title: The risk factors of low birth weight infants in the northern part of Thailand.
abstract: BACKGROUND
  The incidence of low birth weight (LBW) in Chiang Mai University Hospital was high.
  
  
  OBJECTIVE
  Determined the incidence and risk factors of low birth weight infants.
  
  
  METHODS
  The present study included pregnant women between 1989 and 1990 who attended the antenatal clinics (ANC) having a gestational age less than or equal to 24 weeks. During that period, up to delivery, clinical and other potential data namely demographic and biomedical factors, maternal status, socioeconomic factors, and nutritional factors were included. The birth weight at birth less than 2,500 gm was considered LBW.
  
  
  RESULTS
  Two thousand one hundred eighty four pregnant subjects who delivered live born and were still eligible, were used for analysis in the present study. The incidence of LBW was 9.2% (201/2,184). Women with body mass index (BMI) at first antenatal clinics (ANC) less than 18.5 Kg/m2 and weight gain during the second trimester less than 300 grams/week was the strongest independent risk factor for LBW (odds ratio 11.25, 95% confidence interval (CI) 5.77-21.94). The number of antenatal care less than 4, monilial vaginitis, the infestation of hookworm and strongyloides, and pregnancy-induced hypertension were independent risk factors (odds ratio 11.04, 3.14, 4.93 and 4.02 respectively).
  
  
  CONCLUSIONS
  The present study showed that low initial BMI, low weight gain in the second trimester, and low attendance at ANC are associated to the occurrence of LBW. The development of a scoring system for detecting high-risk of LBW in pregnant women based on a combination of antenatal factors should be pursued.
authors.forename: Ampica
authors.initials: A
authors.lastname: Mangklabruks
authors.forename: Amaraporn
authors.initials: A
authors.lastname: Rerkasem
authors.forename: Antika
authors.initials: A
authors.lastname: Wongthanee
authors.forename: Kittipan
authors.initials: K
authors.lastname: Rerkasem
authors.forename: Pien
authors.initials: P
authors.lastname: Chiowanich
authors.forename: Piyamitr
authors.initials: P
authors.lastname: Sritara
authors.forename: Sakda
authors.initials: S
authors.lastname: Pruenglampoo
authors.forename: Tada
authors.initials: T
authors.lastname: Yipintsoi
authors.forename: Theera
authors.initials: T
authors.lastname: Tongsong
authors.forename: Tom
authors.initials: T
authors.lastname: Marshall
authors.forename: Watcharee
authors.initials: W
authors.lastname: Tantiprabha
mesh_terms: D000293:Adolescent; D000328:Adult; D015992:Body Mass Index; D005260:Female; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D008297:Male; D015999:Multivariate Analysis; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011295:Prenatal Care / Q000706:statistics & numerical data; D012307:Risk Factors; D013785:Thailand / Q000453:epidemiology; D015430:Weight Gain; D055815:Young Adult