Breast nonmalignant
Neonatal breast

Topic Completed: 1 May 2014

Minor changes: 3 September 2019

Copyright: 2002-2019,, Inc.

PubMed Search: Neonatal breast [title]

Belinda Lategan, M.D.
Page views in 2019: 95
Page views in 2020 to date: 38
Cite this page: Lategan B Neonatal breast. website. Accessed May 27th, 2020.
Definition / general
  • Identical in males and females at birth
  • Nipple is small pit in center of thickened areola, becomes everted shortly after birth due to proliferation of mesenchyme underlying the areola
  • Breast enlargement (uni or bilateral) is present in up to 70% of neonates due to neonatal prolactin production, caused by falling levels of maternal estrogens; associated with production of "witch's milk" in males and females
  • Continued breast stimulation (squeezing or massaging breasts) may cause hypersecretory state to persist
  • Milk secretion: resembles colostrum; contains water, fat and cellular debris
Microscopic (histologic) description
  • Duct dilation without acini
Microscopic (histologic) images

AFIP images

Neonatal breast ectasia with dilation of mammary ducts

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