Unexpected changes in maternal breast size during pregnancy in relation to infant sex: An evolutionary interpretation

  title={Unexpected changes in maternal breast size during pregnancy in relation to infant sex: An evolutionary interpretation},
  author={Andrzej Galbarczyk},
  journal={American Journal of Human Biology},
  • A. Galbarczyk
  • Published 1 July 2011
  • Medicine
  • American Journal of Human Biology
Objectives: This study evaluated changes in breast size during pregnancy depending on infant sex. Due to larger nutritional needs during lactation, male infants may stimulate greater changes in maternal breast size than female infants. 
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Maternal serum HCG is higher in the presence of a female fetus as early as week 3 post-fertilization.
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Richer milk for sons but more milk for daughters: Sex‐biased investment during lactation varies with maternal life history in rhesus macaques
  • K. Hinde
  • Biology, Medicine
  • American journal of human biology : the official journal of the Human Biology Council
  • 2009
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