title: [Very preterm birth: should we be interested in maternal pre-pregnancy body mass index?].
abstract: Link between maternal body mass index (BMI) and pregnancy outcome is not clear.
  
  
  OBJECTIVE
  To appreciate the impact of prepregnancy maternal BMI on very preterm birth (22-32 gestation's weeks).
  
  
  OBJECTIVE
  To assess how maternal BMI does explain the mechanism of very preterm birth among live births.
  
  
  METHODS
  Population-based study, including each mother with a live or stillborn baby was included in a geographically defined (Poitou-Charentes and Franche-comté, France) case-control study in 2004 to 2006. Leanness (BMI<18.5kg/m(2)) and overweight and obesity (BMI> or =25kg/m(2)) were defined according to World Health Organization's standards. Statistical analysis consisted in a polynomial regression on 832 mothers of very preterm babies and 431 mothers of full-term babies, taking account for confounders as maternal age, birth country, educational level, maternal work and smoking during the pregnancy.
  
  
  RESULTS
  Leanness is a risk factor for very preterm live birth (aOR=1.73 [1.12-2.68]), overweight is a risk factor for stillbirth. (aOR=1.71 [1.03-2.84]). Among mothers of live born babies, leanness is a risk factor for spontaneous preterm birth (aOR=2.12 [1.20-3.74]), whereas overweight is a risk factor for very preterm birth on medical decision due to gestational hypertension (aOR=2.85 [1.80-4.52]).
  
  
  CONCLUSIONS
  Morbid maternal stoutness before pregnancy is a complex risk factor for very preterm delivery. Women and couples should be informed and practitioners should be aware in order to prevent and manage this pathological status.
authors.affiliation: Réseau périnatal Franche-Comté, hôpital Saint-Jacques, CHU de Besançon, 25030 Besançon cedex, France. nafroukh@ch-valence.fr
authors.forename: N
authors.initials: N
authors.lastname: Hacini Afroukh
authors.forename: A
authors.initials: A
authors.lastname: Burguet
authors.forename: G
authors.initials: G
authors.lastname: Thiriez
authors.forename: B
authors.initials: B
authors.lastname: Mulin
authors.forename: M F
authors.initials: MF
authors.lastname: Bouthet
authors.forename: L
authors.initials: L
authors.lastname: Abraham
authors.forename: P
authors.initials: P
authors.lastname: Boisselier
authors.forename: P
authors.initials: P
authors.lastname: Villemonteix
authors.forename: V
authors.initials: V
authors.lastname: Bauer
authors.forename: J
authors.initials: J
authors.lastname: Lathelize
authors.forename: F
authors.initials: F
authors.lastname: Pierre
mesh_terms: D000293:Adolescent; D000328:Adult; D015992:Body Mass Index; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D009035:Mothers; D050177:Overweight / Q000150:complications; D011247:Pregnancy; D047928:Premature Birth; D012307:Risk Factors; D050497:Stillbirth; D013851:Thinness / Q000150:complications