## **Core Concept**
Delayed cord clamping (DCC) is a practice that involves waiting for at least 30 seconds to 1 minute before clamping the umbilical cord after birth. This allows for the transfer of blood from the placenta to the newborn, increasing the newborn's blood volume and potentially reducing the risk of anemia.

## **Why the Correct Answer is Right**
The correct answer of 30% is based on studies that have shown that approximately 30% of placental blood volume is transferred to the newborn during delayed cord clamping. This transfer of blood is mediated by the **uteroplacental circulation**, which continues to perfuse the placenta after birth, and **fetal circulation**, which gradually increases its pressure to take over the circulation. The amount of blood transferred can vary depending on factors such as cord length and the timing of cord clamping.

## **Why Each Wrong Option is Incorrect**
- **Option A:** 10% - This is too low, as studies suggest a more significant transfer of blood occurs with delayed cord clamping.
- **Option B:** 20% - While closer, this still underestimates the amount of blood transferred to the newborn.
- **Option D:** 40% - This overestimates the typical amount of blood transferred during delayed cord clamping.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that delayed cord clamping for at least 30 seconds to 1 minute can significantly increase the newborn's blood volume by approximately 30%, which may help reduce the risk of **neonatal anemia** and improve **circulatory stability**. This practice is recommended by various neonatal and obstetric guidelines.

## **Correct Answer:** C. 30%