title: Pre-pregnancy body mass index and gestational weight gain in Thai pregnant women as risks for low birth weight and macrosomia.
abstract: OBJECTIVE
  Maternal pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) have been reported to be associated with pregnancy outcomes. Due to the nutrition transition in Thailand, the double burden of malnutrition is increasing and this may have negative consequences on birth outcomes. This study aimed to investigate the relationship between pre-pregnancy BMI and GWG with the risks of low birth weight and macrosomia.
  
  
  METHODS
  We performed a secondary analysis of data obtained from an iodine supplementation trial in mildly iodine-deficient Thai pregnant women. Pre-pregnancy BMI was classified using the WHO classification. GWG was categorized using the IOM recommendation. Binary and multinomial logistic regressions were performed.
  
  
  RESULTS
  Among 378 pregnant women, the prevalence of pre-pregnancy underweight (BMI<18.5 kg/m2) and overweight (BMI>=25 kg/m2) were 17.2% and 14.3%, respectively. Normal weight women had the highest median GWG [15.0 (12.0, 19.0) kg] when compared to overweight women [13.2 (9.0, 16.3) kg]. Forty-one percent of women had excessive GWG, while 23% of women gained weight inadequately. Women with a high pre-pregnancy BMI had a 7-fold higher risk of having a macrosomic infant. Women who had excessive GWG were 8 times more likely to deliver a newborn with macrosomia.
  
  
  CONCLUSIONS
  Both high pre-pregnancy maternal weight and excessive weight gain during pregnancy increase risk of infant macrosomia. Therefore, maintaining normal body weight before and throughout pregnancy should be recommended in order to reduce the risk of excessive infant birth weight and its associated complications.
authors.affiliation: Institute of Nutrition, Mahidol University, Nakhon Pathom, Thailand. Email: tippawan.pon@mahidol.ac.th; tpongch@gmail.com.
authors.forename: Tippawan
authors.initials: T
authors.lastname: Pongcharoen
authors.affiliation: Institute of Nutrition, Mahidol University, Nakhon Pathom, Thailand.|Division of Human Nutrition, Wageningen University, Wageningen, the Netherlands.
authors.forename: Sueppong
authors.initials: S
authors.lastname: Gowachirapant
authors.affiliation: Institute of Nutrition, Mahidol University, Nakhon Pathom, Thailand.
authors.forename: Purisa
authors.initials: P
authors.lastname: Wecharak
authors.affiliation: Institute of Nutrition, Mahidol University, Nakhon Pathom, Thailand.
authors.forename: Natnaree
authors.initials: N
authors.lastname: Sangket
authors.affiliation: Institute of Nutrition, Mahidol University, Nakhon Pathom, Thailand.
authors.forename: Pattanee
authors.initials: P
authors.lastname: Winichagoon
mesh_terms: D000293:Adolescent; D000328:Adult; D015992:Body Mass Index; D005260:Female; D005320:Fetal Macrosomia / Q000453:epidemiology*; D005865:Gestational Age; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D050177:Overweight / Q000453:epidemiology; D016742:Preconception Care; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology; D012307:Risk Factors; D013785:Thailand / Q000453:epidemiology; D013851:Thinness / Q000453:epidemiology; D015430:Weight Gain; D055815:Young Adult