title: Study of the prognostic value of the pregnant nutrition graph (Vallop Curve) to predict the incidence of low birth weight infants.
abstract: OBJECTIVE
  To test the prognostic value of the pregnant nutrition graph (Vallop Curve).
  
  
  METHODS
  Prospective and comparative study.
  
  
  METHODS
  Department of Obstetrics and Gynecology, Prangnangklao Hospital.
  
  
  METHODS
  510 cases who attended the antenatal care clinic and delivered at Prangnangklao Hospital from January 2004 to July 2004.
  
  
  METHODS
  Height, weight and pre-pregnancy body mass index (BMI) of the women were recorded and classified BMI of each into 3 groups, low BMI (< 19.8) normal BMI (19.8 - 26.0) and high BMI (26.1 - 29.0.) The weight of the pregnant women in each gestational week was calculated as percentage of standard BMI at 21 and plotted in a Vallop Curve. The data was analyzed by using an Anova Test and Wilson Method to find association. A p-value of < 0.05 was regarded as significant. OUTCOME EVALUATION: Birth weight curve, below the 2,500 gm line and above the 2,500 gm line.
  
  
  RESULTS
  The mean birth weight of low BMI was 2,541.70 +/- 276.89 gm. The mean birth weight of normal BMI was 3,021.30 +/- 318.61 gm. The mean birth weight of high BMI was 3,520.00 +/- 250.65 gm. There was a significant difference in weight by the Anova Test. Sensitivity was 65.6%. Specificity was 87.4%. Positive predictive value was 42.9%. Negative predictive value was 94.7%. P-value was < 0.001 at 95% confident interval by the Wilson Method.
  
  
  CONCLUSIONS
  The Vallop Curve may be useful to predict the incidence low birth weight infants, but in the future the Vallop Curve may be changed corresponding to change of socio-economic status and also to simplify it's method of usage.
authors.affiliation: Department of Obstetrics and Gynecology, Pranangkloa Hospital, Nonthaburi 11000, Thailand.
authors.forename: Anurach
authors.initials: A
authors.lastname: Kulvanitchaiyanunt
mesh_terms: D000328:Adult; D015992:Body Mass Index; D003906:Developing Countries; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D015596:Nutrition Assessment; D011237:Predictive Value of Tests; D011247:Pregnancy; D011379:Prognosis; D011446:Prospective Studies; D013785:Thailand