A full term baby, exclusively breast fed, at the end of 1 week was passing golden yellow stools and was found to have adequate hydration with normal systemic examination. The weight of the baby was just same as it was at bih. The pediatrician should now advise-

**Core Concept**
The baby in question is experiencing normal physiological adaptation to extrauterine life, characterized by the transition from meconium to bile-stained stools, known as **meconium transition**. This process is a result of the intestinal flora colonization and the maturation of the gastrointestinal system.

**Why the Correct Answer is Right**
During the first week of life, the gut is sterile, and meconium is passed. As the gut flora starts to colonize, the intestinal pH drops, and the bile salts in the gut start to break down the bilirubin, turning the stool from meconium to a golden yellow color. This process is a normal adaptation to extrauterine life and does not indicate any underlying pathology. The baby's adequate hydration and normal systemic examination suggest that the baby is not experiencing any significant gastrointestinal issues.

**Why Each Wrong Option is Incorrect**
**Option A:** This option may be tempting, but the baby's normal stool color and adequate hydration make it unlikely that the baby is experiencing diarrhea or dehydration. **Option B:** The baby's weight being the same as at birth is a normal finding in exclusively breastfed infants, especially during the first week of life. **Option C:** There is no indication of constipation or bowel obstruction, as the baby is passing stools and has a normal systemic examination.

**Clinical Pearl / High-Yield Fact**
In exclusively breastfed infants, a weight loss of up to 7-10% of birth weight is normal in the first week of life. This is due to the delay in the maturation of the gut and the transition from fetal to adult metabolism.

**Correct Answer:** D

✓ Correct Answer: D. Reassure the mother that nothing is abnormal