title: Recurrence of pre-eclampsia across generations: exploring fetal and maternal genetic components in a population based cohort.
abstract: OBJECTIVE
  To assess the impact on risk of pre-eclampsia of genes that work through the mother, and genes of paternal origin that work through the fetus.
  
  
  METHODS
  Population based cohort study.
  
  
  METHODS
  Registry data from Norway.
  
  
  METHODS
  Linked generational data from the medical birth registry of Norway (1967-2003): 438,597 mother-offspring units and 286,945 father-offspring units.
  
  
  METHODS
  Pre-eclampsia in the second generation.
  
  
  RESULTS
  The daughters of women who had pre-eclampsia during pregnancy had more than twice the risk of pre-eclampsia themselves (odds ratio 2.2, 95% confidence interval 2.0 to 2.4) compared with other women. Men born after a pregnancy complicated by pre-eclampsia had a moderately increased risk of fathering a pre-eclamptic pregnancy (1.5, 1.3 to 1.7). Sisters of affected men or women, who were themselves born after pregnancies not complicated by pre-eclampsia, also had an increased risk (2.0, 1.7 to 2.3). Women and men born after pre-eclamptic pregnancies were more likely to trigger severe pre-eclampsia in their own (or their partner's) pregnancy (3.0, 2.4 to 3.7, for mothers and 1.9, 1.4 to 2.5, for fathers).
  
  
  CONCLUSIONS
  Maternal genes and fetal genes from either the mother or father may trigger pre-eclampsia. The maternal association is stronger than the fetal association. The familial association predicts more severe pre-eclampsia.
authors.affiliation: Section for Epidemiology and Medical Statistics, Department of Public Health and Primary Health Care, University of Bergen, Norway. Rolv.Skjaerven@smis.uib.no
authors.forename: Rolv
authors.initials: R
authors.lastname: Skjaerven
authors.forename: Lars J
authors.initials: LJ
authors.lastname: Vatten
authors.forename: Allen J
authors.initials: AJ
authors.lastname: Wilcox
authors.forename: Thorbjørn
authors.initials: T
authors.lastname: Rønning
authors.forename: Lorentz M
authors.initials: LM
authors.lastname: Irgens
authors.forename: Rolv Terje
authors.initials: RT
authors.lastname: Lie
mesh_terms: D001722:Birth Order; D015331:Cohort Studies; D005191:Family Characteristics; D005220:Fathers; D005260:Female; D006801:Humans; D018445:Infectious Disease Transmission, Vertical; D008297:Male; D009035:Mothers; D009664:Norway / Q000453:epidemiology; D016017:Odds Ratio; D010375:Pedigree; D011225:Pre-Eclampsia / Q000453:epidemiology / Q000235:genetics*; D011247:Pregnancy; D012307:Risk Factors