## **Core Concept**
The passage of gas through the gastrointestinal tract in a newborn can be an important indicator of certain conditions. The time it takes for gas to reach the colon can provide clues about the presence of intestinal obstruction or other gastrointestinal issues.

## **Why the Correct Answer is Right**
In a normal newborn, gas typically reaches the stomach within 30 minutes to 1 hour after birth and the small intestine within 1-2 hours. For gas to reach the colonic end, it usually takes around **6-8 hours** after birth in a healthy newborn. This timeframe can vary depending on factors like feeding (air swallowing during feeding) and the newborn's overall health.

## **Why Each Wrong Option is Incorrect**
- **Option A:** Less than 1 hour - This is too soon for gas to reach the colonic end; it typically reaches the stomach and small intestine within this timeframe but not the colon.
- **Option B:** 1-2 hours - At this point, gas usually reaches the small intestine but not typically the colon.
- **Option D:** More than 24 hours - This is too long; if gas hasn't reached the colon within this timeframe, it could indicate an obstruction.

## **Clinical Pearl / High-Yield Fact**
A useful clinical correlation is that in cases of intestinal obstruction, the absence of gas in the rectosigmoid area on an abdominal X-ray can be diagnostic. The timing of when gas reaches the colon can help differentiate between types of obstructions.

## **Correct Answer:** C. 6-8 hours.