Guideline sources The following summarized guidelines for the evaluation and management of myelomeningocele are prepared by our editorial team based on guidelines from the Society of Obstetricians and Gynaecologists of Canada (SOGC 2021), the Congress of Neurological Surgeons (CNS 2019), the American College of Obstetricians and Gynecologists (ACOG 2017), and the World Health Organization (WHO 2015). 1 2 3 4 5 Guidelines 1. Screening and diagnosis Indications for screening: as per SOGC 2021 guidelines, obtain second-trimester anatomical ultrasound with detailed fetal intracranial and spinal imaging as the primary screening technology https://web.pathway.md/diseases/recY3OoHHWCLfOthR 1/5 6/30/23, 1:06 AM Myelomeningocele Pathway to detect fetal structural abnormalities including open and closed neural tube defects (anencephaly, encephalocele, myelomeningocele, and other spina bifida malformations). B Show 4 more 2. Diagnostic investigations Diagnostic imaging: consider obtaining prenatal MRI if further detailed assessment of the fetal CNS is required for diagnostic or management counseling. B 3. Diagnostic procedures Amniocentesis: As per SOGC 2021 guidelines: Evaluate the amniotic fluid specimen for fetal genetic abnormalities, if a diagnostic amniocentesis is performed, following ultrasound detection of fetal anomalies including confirmed or suspected open or closed neural tube defects. Obtain chromosomal microarray and other genetic testing, as considered appropriate after assessment of fetal anomalies and family history, during evaluation with amniotic fluid AFP and amniotic fluid acetylcholinesterase, if required by protocols for fetal surgery decisions. A Consider obtaining fetal exome sequencing in fetuses with myelomeningocele or other spina bifida anomalies, only after multidisciplinary counseling and after appropriate criteria for molecular genetic sequencing are met. B Autopsy: perform autopsy following either termination of pregnancy or prenatal/postnatal death in all cases of myelomeningocele (isolated or complex) and other neural tube defects, to provide optimal counseling for the current pregnancy and future pregnancies and neural tube defect risk assessment for future pregnancies. A 4. Medical management Setting of care: As per SOGC 2021 guidelines, refer patients with positive screening results on imaging for an open or closed neural tube defect (ultrasound with or without maternal serum AFP) to experienced providers for confirmation, genetic/etiologic investigation and diagnosis, and pregnancy management counseling. A As per ACOG 2017 guidelines, refer interested candidates for fetal myelomeningocele repair for further assessment and consultation to a fetal therapy center offering this intervention and possessing the expertise, multidisciplinary team, services, and facilities to provide detailed information regarding maternal-fetal surgery and the intensive care required for patients choosing open maternal-fetal surgery. E https://web.pathway.md/diseases/recY3OoHHWCLfOthR 2/5 6/30/23, 1:06 AM Myelomeningocele Pathway Antibiotic prophylaxis for ventriculitis: initiate antibiotics if myelomeningocele closure is delayed beyond 48 hours. B 5. Therapeutic procedures Management of delivery: As per SOGC 2021 guidelines: Consider offering either Cesarean or vaginal delivery for fetuses with myelomeningocele in a vertex presentation. Individualize intrapartum care based on head size, myelomeningocele lesion size, lower limb position, and mobility considerations. C Perform a pre-labor Cesarean delivery at 37 weeks at the latest to prevent possible rupture of the hysterotomy scar during labor if prenatal myelomeningocele surgical repair is conducted. A 6. Surgical interventions General principles: as per SOGC 2021 guidelines, offer a choice of 3 obstetrical care management options in families with an isolated open/closed neural tube defect after diagnostic and genetic testing: prenatal surgical repair of myelomeningocele and prognosis postnatal surgical repair of myelomeningocele and prognosis pregnancy termination with autopsy. A Prenatal surgical closure: As per CNS 2019 guidelines: Perform prenatal closure of myelomeningocele, if possible, in patients with prenatally diagnosed fetuses with myelomeningocele meeting maternal and fetal MOMS inclusion criteria to improve