Production of breastmilk and its let down during breastfeeding is a complex process. It includes active involvement of baby and mother. The physical and chemical integration results in satisfaction and benefits for both, the mom as well as the baby.
Breastmilk production and let down in a lactating mom are strongly related to the mum’s body response to sensory stimuli provided by the suckling baby and hormonal changes taking place in her body.The process can be roughly divided in to two phases:

A suckling baby massages the nipple with his tongue and stimulates the sensory nerve endings in the nipple and
areola.The stimuli are transmitted to the mother’s pituitary gland. The pituitary releases prolactin, a hormone responsible for milk production in alveoli. The more you breastfeed, the higher the prolactin level and higher is breastmilk production.
Breastfeeding also triggers the release of oxytocin – another hormone responsible for lactation. It stimulates contraction of the cells and milk ejection. Babies younger than 3 months usually are not able to control the let down rate of breastmilk. A baby can achieve control of breastmilk let down by adjusting the suckling force only after 3 months.

This phase of breastfeeding is intense, active work of lip and tongue muscles. The baby works hard to get breastmilk which slowly becomes thicker, more nutritious, filling and calorie rich – it satisfies hunger.
Nipple length is almost doubled during suction and then it shrinks again during swallowing. The baby’s tongue presses it into the hard palate, and causes milk let down. Lips press against the areola so that vacuum is created in the baby’s mouth, facilitating breastmilk flow into the oral cavity. Soft palate is raised, epiglottis closes the entrance to the larynx and breastmilk flows into the digestive tract. Then the epiglottis opens, the soft palate is lowered and the baby exhales.

Suckling during breastfeeding in babies is very different from suckling in adults. Anatomy of the baby’s mouth allows for inhalation, a few suckling movements, swallowing and exhalation (the baby does not breathe after each suckling sequence). This way the baby can drink without the risk of choking – the respiratory and digestive tracts are not open at the same time.

One of the most important things while breastfeeding is to make sure your baby is breathing freely through the nose. When he has a runny nose, suck out the secretion before feeding.