare emotionally, make informed decisions, plan delivery at a specialized center, and arrange immediate postnatal care, all of which improve outcomes.

Maternal Serum Alpha-Fetoprotein (MSAFP)

This blood test, drawn between 15 and 20 weeks of pregnancy, measures alpha-fetoprotein (AFP) — a protein produced by the fetus. In open neural tube defects (meningocele and myelomeningocele), AFP leaks into the amniotic fluid and then into the mother's bloodstream, causing elevated MSAFP levels. An elevated result triggers further evaluation — it is a screening test, not a diagnosis. MSAFP is part of the standard second-trimester quad screen offered to all pregnant people in the US.

Amniocentesis

When MSAFP is elevated or clinical suspicion is high, amniocentesis can be performed to measure AFP and acetylcholinesterase directly in the amniotic fluid. The combination of elevated amniotic fluid AFP plus positive acetylcholinesterase is highly specific for an open neural tube defect and is considered diagnostic.

Level 2 Ultrasound (Anatomy Scan)

The detailed fetal anatomy ultrasound performed at 18–20 weeks is often where spina bifida is first identified. Two characteristic ultrasound findings are virtually diagnostic of myelomeningocele:

Direct visualization of the spinal defect confirms the diagnosis and helps define the level of the lesion, which predicts functional outcome. Fetal MRI provides detailed characterization of the defect level, brain anatomy, and associated anomalies when ultrasound findings are ambiguous.

Why Prenatal Diagnosis Matters

A confirmed prenatal diagnosis allows the family and medical team to plan delivery at a hospital with a neonatal intensive care unit (NICU) and immediate access to neurosurgery. It also opens the door to fetal surgery — an option that must be considered by 25 weeks of gestation (see Section 7). Arriving at a specialized center prepared is associated with significantly better early outcomes than an emergency transfer after birth.

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Associated Conditions

Myelomeningocele is rarely an isolated finding. Most children with MMC live with several associated conditions that require their own ongoing management. Understanding these from the start helps families navigate the medical system with confidence.

Hydrocephalus

Hydrocephalus — accumulation of cerebrospinal fluid (CSF) in the ventricles of the brain — occurs in 80–90% of children with MMC. It results from impaired CSF circulation related to the Chiari II malformation. Most affected children require a ventriculoperitoneal (VP) shunt, a small tube that drains excess fluid from the brain to the abdomen. Shunts are life-saving but carry a lifelong risk of malfunction. Parents should know the warning signs: headache, vomiting, excessive sleepiness, downward deviation of the eyes ("sunset sign"), or a change in behavior. Any of these warrants immediate emergency evaluation — shunt malfunction is a neurosurgical emergency. An alternative called endoscopic third ventriculostomy (ETV) creates a new CSF drainage pathway without a shunt and avoids lifelong shunt dependence in some children.

Chiari II Malformation

Nearly all children with MMC have Chiari II malformation — the lower portion of the brainstem and cerebellum is pushed downward through the base of the skull (the foramen magnum). Most children are asymptomatic, but some develop complications including apnea or breathing pauses, stridor (a high-pitched breathing sound), difficulty swallowing, arm weakness, or neck pain. Symptomatic Chiari II may require surgical decompression to relieve pressure on the brainstem.

Tethered Spinal Cord

After back closure surgery, scar tissue can adhere to and "tether" the spinal cord, preventing it from moving normally as the child grows. Tethering causes progressive neurological deterioration — worsening leg strength, worsening bladder function, or new back/leg pain — typically noticed during rapid growth phases. Surgical release of the tethered cord halts or reverses deterioration in most children.

Orthopedic Manifestations

The level and degree of muscle imbalance caused by MMC determines which orthopedic issues arise. Common problems include hip dislocation, clubfoot (talipes equinovarus), scoliosis (sideways spinal curvature), and kyphosis (forward curvature). Regular orthopedic evaluation guides the use of bracing, physical therapy, and surgical correction.

