title: Do normal-weight women pregnant with twins are at the lowest risk of developing preeclampsia?
abstract: OBJECTIVE
  To determine the relation between preeclampsia (PE) and pregravid body mass index (BMI) in twin pregnancy.
  
  
  METHODS
  Retrospective cohort study of 542 women pregnant with twins.
  
  
  RESULTS
  Forty-nine patients developed PE (9%). Underweight, overweight and obese women were at a higher risk of PE than normal-weight mothers. There was no linear (p = 0.7) but significant U-shaped relation between BMI and PE (p < 0.006). The lowest risk of PE development was related to BMI of about 23 kg/m2.
  
  
  CONCLUSIONS
  Nonlinear relation between PE occurrence and BMI suggests that using homogeneous PE risks of BMI groups may be incorrect.
authors.affiliation: a 1st Department of Obstetrics and Gynecology , Medical University of Warsaw , Starynkiewicza Square 1/3, Warsaw , Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Kosinska-Kaczynska
authors.affiliation: a 1st Department of Obstetrics and Gynecology , Medical University of Warsaw , Starynkiewicza Square 1/3, Warsaw , Poland.
authors.forename: Miroslaw
authors.initials: M
authors.lastname: Wielgos
mesh_terms: D000328:Adult; D015992:Body Mass Index; D001835:Body Weight; D005260:Female; D006801:Humans; D050177:Overweight / Q000150:complications; D011225:Pre-Eclampsia / Q000175:diagnosis / Q000209:etiology*; D011247:Pregnancy; D059285:Pregnancy, Twin; D012189:Retrospective Studies; D012307:Risk Factors; D013851:Thinness / Q000150:complications
keywords: Body mass index; hypertension; multiple pregnancy; obesity; overweight; pregravid weight; proteinuria