My baby is now almost 5 months old, and she grunts a lot while nursing. She did not grunt when she was younger - this started approximately at 3.5 months, and continues since then. She grants and moans usually only during day time feedings. Sometimes it's accompanied by pulling her legs and a fart or a poop at the end but not always. The sounds that she is making are pretty loud and to me look like sounds of pain or discomfort rather than sound of pleasure. Sometimes she even can pull away and cry or whine a little.
From what I read I have two possible explanations - first, could be gas/digestion discomfort, and second, could be teething pain. If this is gas/digestion related then why does it happen only when she is nursing? She does not grunt at other times - either awake or asleep. Also, she does not seem to be a very gassy baby but granting is pretty regular - few times a day. Teething pain could be another explanation but she does not have any sign of teeth yet (visually) and also does not drool excessively. She likes to chew on her teethers and tries to put everything into her mouth.
I asked our pediatrician at our 4-month appointment, and she just said that it was nothing to be concerned about if the baby is gaining weight and overall looks healthy. I still have some doubts - it's stresses me out when I hear these sounds. I tried to search forum for this topic but all old threads were about grunting at earlier age (first weeks or a couple months) and mostly at night/ in sleep. Anyone experienced what we have?