Latex Allergy

Between 40–70% of children with MMC develop a latex (natural rubber) allergy — one of the highest rates of any population group. The allergy develops through repeated exposure to latex products during surgeries, catheterizations, and medical exams from infancy onward. Reactions can be severe, including anaphylaxis. All medical care for children with spina bifida must be latex-free from the very first surgery. Children should wear a medical alert bracelet indicating latex allergy, and parents should inform every healthcare provider, dentist, and school nurse. Latex-free gloves, catheters, and equipment are now standard in specialized centers.

Skin Breakdown

Because skin below the level of the spinal lesion has reduced or absent sensation, children with MMC cannot feel pressure, friction, or heat in those areas. This makes them highly vulnerable to pressure ulcers and burns. Regular skin checks, appropriate padding on wheelchairs and braces, and teaching children to check their own skin as they grow are essential preventive habits.

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Motor and Sensory Function

The most frequent question families have after a diagnosis of myelomeningocele is: Will my child walk? The honest answer depends primarily on the level of the spinal defect — specifically, which nerve roots are involved. The higher the lesion on the spine, the more function is affected below it.

Understanding Lesion Levels

Spinal nerve roots are named by region (thoracic/T, lumbar/L, sacral/S) and numbered top-to-bottom within each region. The key motor milestones by level are:

Ambulation in Practice

Across all lesion levels, approximately 85–90% of children with MMC achieve some level of walking with appropriate orthoses and therapy — though community ambulation, household-only walking, and full wheelchair use exist on a spectrum. What matters most is not whether a child uses a wheelchair but whether they can move through their world safely and independently. Many children use a combination of mobility aids depending on the setting — walking at home, using a wheelchair for longer distances. Both are valid and successful outcomes. Physical therapy from birth is essential to maximize strength, range of motion, and motor development.

Sensory Considerations

Sensory loss mirrors motor loss: the area below the lesion level typically lacks normal pain, temperature, and pressure sensation. This has safety implications (burns, pressure injuries, unrecognized fractures) and means that physical therapy and orthopedic equipment must be fitted carefully by providers experienced with spina bifida.

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Bladder and Bowel Management

Bladder and bowel management is arguably the most important long-term health priority for people with myelomeningocele — more than mobility. Without effective bladder management, kidney damage accumulates silently and becomes the leading cause of serious morbidity and early death in MMC. With consistent management, most people protect their kidneys for life and achieve social continence.

Neurogenic Bladder

The sacral nerve roots that control the bladder are affected in virtually all MMC cases regardless of lesion level. The result is neurogenic bladder — the bladder does not empty or store urine normally. The most dangerous pattern is a high-pressure, overactive bladder that forces urine back up into the kidneys (vesicoureteral reflux), causing progressive kidney scarring.

Clean Intermittent Catheterization (CIC) is the cornerstone of management. A small catheter is inserted into the bladder at regular intervals (typically every 3–4 hours during waking hours) to drain urine fully. Parents learn to perform CIC in the hospital after birth and teach their child to do it themselves as they develop the dexterity, usually by age 6–8. CIC is not painful — the insensate urethra means the child feels little or nothing. Done consistently, CIC prevents UTIs, keeps bladder pressures low, and protects the kidneys.

Anticholinergic medications (most commonly oxybutynin) relax the bladder muscle, reducing the high-pressure contractions that cause reflux. Urodynamic studies — tests that measure bladder pressure and function — are performed periodically to guide medication adjustments and surgical decisions. Annual renal ultrasound monitors the kidneys for dilation or scarring throughout childhood and adult life.

For children who need a more reliable catheterization route, the Mitrofanoff appendicovesicostomy creates a small channel using the appendix that connects the bladder to a tiny opening in the abdomen or umbilicus — allowing catheterization through the belly rather than the urethra, which is particularly helpful for wheelchair users and those with limited hand dexterity.

