A mother with 10 weeks pregnancy and who had previously delivered a baby with open neural tube defect which statement is true :
**Core Concept**
The question is testing the understanding of the relationship between a previous pregnancy with open neural tube defect (ONTD) and the risk of recurrence in a subsequent pregnancy. This is relevant to the diagnosis and management of neural tube defects, which are congenital anomalies of the central nervous system.
**Why the Correct Answer is Right**
The mother's previous pregnancy with ONTD indicates a higher risk of recurrence in the current pregnancy. This is because the risk of recurrence of ONTD is significantly increased in families with a history of previous affected pregnancies. The exact mechanism is not fully understood, but it is believed to be related to genetic factors, including mutations in genes involved in neural tube closure, such as MTHFR. The risk of recurrence is estimated to be around 3-5% without any intervention, making folic acid supplementation a crucial preventive measure.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not address the relationship between the mother's previous pregnancy with ONTD and the risk of recurrence in the current pregnancy.
**Option B:** This option is incorrect because it does not provide any relevant information about the risk of recurrence of ONTD in the mother's current pregnancy.
**Option C:** This option is incorrect because it is not a relevant statement regarding the risk of recurrence of ONTD in the mother's current pregnancy.
**Clinical Pearl / High-Yield Fact**
Folic acid supplementation is essential in preventing neural tube defects, especially in women with a history of previous affected pregnancies. A daily dose of 4 mg of folic acid is recommended for women who have had a previous pregnancy with ONTD, starting at least 1 month before conception and continuing through the first trimester.
**Correct Answer:** C.