ambulatory status for patients in short-term (at 30 months of age). B Recognize that long-term benefit for ambulatory status with prenatal closure is unknown. B As per ACOG 2017 guidelines, counsel women with pregnancies complicated by fetal myelomeningocele meeting established criteria for in utero repair in non-directive fashion regarding all management options, including the possibility of open maternal-fetal surgery. E Show 2 more 7. Preventative measures Periconceptional folic acid supplementation: as per SOGC 2021 guidelines, offer a diet of folate-rich foods and a daily oral multivitamin supplement containing 0.4 mg folic acid and vitamin B12 for at least 2-3 months before conception, throughout the pregnancy, and for 4-6 weeks postpartum or as long as breastfeeding continues in females at low risk for neural tube defects or other folic acid-sensitive congenital anomalies if the male partner also has a low risk. B https://web.pathway.md/diseases/recY3OoHHWCLfOthR 3/5 6/30/23, 1:06 AM Myelomeningocele Pathway Show 2 more 8. Follow-up and surveillance Post-closure follow-up: Obtain careful follow-up in patients with either prenatal or postnatal closure for the development of tethered spinal cord with the associated loss of ambulatory function. B Obtain continued surveillance for tethered cord syndrome and/or the development of inclusion cysts in patients with prenatal and postnatal closure of myelomeningocele. B Subsequent pregnancy planning: offer daily oral supplementation with 4.0-5.0 mg of folic acid in a multivitamin supplement containing vitamin B12 starting at least 3 months before conception and throughout the first trimester when either member of the couple has had an isolated neural tube defect or a previous pregnancy that involved a presumed folic acid-sensitive open or closed neural tube defect (no karyotype, chromosomal microarray or identified single-gene disorder). A Show 2 more 9. Quality improvement Optimal folat concentrations: aim RBC folate concentrations at > 400 ng/mL (906 nmol/L) in females of reproductive age to achieve the greatest reduction of neural tube defects at the population level. Consider using this threshold as an indicator of folate insufficiency in females of reproductive age. Use this threshold only at the population level as it cannot predict the individual risk of having a neural tube defect-affected pregnancy because low folate concentrations cannot explain all cases of neural tube defects. B Show 2 more Clinical findings Symptoms Past medical history Fecal incontinence Anorectal malformations Leg pain UTI Low back pain Neurological exam Urinary incontinence Urinary retention Lower limb paresis Weakness in the legs Integument exam Past obstetric history Fluid-filled sac on back maternal folic acid intake Sacral birthmark Sacral dimple Musculoskeletal exam Sacral tuft of hair https://web.pathway.md/diseases/recY3OoHHWCLfOthR 4/5 6/30/23, 1:06 AM Myelomeningocele Pathway Club foot Hip dislocation Kyphosis Scoliosis Lab findings Studies 1992 Hungarian Prenatal Vitamin Trial In women planning a pregnancy, vitamin supplementation was superior to trace-element supplementation with respect to congenital malformations. Czeizel AE et al. N Engl J Med. 1992 Dec 24. References 1. No authors listed. Practice Bulletin No. 187 Neural Tube Defects. Obstet Gynecol. 2017 Dec;130 6):e279- e290. Open 2. Mazzola CA, Assassi N, Baird LC et al. Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines for Pediatric Myelomeningocele: Executive Summary. Neurosurgery. 2019 Sep 1;85 3 299 301. Open 3. R Douglas Wilson, Tim Van Mieghem, Sylvie Langlois et al. Guideline No. 410 Prevention, Screening, Diagnosis, and Pregnancy Management for Fetal Neural Tube Defects. J Obstet Gynaecol Can. 2021 Jan;43 1 124 139.e8. Open 4. No authors listed. Committee Opinion No. 720 Maternal-Fetal Surgery for Myelomeningocele. Obstet Gynecol. 2017 Sep;130 3):e164-e167. Open 5. No authors listed. Guideline: optimal serum and red blood cell folate concentrations in women of reproductive age for prevention of neural tube defects. Geneva: World Health Organization; 2015. Open 6. Alan R Cohen, James Couto, James J Cummings et al. Position statement on fetal myelomeningocele repair. Am J Obstet Gynecol. 2014 Feb;210 2 107 11. Open https://web.pathway.md/diseases/recY3OoHHWCLfOthR 5/5