Registered Nurse Certified in Maternal Newborn Nursing (RNC-MNN) Practice Test

When do most newborns pass their first meconium stool?

1. Within 2 hours

2. Within 12 hours

3. Within 24 hours

4. Within 48 hours

The correct answer is: Within 24 hours

Most newborns typically pass their first meconium stool within the first 24 hours after birth. Meconium is a thick, dark green substance that consists of what the fetus ingested while in the womb, including amniotic fluid, lanugo, and other cellular debris. The timing of meconium passage is an important indicator of a newborn's health and gastrointestinal function. Passing meconium within the first 24 hours is considered normal, as it indicates a functioning digestive system and a lack of intestinal obstruction. If a newborn has not passed meconium within this timeframe, it may raise concerns about potential issues such as meconium ileus or other gastrointestinal anomalies. In contrast, while many newborns may pass meconium sooner than 24 hours—some even within the first few hours—this is not the expected timeframe for all infants. Thus, 24 hours is often used as the benchmark for when to expect the first meconium passage in a healthy newborn.