Neurogenic Bowel

The same nerves that control the bladder also control the rectum and sphincter. In MMC, this results in neurogenic bowel — a combination of constipation (slow transit, weak propulsion) and fecal incontinence (impaired sphincter control). Left unmanaged, this affects quality of life enormously and creates social barriers at school and work.

Bowel management programs use a predictable schedule, dietary fiber, adequate hydration, and if needed, rectal stimulation or suppositories, to achieve planned bowel movements at a consistent time — typically once daily. Peristeen transanal irrigation (a wash-out system using water introduced through the rectum) is effective for many children and adults. For those who do not achieve continence with conservative measures, the Malone Antegrade Continence Enema (MACE) procedure creates an appendicostomy — a channel through the abdominal wall to the cecum — through which a wash-out can be given from above. Social continence is achievable for most children and adults with spina bifida with a committed, consistent management program.

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Fetal Surgery

One of the most significant advances in the treatment of myelomeningocele has been the development of fetal surgery to repair the defect before birth. The landmark MOMS Trial (Management of Myelomeningocele Study), published in the New England Journal of Medicine in 2011, was a randomized controlled trial comparing prenatal repair to standard postnatal repair in 183 families at three specialized US centers.

What the MOMS Trial Found

Children whose MMC was repaired before birth had significantly better outcomes at 30 months of age:

Maternal Risks and Eligibility

Fetal surgery carries real risks for the mother and pregnancy. Prenatal repair children were born at an average gestational age of 34 weeks (premature) vs. 37 weeks in the postnatal group. Risks include preterm labor, uterine dehiscence (surgical wound separation during the current or a future pregnancy), and the need for cesarean delivery in all future pregnancies. Strict eligibility criteria apply:

Emerging Approach: Fetal Endoscopic Repair

Open fetal surgery requires a large incision in the uterus. A newer approach called fetoscopic endoscopic repair (FETENDO) uses small ports and a camera to repair the defect through tiny incisions — reducing uterine scarring and maternal risk while achieving outcomes that are approaching those of open repair in recent case series. Fetoscopic MMC repair is now offered at a growing number of specialized centers worldwide.

Seeking Fetal Surgery Consultation

If spina bifida is diagnosed prenatally, families should seek consultation at a fetal surgery center as early as possible and ideally by 20 weeks — the eligibility window closes at 26 weeks. Even families who ultimately choose postnatal repair benefit from the comprehensive planning, delivery at a specialized center, and access to a full multidisciplinary team that fetal surgery centers provide.

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Postnatal Surgery and Care

For babies whose MMC is repaired after birth — whether because fetal surgery was not pursued or not appropriate — the first hours and days of life involve careful management to protect the exposed spinal tissue and prevent infection.

Immediate Newborn Care

Back Closure Surgery

The MMC defect is surgically closed within 24–72 hours of birth. The neurosurgeon carefully dissects and protects functioning neural tissue, closes the spinal cord in layers, and covers it with skin grafts if needed. Earlier closure reduces infection risk and preserves neurological function.

Hydrocephalus Management

Most babies with MMC develop hydrocephalus in the days to weeks after back closure as CSF dynamics shift. A VP shunt is typically placed within the first one to two weeks after back closure if hydrocephalus progresses. In select cases, endoscopic third ventriculostomy (ETV) with or without choroid plexus cauterization (ETV/CPC) can treat hydrocephalus without a shunt, avoiding lifelong shunt dependence — though not all children are candidates.

The Multidisciplinary MMC Clinic

Children with MMC thrive best when followed at a multidisciplinary spina bifida clinic that brings together specialists in a single visit:

These clinics coordinate care, reduce the burden of separate appointments, and ensure that the specialists managing different systems communicate with each other. Asking your hospital specifically for a "spina bifida clinic" or "MMC clinic" is one of the most important steps a family can take.

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Life with Spina Bifida

Adults with myelomeningocele lead full, meaningful lives — they attend college, pursue careers, form relationships, and become parents. The challenges are real, but with consistent medical management and strong support, they are navigable. This section addresses the questions families often ask as their child grows.

