US researchers have conducted a new study to try to understand why milk leaks from a mother's breast when she hears her baby crying.

NYU's findings could pave the way for a better understanding of the breastfeeding challenges for many women.


The scientists found that 30 seconds of constant crying of young mice triggered the release of oxytocin, the brain chemical that controls the mothers' breast milk release response. They also discovered the cerebral circuit that a newborn's crying stimulates to produce milk.

The study in mice gives new insights into the complex changes that occur in the brain during pregnancy and motherhood.

Habuon Issa, a graduate student at NYU Langon Health and co-author of the study, said: "Our findings reveal how a crying baby prepares his mother's brain to prepare her body for feeding. Without such preparation, there can be a delay of several minutes between feeding and milk flow."

The study showed that once the hormones were stimulated, the secretion continued to increase for about 5 minutes before declining, enabling the mothers of the mice to feed their young until they were full or started crying again.

The results showed that when an infant mouse starts crying, sound information travels to an area in its mother's brain called the nucleus within the posterior plates of the thalamus. This axon then sends signals to brain cells that release oxytocin in the hypothalamus.

Preventing milk waste

These neurons in the hypothalamus are "turned off" for the most part to prevent milk waste. However, after 30 seconds of constant crying, signals from the nucleus accumulated within the posterior plates of the thalamus and overcame the inhibitory mechanism, releasing oxytocin.

Professor Robert Frumke, from New York University Langone and co-author, said: "It's as if the brain wants to make sure that the infant is indeed there, that nutrition is really needed. There are specific brain circuits that suppress this process. Once it is confirmed that there is indeed a child, the brakes are released."

The benefits of breastfeeding for the baby

  • First milk (colostrum) helps a baby's digestive system function well, according to Sidra Medicine Qatar.
  • There are antibodies in breast milk that help the baby fight infection.
  • The nutrients in human breast milk are better for the baby than those in formula formulas.
  • Breastfeeding reduces the baby's risk of sudden infant death syndrome (SIDS).
  • Breast milk improves the baby's brain development.
  • A child is less likely to have certain health problems, such as childhood obesity, asthma or type II diabetes.

Benefits of breastfeeding for the mother

  • They help create a very special bond between the mother and her baby.
  • Convenient, breast milk is always available at the correct temperature and costs nothing.
  • It helps in burning calories, which helps the mother lose weight gained during pregnancy.
  • They help the uterus shrink to preconception size faster and slow down bleeding after childbirth.
  • Help lower a mother's risk of breast or ovarian cancer later in life.
  • Breastfeeding also helps lower the risk of diabetes later in life.
  • For mothers who already have diabetes, breastfeeding helps manage diabetes better and helps control blood sugar.

How long should breastfeeding take?

The World Health Organization recommends that babies be exclusively breastfed for the first six months of life, which means giving only breast milk and no other fluids (such as water, tea or juice) during this period.

After 6 months, it is recommended to provide age-appropriate complementary foods and continue breastfeeding, up to the age of two years.