It is not uncommon for babies to experience changes in their bowel movements as they grow. The color and consistency of their poop can vary depending on various factors such as diet, digestion, and hydration levels. In the case of your 16-week-old baby having smelly and dark green poop with a clay-like texture, there could be several possible explanations.
One possibility is that your baby's diet has changed recently. If you have introduced new foods or started giving them formula instead of breast milk, these dietary changes can affect the color and odor of their stool.
Another factor to consider is dehydration. If your baby is not getting enough fluids or if they are experiencing mild dehydration due to hot weather or illness, it can result in darker and more concentrated urine which may affect the color of their poop.
However, if your baby's behavior remains normal with no signs of distress such as fever or vomiting, it is likely that these changes in their bowel movements are within the range of normal variation. As long as your baby continues to eat well, gain weight appropriately, and does not show any other concerning symptoms, there may not be an immediate need for alarm.
That being said, if you are still worried or if these changes persist for an extended period of time (more than a few days), it would be a good idea to consult your pediatrician. They can provide you with personalized advice and guidance based on your baby's specific situation.
In general, it is always better to err on the side of caution when it comes to your baby's health. If you have any concerns or if you notice any significant changes in their behavior or overall well-being, do not hesitate to reach out to your healthcare provider for professional evaluation and reassurance.