Prophylactic dose of folic acid in pregnancy is –
**Question:** Prophylactic dose of folic acid in pregnancy is -
A. 400 mcg daily
B. 5 mg daily
C. 5 mg daily
D. 1 mg daily
**Core Concept:**
Folic acid is a water-soluble vitamin of the B-complex group, which plays a crucial role in the synthesis of DNA, RNA, and hemoglobin. It is essential for the proper development of the central nervous system (CNS) and the red blood cells (RBCs) in the early stages of pregnancy. A deficiency of folic acid increases the risk of neural tube defects (NTDs) and megaloblastic anemia.
**Why the Correct Answer is Right:**
The correct answer is **400 mcg daily (0.4 mg)** because it is the recommended prophylactic dose of folic acid to reduce the risk of NTDs in pregnant women. This dose is effective in preventing most cases of NTDs, as well as maintaining normal RBC production.
**Why Each Wrong Option is Incorrect:**
A. 5 mg daily (0.5 mg) is too high for a prophylactic dose and may cause adverse effects like gastrointestinal distress and interference with vitamin B12 absorption.
B. 1 mg daily (1 mg) is also too high and may cause similar side effects.
C. 400 mcg daily (0.4 mg) is the correct prophylactic dose, as mentioned above.
**Why Each Wrong Option is Incorrect:**
A. 5 mg daily (0.5 mg) is too high for a prophylactic dose and may cause adverse effects like gastrointestinal distress and interference with vitamin B12 absorption.
B. 1 mg daily (1 mg) is also too high and may cause similar side effects.
C. 400 mcg daily (0.4 mg) is the correct prophylactic dose, as mentioned above.
**Clinical Pearls:**
1. **Prophylactic folic acid supplementation:** Folic acid supplementation during the preconception and early pregnancy period (up to 4 weeks) is crucial for preventing NTDs.
2. **NTDs prevention:** Neural tube defects occur in the first 28 days of pregnancy, which is why starting supplementation before conception is recommended.
3. **Vitamin B12 and folic acid interaction:** High doses of folic acid can interfere with vitamin B12 absorption, which is essential for proper myelination and neural tube development.
4. **Folic acid side effects:** Overdosing on folic acid can cause gastrointestinal upset, rash, and interference with vitamin B12 absorption.
**Answer:** A prophylactic dose of folic acid is 400 mcg daily (0.4 mg), which is the correct dose to prevent neural tube defects in pregnant women.