Mom is a 29-year-old woman with two normal children. The pregnancy was uneventful. Because of failure of labor to progress after 24 hours, a cesarean delivery was performed using general anesthesia. You are summoned by your emergency beeper and arrive 15 minutes later to the hospital obstetric operative delivery room. The father is in the delivery room looking pale and tearful.
On physical examination, Anita is 6 pounds, robust and has a vigorous cry, a good urine stream, spontaneous knee flexion and extension, and club feet. The delivery room nurses have applied a sterile dressing to Anita's back.
Known etiologies or associations of neural tube disorders include all of the following except
A. taking prenatal vitamins before conception
B. chromosomal disorders
C. maternal anticonvulsants
D. first-trimester hyperthermia
E. multiple malformation syndromes
The correct answer is A.
Prenatal vitamins do not cause spina bifida but are preventive for the disorder in a substantial number of individuals. Maternal anticonvulsants (eg, valproate), chromosomal disorders, first-trimester maternal hyperthermia, and Meckel syndrome (cleft, polydactyly, cystic liver and kidneys) are associated with spina bifida.
Question & Explanation: Daum RS, Canel JJ. McGraw-Hill Specialty Board Review: Pediatrics, 2e; 2011.