title: Second trimester amniotic fluid glucose, uric acid, phosphate, potassium, and sodium concentrations in relation to maternal pre-pregnancy BMI and birth weight centiles.
abstract: OBJECTIVE
  To study the evolution profile of amniotic fluid (AF) glucose, uric acid, phosphate, potassium, and sodium, in the second trimester of pregnancy, and explore the possible relations between the concentration of these components and maternal, as well as neonatal characteristics.
  
  
  METHODS
  AF of 52 pregnant women was analyzed using an automatic multichannel analyzer. Maternal age, pre-pregnancy Body Mass Index (BMI), inter-pregnancy intervals, and smoking status were derived from questionnaires. Information on pregnancy and delivery was collected from medical records.
  
  
  RESULTS
  Uric acid increased (r = 0.423, p < 0.01), while phosphate and glucose concentrations decreased during the period of 16-26th week of pregnancy (r = -0.590, p < 0.001 and r = -0.314, p < 0.05, respectively). Maternal pre-pregnancy BMI was significantly correlated with AF uric acid concentration (r = 0.460, p < 0.01) and marginally with AF glucose (r = 0.274, p = 0.052) and sodium (r = 0.254, p = 0.070) levels. Multiple linear regression indicated that mid-trimester AF uric acid and phosphate levels were significantly related to birth weight centiles (R(2)( )= 0.345, p < 0.05).
  
  
  CONCLUSIONS
  Our results suggest that: (a) AF phosphate levels reflect gestational age to a satisfactory extent, (b) maternal pre-pregnancy BMI is significantly correlated with AF uric acid concentration, and (c) in appropriate for gestational age infants, AF phosphate and uric acid levels may serve as potential biomarkers of birth weight centiles. Further studies on AF composition may help to unravel the biochemical pathways underlying fetal development and could offer insight on the potential impact of maternal nutritional management on fetal growth regulation.
authors.affiliation: Department of Food Science and Technology, School of Agriculture, Faculty of Agriculture, Forestry and Natural Environment, Aristotle University of Thessaloniki , Thessaloniki , Greece .
authors.forename: Maria
authors.initials: M
authors.lastname: Fotiou
authors.forename: Alexandra Maria
authors.initials: AM
authors.lastname: Michaelidou
authors.forename: Apostolos P
authors.initials: AP
authors.lastname: Athanasiadis
authors.forename: Georgios
authors.initials: G
authors.lastname: Menexes
authors.forename: Maria
authors.initials: M
authors.lastname: Symeonidou
authors.forename: Vasiliki
authors.initials: V
authors.lastname: Koulourida
authors.forename: Maria
authors.initials: M
authors.lastname: Ganidou
authors.forename: Theodoros D
authors.initials: TD
authors.lastname: Theodoridis
authors.forename: Basil C
authors.initials: BC
authors.lastname: Tarlatzis
mesh_terms: D000328:Adult; D000653:Amniotic Fluid / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D001724:Birth Weight; D015992:Body Mass Index; D005260:Female; D047109:Fetal Development / Q000502:physiology; D005865:Gestational Age; D005947:Glucose / Q000378:metabolism; D006801:Humans; D007231:Infant, Newborn; D016014:Linear Models; D008297:Male; D010710:Phosphates / Q000378:metabolism; D011188:Potassium / Q000378:metabolism; D011247:Pregnancy; D011262:Pregnancy Trimester, Second / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism; D014527:Uric Acid / Q000378:metabolism
chemical_list: D015415:Biomarkers; D010710:Phosphates; D014527:Uric Acid; D012964:Sodium; D005947:Glucose; D011188:Potassium
keywords: Amniotic fluid; glucose; maternal pre-pregnancy Body Mass Index; phosphate; pregnancy; uric acid