title: Fertility treatment and risk of childhood and adolescent mental disorders: register based cohort study.
abstract: OBJECTIVE
  To assess the mental health of children born after fertility treatment by comparing their risk of mental disorders with that of spontaneously conceived children.
  
  
  METHODS
  Prospective register based cohort study.
  
  
  METHODS
  Nationwide register based information from Danish National Health Registers cross linked by a unique personal identification number assigned to all citizens in Denmark.
  
  
  METHODS
  All children born in Denmark in 1995-2003 with follow-up in 2012 when the children were aged 8-17; 33,139 children were conceived after fertility treatment and 555,828 children were born after spontaneous conception.
  
  
  METHODS
  Absolute risks and hazard ratios for overall and specific mental disorders estimated with adjustment for potential confounding variables. Estimated association between the risk of mental disorders and subtypes of procedures, hormone treatments, gamete types, and cause of infertility.
  
  
  RESULTS
  The risk of mental disorders in children born after in vitro fertilisation or intracytoplasmic sperm injection was low, and was no higher than in spontaneously conceived children, except for a borderline significant increased risk of tic disorders (hazard ratio 1.40, 95% confidence interval 1.01 to 1.95; absolute risk 0.3%). In contrast, children born after ovulation induction with or without insemination had low but significantly increased risks of any mental disorder (1.20, 1.11 to 1.31; absolute risk 4.1%), autism spectrum disorders (1.20, 1.05 to 1.37; 1.5%), hyperkinetic disorders (1.23, 1.08 to 1.40; 1.7%), conduct, emotional, or social disorder (1.21, 1.02 to 1.45; 0.8%), and tic disorders (1.51, 1.16 to 1.96; 0.4%). There was no risk systematically related to any specific type of hormone drug treatment.
  
  
  CONCLUSIONS
  There was a small increase in the incidence of mental disorders in children born after ovulation induction/intrauterine insemination. Children born after in vitro fertilisation/intracytoplasmic sperm injection were found to have overall risk comparable with children conceived spontaneously.
authors.affiliation: School of Public Health, Section for Epidemiology, Aarhus University, Bartholins Allé 2, 8000 Aarhus C, Denmark. bjornbay@me.com
authors.forename: Bjørn
authors.initials: B
authors.lastname: Bay
authors.forename: Erik Lykke
authors.initials: EL
authors.lastname: Mortensen
authors.forename: Dorte
authors.initials: D
authors.lastname: Hvidtjørn
authors.forename: Ulrik Schiøler
authors.initials: US
authors.lastname: Kesmodel
mesh_terms: D000293:Adolescent; D002648:Child; D002659:Child Development Disorders, Pervasive / Q000453:epidemiology / Q000209:etiology; D003718:Denmark / Q000453:epidemiology; D005260:Female; D005307:Fertilization in Vitro / Q000009:adverse effects; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000453:epidemiology / Q000209:etiology*; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012042:Registries; D027724:Reproductive Techniques, Assisted / Q000009:adverse effects*; D012307:Risk Factors; D020554:Sperm Injections, Intracytoplasmic / Q000009:adverse effects; D013981:Tic Disorders / Q000453:epidemiology / Q000209:etiology