Transition to Adult Care

Adolescence brings a critical transition from pediatric to adult healthcare — and adult providers with spina bifida expertise are scarcer than pediatric ones. Planning this transition should begin in early adolescence, not at age 18. Specialized adult spina bifida clinics exist at some academic medical centers. The Spina Bifida Association maintains a provider directory at spinabifidaassociation.org.

Education and Cognition

Most children with spina bifida have normal intelligence, but many have specific learning differences — particularly in math, reading speed, attention, and visuomotor processing — that are related to the hydrocephalus and Chiari II malformation rather than to the spinal defect itself. An Individualized Education Program (IEP) or 504 accommodation plan can provide the support children need to succeed academically. Neuropsychological testing helps identify specific strengths and challenges.

Sexual Function and Reproductive Health

Sexual function is affected to varying degrees depending on lesion level. Those with sacral lesions often have near-normal function. Men with thoracic or lumbar lesions may have difficulty with erection and ejaculation, though assisted reproductive technologies (ART) can achieve paternity when needed. Women with spina bifida have normal fertility and can become pregnant. Pregnancy in women with MMC requires high-risk obstetric care, high-dose folic acid supplementation, and often delivery by cesarean section due to pelvic anatomy. Discussing sexual health openly with providers — using the same directness applied to any other organ system — is important for quality of life.

Mental Health and Peer Connection

Rates of depression and anxiety are elevated in both children and adults with spina bifida compared to the general population. Social isolation, visible difference, medical complexity, and the chronic unpredictability of conditions like shunt malfunction contribute to psychological burden. Peer mentorship — connection with other young people and adults living successfully with spina bifida — is one of the most powerful supports available. The Spina Bifida Association and its local chapters offer camps, youth programs, and adult peer networks. Seeking mental health support is not a sign of failure; it is part of comprehensive care.

Lifelong Surveillance Priorities

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Key Research Papers

  1. Adzick NS et al., 2011 — A randomized trial of prenatal versus postnatal repair of myelomeningocele (MOMS Trial) — N Engl J Med — PMID: 21306277
  2. Boulet SL et al., 2008 — Trends in the postfortification prevalence of spina bifida and anencephaly in the United States — Birth Defects Res A Clin Mol Teratol — PMID: 18829826
  3. Bowman RM et al., 2009 — Spina bifida outcome: a 25-year prospective — Pediatr Neurosurg — PMID: 19208933
  4. Liptak GS et al., 2001 — Outcomes of children with myelomeningocele in multidisciplinary clinics — J Pediatr Orthop — PMID: 11483878
  5. Szymanski KM et al., 2015 — Neurogenic bladder management in myelomeningocele — Urol Clin North Am — PMID: 26027468
  6. Mitchell LE et al., 2004 — Spina bifida — Lancet — PMID: 15213108
  7. Williams J et al., 1999 — Latex allergy in children with myelomeningocele — J Pediatr Surg — PMID: 9917445
  8. Merkler AE et al., 2016 — Tethered spinal cord syndrome in adults — J Neurol Neurosurg Psychiatry — PMID: 27167013
  9. Hunt GM, 1999 — Adults with spina bifida: a 40-year follow-up — Arch Dis Child — PMID: 10362774
  10. Johnson MP et al., 2012 — In utero surgical repair of myelomeningocele — Semin Pediatr Surg — PMID: 22285057
  11. Shaer CM et al., 2007 — Reproductive health of women with spina bifida — Sci World J — PMID: 17483555
  12. Shin M et al., 2010 — Decline in the prevalence of spina bifida and anencephaly after mandatory folic acid fortification in the US — Pediatrics — PMID: 20375408

PubMed Topic Searches

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  2. Folic acid neural tube defect prevention
  3. Myelomeningocele fetal surgery prenatal repair
  4. Neurogenic bladder spina bifida clean intermittent catheterization
  5. Spina bifida hydrocephalus VP shunt Chiari

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Connections

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