title: The effect of advanced maternal age upon human milk fat content.
abstract: BACKGROUND
  Little is known about the effect of maternal age on human milk (HM) composition. This study was designed to study fat content, estimated by creamatocrit (CMT), in HM collected in the first 2 weeks of life in older (≥ 35 years) compared with younger (<35 years) mothers.
  
  
  METHODS
  Ninety lactating mothers (48 older, 42 younger) of newborns were recruited within the first 3 days of delivery. CMTs were measured at 72 hours, 7 days, and 14 days after delivery for HM in a capillary tube after centrifugation at 5,366 g for 5 minutes.
  
  
  RESULTS
  The groups did not differ in terms of maternal height and diet, infant birth weight, gestational age (GA), or pregnancy weight gain. They differed significantly in terms of maternal age and parity. Mean colostrum CMT was significantly higher in the group of older mothers. Colostrum CMT correlated positively with maternal age (R(2)=0.11, p=0.006) and inversely with GA (R(2)=0.1, p=0.03) but did not relate with either maternal weight or body mass index. CMT at age 7 days and 2 weeks was not affected by maternal age or GA. In multivariate regression analysis colostrum CMT correlated significantly only with maternal age and GA (R(2)=0.3, p<0.001).
  
  
  CONCLUSIONS
  Colostrum fat content of older mothers is much higher than that of younger mothers and inversely related with GA at delivery. This increase in colostrum fat content obtained from mothers with advanced age may be due to increased fat synthesis and excretion in milk, reduced water content of milk, or a combination of both.
authors.affiliation: Department of Neonatology, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.
authors.forename: Moran
authors.initials: M
authors.lastname: Hausman Kedem
authors.forename: Dror
authors.initials: D
authors.lastname: Mandel
authors.forename: Keren Armoni
authors.initials: KA
authors.lastname: Domani
authors.forename: Francis B
authors.initials: FB
authors.lastname: Mimouni
authors.forename: Vered
authors.initials: V
authors.lastname: Shay
authors.forename: Ronella
authors.initials: R
authors.lastname: Marom
authors.forename: Shaul
authors.initials: S
authors.lastname: Dollberg
authors.forename: Lea
authors.initials: L
authors.lastname: Herman
authors.forename: Ronit
authors.initials: R
authors.lastname: Lubetzky
mesh_terms: D000328:Adult; D003126:Colostrum / Q000737:chemistry / Q000378:metabolism*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007774:Lactation / Q000502:physiology*; D050356:Lipid Metabolism / Q000502:physiology*; D008423:Maternal Age; D039382:Maternal Nutritional Physiological Phenomena; D008875:Middle Aged; D008895:Milk, Human / Q000737:chemistry / Q000378:metabolism*; D011247:Pregnancy; D011446:Prospective Studies; D015203:Reproducibility of Results