Close up, baby drinking at mother's breast

Study Summary

Ultrasound Imaging Study of the Mechanics of Breastfeeding 


Imaging Evaluation of the Human Nipple During Breast-Feeding

Wilbur L. Smith, MD; Allen Erenberg, MD; Arthur Nowak, DMD

American Journal of Diseases of Children, 1988

A 1988 U.S. study used real-time ultrasound imaging to document and describe the mechanics and characteristics of the human nipple during breastfeeding.

Background

The ability to feed orally is critical for the survival of infants. Breastfeeding, of course, is the most natural way for infants to feed. Doctors and professional medical associations also agree that breast milk is best for babies. Still, the exact mechanism of breastfeeding is not completely understood. In what is believed to be the first study of its kind, the authors used in-vivo ultrasound imaging to quantify the physical behaviour of the nipple and describe the mechanism of normal sucking.

Methods

The authors used a high-resolution real-time ultrasound technique to study breastfeeding in 16 infants. The infants were from 60 to 120 days old and all were primarily breastfed though some received supplemental bottle feedings. The study commenced at the beginning of breast feeding and continued until ultrasound visual monitoring indicated that the milk intake slowed. Feeding from both breasts was monitored.

Imaging was performed using a mechanical real-time ultrasound device and data was recorded on video tape. Data was analysed from a high-resolution monitor using a video tape deck with single frame and stop frame capabilities.

Hand callipers were used to take measurements from the display. Independent measurements by all of the authors agreed to within 1mm. Measurements were obtained for elongation, compression and widening of the nipple. 

Results

  • Changes in nipple dimensions during sucking were similar throughout the study group. 
  • Data shows that the human nipple is highly elastic and can stretch to twice its normal length. 
  • Data reinforces the concept that the infant’s cheeks act mainly to form a passive seal. 
  • The nipple is compressed to half its height between the tongue and palate. 
  • “It is important to note that milk ejection occurs after maximum compression.” 
  • Infants seem to rely less on the undulating motion of the tongue and more on an up and down movement of the jaw, tongue and hyoid. 
  • “This suggests that the jaw actually creates a negative pressure by enlarging the oral cavity to induce milk ejection. 
  • “The human nipple and infant sucking mechanisms are well adapted for nutrient intake.” 
  • Data suggests that nipple compression may draw milk into the ducts and the actual release of the milk is stimulated by a vacuum caused by the rapid enlargement of the oral cavity. 
  • “The undulant tongue motions may have less to do with milk expression than previously suspected.”

MAM Service

You can find the complete article at: mambaby.com/professionals