**Core Concept:** Anencephaly is a severe neural tube defect (NTD) in early embryonic development, characterized by the absence of the brain and parts of the skull. In the context of this question, we are discussing the risk of recurrence in subsequent pregnancies.

**Why the Correct Answer is Right:** Anencephaly primarily results from genetic and environmental factors during early embryonic development, which makes it a non-recurrent disorder. Therefore, the correct answer is **D**: "The risk of recurrence is very low in subsequent pregnancies."

**Why Each Wrong Option is Incorrect:**

A. "Higher risk in first pregnancy" is incorrect because anencephaly is a sporadic event, meaning it is not expected to recur in the same individual.

B. "Risk remains constant throughout pregnancy" is incorrect because the risk is very low, not constant.

C. "Family history increases risk" is incorrect as anencephaly is primarily genetic in nature and not solely determined by family history.

**Clinical Pearl / High-Yield Fact:** A high-risk pregnancy factor associated with anencephaly is maternal exposure to folic acid deficiency during the preconception period and early pregnancy. This emphasizes the importance of folic acid supplementation before and during pregnancy.

**Correct Answer:** Risk of recurrence is very low in subsequent pregnancies (D).