A common newborn procedure faces new scrutiny as evidence undercuts one widely blamed cause of breastfeeding trouble

A joint study by the University of Oulu and Oulu University Hospital suggests that a newborn's upper lip frenulum is unlikely to be a major cause of breastfeeding difficulties.

The study, published in JAMA Network Open, followed 264 mother–infant pairs at Oulu University Hospital between 2023 and 2024.

Researchers assessed the anatomy and mobility of the upper lip frenulum in healthy, full-term infants and compared the findings with mothers' reported breastfeeding experiences. ...