What are the reasons for a 4-month-old baby frequently sucking their hands?

Frequent hand-sucking in a 4-month-old baby may be caused by the need for comfort and security, the oral stage of development, food stagnation (indigestion), gastroesophageal reflux, or oral thrush. If any abnormalities are observed, it is recommended to seek medical advice promptly. The specific causes are analyzed as follows:

1. Comfort and Sense of Security

After birth, babies feel safe when sucking on the nipple or being gently touched. When separated from their mother or feeling anxious, babies may suck their hands to comfort themselves and relieve stress. Parents can spend more time with the baby, offering sufficient affection and reassurance. Pacifiers or teething toys may also be used to gradually help the baby overcome the habit of hand-sucking.

2. Oral Stage

At four months old, babies are in the oral developmental stage, during which they use their mouths to perceive and explore the surrounding world. Since their hands are the most accessible and controllable part of their body, babies often put them into their mouths to sense their shape and size with their lips and tongue. No special intervention is needed; parents should simply keep the baby’s hands clean and hygienic to prevent bacterial entry into the mouth.

3. Food Stagnation (Indigestion)

Digestive discomfort and increased anxiety due to indigestion may lead babies to suck their hands for comfort. Parents should pay attention to regulating the baby's diet, avoiding overfeeding and foods that are difficult to digest.

4. Gastroesophageal Reflux

Improper feeding posture may trigger gastroesophageal reflux, causing discomfort such as nausea. Since babies cannot express their feelings verbally, they may resort to hand-sucking for psychological comfort and physical relief. Symptoms may include bloating, vomiting, and persistent crying. It is recommended that parents adjust feeding positions and adopt a feeding schedule of small, frequent meals.

5. Oral Thrush

Oral thrush, caused by Candida albicans infection in the mouth, can lead to oral pain, prompting the baby to suck their hands in an attempt to soothe discomfort. White patches or ulcers may be visible inside the mouth, and the baby may refuse to eat and cry frequently. Treatment should follow medical advice and may include medications such as clotrimazole capsules, amoxicillin granules, or nystatin tablets.

Parents are advised to closely monitor the baby’s condition, especially oral hygiene, and clean nipples and bottle nipples before and after feeding. Feeding should be done in small, frequent portions to avoid overfeeding.