Check out this answer from Consensus:
Baby hiccups can be caused by esophageal irritation due to regurgitated gastric fluids and curdled milk particles. Additionally, hiccups may have a physiological role during fetal development, particularly in the maturation of the respiratory system. Understanding these causes can help in managing hiccups more effectively and alleviating parental concerns.
Hiccups are a common phenomenon in infants, often causing concern among new parents. Understanding the underlying causes can help in managing and possibly preventing these episodes. This article explores the primary reasons behind baby hiccups based on recent research findings.
Esophageal Irritation
One of the primary causes of hiccups in infants is irritation of the esophagus. Research has shown that this irritation can be triggered by gastric fluids that regurgitate into the esophagus after nursing. This regurgitation can occur without visible vomiting, making it less noticeable to caregivers. The presence of curdled milk particles can exacerbate this irritation, leading to hiccups1.
Key Points:
- Regurgitation: Gastric fluids moving up the esophagus can irritate it, causing hiccups.
- Curdled Milk: Particles of curdled milk can increase the irritation.
- Invisibility: Regurgitation may not always be visible, as fluids might not leave the mouth.
Physiological Mechanisms
Hiccups are not just a postnatal phenomenon; they are also common during fetal development. A study on preterm infants has provided insights into the physiological aspects of hiccups. It was observed that hiccups often occur during the expiratory phase of breathing and are associated with a shorter inspiratory time and a larger tidal volume compared to spontaneous breaths. This suggests that hiccups might play a role in the development of the respiratory system in fetuses and preterm infants2.
Key Points:
- Expiratory Phase: Hiccups typically occur during the expiratory phase of breathing.
- Tidal Volume: Hiccups are associated with a larger tidal volume.
- Respiratory Development: Hiccups may have a physiological role in the development of the respiratory system.