title: The effect of iodine supplementation in pregnancy on early childhood neurodevelopment and clinical outcomes: results of an aborted randomised placebo-controlled trial.
abstract: BACKGROUND
  Concern that mild iodine deficiency in pregnancy may adversely affect neurodevelopment of offspring has led to recommendations for iodine supplementation in the absence of evidence from randomised controlled trials. The primary objective of the study was to investigate the effect of iodine supplementation during pregnancy on childhood neurodevelopment. Secondary outcomes included pregnancy outcomes, maternal thyroid function and general health.
  
  
  METHODS
  Women with a singleton pregnancy of fewer than 20 weeks were randomly assigned to iodine (150 μg/d) or placebo from trial entry to birth. Childhood neurodevelopment was assessed at 18 months by using Bayley Scales of Infant and Toddler Development (Bayley-III). Iodine status and thyroid function were assessed at baseline and at 36 weeks' gestation. Pregnancy outcomes were collected from medical records.
  
  
  RESULTS
  The trial was stopped after 59 women were randomly assigned following withdrawal of support by the funding body. There were no differences in childhood neurodevelopmental scores between the iodine treated and placebo groups. The mean cognitive, language and motor scores on the Bayley-III (iodine versus placebo, respectively) were 99.4 ± 12.2 versus 101.7 ± 8.2 (mean difference (MD) -2.3, 95 % confidence interval (CI) -7.8, 3.2; P = 0.42), 97.2 ± 12.2 versus 97.9 ± 11.5 (MD -0.7, 95 % CI -7.0, 5.6; P = 0.83) and 93.9 ± 10.8 versus 92.4 ± 9.7 (MD 1.4, 95 % CI -4.0, 6.9; P = 0.61), respectively. No differences were identified between groups in any secondary outcomes.
  
  
  CONCLUSIONS
  Iodine supplementation in pregnancy did not result in better childhood neurodevelopment in this small trial. Adequately powered randomised controlled trials are needed to provide conclusive evidence regarding the effect of iodine supplementation in pregnancy.
  
  
  BACKGROUND
  The trial was registered with the Australian New Zealand Clinical Trials Registry at http://www.anzctr.org.au . The registration number of this trial is ACTRN12610000411044 . The trial was registered on 21 May 2010.
authors.affiliation: Women's & Children's Health Research Institute, 72 King William Road, North Adelaide, SA, 5006, Australia. jo.zhou@adelaide.edu.au.|School of Agriculture, Food & Wine, University of Adelaide, Waite Campus, Waite Road, Urrbrae, SA, 5064, Australia. jo.zhou@adelaide.edu.au.
authors.forename: Shao J
authors.initials: SJ
authors.lastname: Zhou
authors.affiliation: Department of Human Nutrition, University of Otago, PO Box 56, Dunedin, 9054, New Zealand. sheila.skeaff@otago.ac.nz.
authors.forename: Sheila A
authors.initials: SA
authors.lastname: Skeaff
authors.affiliation: School of Population Health, University of Adelaide, 178 North Terrace, Adelaide, SA, 5005, Australia. philip.ryan@adelaide.edu.au.
authors.forename: Philip
authors.initials: P
authors.lastname: Ryan
authors.affiliation: Department of Obstetrics and Gynaecology, Royal Women's Hospital, Cnr of Flemington Road and Grattan Street, University of Melbourne, Melbourne, VIC, 3052, Australia. lwd@unimelb.edu.au.|Clinical Sciences, Murdoch Childrens Research Institute, Flemington Road, Melbourne, VIC, 3052, Australia. lwd@unimelb.edu.au.|Department of Paediatrics, University of Melbourne, 50 Flemington Road, Melbourne, VIC, 3052, Australia. lwd@unimelb.edu.au.
authors.forename: Lex W
authors.initials: LW
authors.lastname: Doyle
authors.affiliation: Clinical Sciences, Murdoch Childrens Research Institute, Flemington Road, Melbourne, VIC, 3052, Australia. peter.anderson@mcri.edu.au.|Department of Paediatrics, University of Melbourne, 50 Flemington Road, Melbourne, VIC, 3052, Australia. peter.anderson@mcri.edu.au.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Anderson
authors.affiliation: Department of Obstetrics and Gynaecology, Royal Women's Hospital, Cnr of Flemington Road and Grattan Street, University of Melbourne, Melbourne, VIC, 3052, Australia. louise.kornman@thewomens.org.au.
authors.forename: Louise
authors.initials: L
authors.lastname: Kornman
authors.affiliation: Women's and Children's Health Network, 72 King William Road, North, Adelaide, SA, 5006, Australia. andrew.mcphee@sa.gov.au.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Mcphee
authors.affiliation: Women's & Children's Health Research Institute, 72 King William Road, North Adelaide, SA, 5006, Australia. lisa.yelland@adelaide.edu.au.|School of Population Health, University of Adelaide, 178 North Terrace, Adelaide, SA, 5005, Australia. lisa.yelland@adelaide.edu.au.
authors.forename: Lisa N
authors.initials: LN
authors.lastname: Yelland
authors.affiliation: Women's & Children's Health Research Institute, 72 King William Road, North Adelaide, SA, 5006, Australia. maria.makrides@sa.gov.au.|School of Paediatrics & Reproductive Health, University of Adelaide, Frome Road, Adelaide, SA, 5005, Australia. maria.makrides@sa.gov.au.|South Australian Health and Medical Research Institute, North Terrace, Adelaide, SA, 5000, Australia. maria.makrides@sa.gov.au.
authors.forename: Maria
authors.initials: M
authors.lastname: Makrides
mesh_terms: D000328:Adult; D000367:Age Factors; D001315:Australia; D002657:Child Development / Q000187:drug effects*; D002663:Child Language; D003071:Cognition / Q000187:drug effects; D019587:Dietary Supplements / Q000009:adverse effects; D004311:Double-Blind Method; D057239:Early Termination of Clinical Trials; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D000068097:Maternal Health; D009043:Motor Activity / Q000187:drug effects; D009420:Nervous System / Q000187:drug effects* / Q000254:growth & development; D009483:Neuropsychological Tests; D009520:New Zealand; D011193:Potassium Iodide / Q000008:administration & dosage* / Q000009:adverse effects; D011247:Pregnancy; D011248:Pregnancy Complications / Q000175:diagnosis / Q000503:physiopathology / Q000517:prevention & control*; D011295:Prenatal Care / Q000379:methods*; D012107:Research Design; D013960:Thyroid Function Tests; D013961:Thyroid Gland / Q000187:drug effects* / Q000503:physiopathology; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D011193:Potassium Iodide