title: Hyperemesis gravidarum and long-term mortality: a population-based cohort study.
abstract: OBJECTIVE
  To investigate whether exposure to hyperemesis gravidarum (HG) is associated with increased maternal long-term mortality.
  
  
  METHODS
  Population-based cohort study.
  
  
  METHODS
  Medical Birth Registry of Norway (1967-2002) linked to the Cause of Death Registry.
  
  
  METHODS
  Women in Norway with singleton births in the period 1967-2002, with and without HG. Women were followed until 2009 or death.
  
  
  METHODS
  Cox proportional hazard regression model was applied to estimate hazard ratios (HRs) with 95% confidence interval (CI).
  
  
  METHODS
  The primary outcome was all-cause mortality during follow up. Secondary outcomes were cause-specific mortality (cardiovascular mortality, deaths due to cancer, external causes or mental and behavioural disorders).
  
  
  RESULTS
  Of 999 161 women with singleton births, 13 397 (1.3%) experienced HG. During a median follow up of 26 years (25 902 036 person-years), 43 470 women died (4.4%). Women exposed to HG had a lower risk of long-term all-cause mortality compared with women without HG (crude HR 0.82; 95% CI 0.75-0.90). When adjusting for confounders, this reduction was no longer significant (adjusted HR 0.92; 95% CI 0.84-1.01). Women exposed to HG had a similar risk of cardiovascular death as women not exposed (adjusted HR 1.04; 95% CI 0.83-1.29), but a lower long-term risk of death from cancer (adjusted HR 0.86; 95% CI 0.75-0.98).
  
  
  CONCLUSIONS
  In this large population-based cohort study, HG was not associated with an increased risk of long-term all-cause mortality. Women exposed to HG had no increase in mortality due to cardiovascular disease, but had a reduced risk of death from cancer.
  
  
  CONCLUSIONS
  Population-based cohort study: Hyperemesis was not associated with an increased risk of long-term mortality.
authors.affiliation: Department of Cardiology, Oslo University Hospital Ulleval, Oslo, Norway.|Epidemiological Division, National Institute of Public Health, Oslo, Norway.
authors.forename: S
authors.initials: S
authors.lastname: Fossum
authors.affiliation: The Intervention Center, Oslo University Hospital, Oslo, Norway.
authors.forename: Å V
authors.initials: ÅV
authors.lastname: Vikanes
authors.affiliation: University of Oslo, Oslo, Norway.|Epidemiological Division, National Institute of Public Health, Oslo, Norway.
authors.forename: Ø
authors.initials: Ø
authors.lastname: Naess
authors.affiliation: Cancer Registry of Norway, Oslo, Norway.
authors.forename: L
authors.initials: L
authors.lastname: Vos
authors.affiliation: Cancer Registry of Norway, Oslo, Norway.
authors.forename: T
authors.initials: T
authors.lastname: Grotmol
authors.affiliation: Department of Cardiology, Oslo University Hospital Ulleval, Oslo, Norway.|University of Oslo, Oslo, Norway.
authors.forename: S
authors.initials: S
authors.lastname: Halvorsen
mesh_terms: D000328:Adult; D002423:Cause of Death; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006939:Hyperemesis Gravidarum / Q000401:mortality*; D008428:Maternal Mortality; D009664:Norway; D011247:Pregnancy; D016016:Proportional Hazards Models; D012042:Registries; D012307:Risk Factors; D016019:Survival Analysis; D055815:Young Adult
keywords: Cancer; cardiovascular disease; cohort study; hyperemesis gravidarum; long-term mortality