The WHNP is seeing a pregnant patient, at 13 weeks gestation…

The WHNP is seeing a pregnant patient, at 13 weeks gestation (G2, A0, P0, T1), with her second pregnancy. The patient is anxious because her first born child had spina bifida (a neural tube defect or NTD) and the patient expresses concern that her baby she is carrying will also have the condition.  The WHNP knows that that neural tube defects: