What is the risk of recurrence of a neural tube defect (NTD) in a first-degree relative?

The recurrence risk of a neural tube defect (NTD) in a first-degree relative is indeed estimated to be between 2-5%. This risk is higher than the general population risk, which is approximately 0.1-0.3%, indicating that there is a familial component to the etiology of neural tube defects.

When assessing the risk for NTDs, it's important to consider both genetic and environmental factors, as studies have shown that having a sibling or a parent who has had an NTD increases the likelihood of having another affected child. The increase in risk is attributable to shared genetic predispositions, as well as potentially common environmental exposures.

This 2-5% figure reflects a consensus in genetic counseling literature, indicating an understanding of the multifactorial nature of NTDs. As a genetic counselor, being aware of these statistics aids in assessing family histories and informing patients of their recurrence risks, enabling them to make informed reproductive choices.