Acta Obstetricia et Gynecologica. 2010; Early Online, 1396–1402 RANDOMIZED CONTROLLED TRIAL Maternal calcium supplementation during pregnancy and dental caries of children at 12 years of age: follow-up of a randomized controlled trial EDUARDO BERGEL 1 , LUZ GIBBONS 2 , MARÍA G. RASINES 3 , ALEJANDRA LUETICH *4 & JOSÉ M. BELIZÁN 2 1 Department of Reproductive Health and Research, World Health Organization, Geneva, Switzerland, 2 Institute for Clinical Effectiveness and Health Policy, Buenos Aires, Argentina, 3 Argentine Odontological Association, Evidence Based Dentistry Commission, Buenos Aires, Argentina, and 4 Rosario Odontological Association, Rosario, Argentina Abstract Objectives. To evaluate if calcium supplementation during pregnancy could have any influence on primary dentition measured as the reduction of dental caries of the child. Design. Individual randomized controlled trial. Setting. One hospital in Rosario, Argentina. Population. Random sample of 195 12-year-old children from a follow-up study of 614 women who were randomized during pregnancy to calcium supplementation or placebo. Methods. An independent researcher blinded to the group where the mothers were assigned performed a dental examination of the children. Main outcome measures. Proportion of children with at least one decayed, missing or filled teeth (DMFT/dmft) and mean number of decayed, missing or filled surfaces (DMFS/dmfs) per children. Results. Ninety-eight children were assessed in the calcium supplementation group and 97 in the placebo group. 63.3% of the children whose mother took calcium supplementation had at least one DMFT/dmft compared to 86.6% in the placebo group (<0.001). The children whose mother received the intervention had a 27% reduction in the risk of developing at least one DMFT/dmft (RR: 0.73, CI 95%: [0.62; 0.87]). Conclusions. This study shows a modeling effect of calcium intake during pregnancy on dental caries of the offspring. At around 12 years of age children whose mothers received calcium supplementation when pregnant showed a significant reduction in dental caries. Key words: Fetal modeling, dental caries, calcium intake, pregnancy Introduction Many studies are supporting the hypothesis that adult life can be ‘modeled’ during intrauterine life implying that nutritional intrauterine deficiencies could be associated with adult diseases such as hypertension, diabetes and obesity (1). Our group have shown that maternal calcium supplementation during pregnancy involves lower rates of hypertension in the progeny in humans and animals (2–3). In year 1995–1996, we conducted a follow-up of children of around 7 years of age whose mothers participated in a randomized controlled trial during their pregnancy that compared calcium supplemen- tation to placebo for preventing pre-eclampsia (2). Women where blinded to the allocated intervention and still remain blinded at the time of the follow-up. During our interview some mothers mentioned that they had observed that their children had a better dentition and less dental complications compared with other children including their own siblings. Our first reaction was to consider that they could have been influenced by believing they had received calcium supplementation during pregnancy and Correspondence: Luz Gibbons, Institute for Clinical Effectiveness and Health Policy, Viamonte 2146 (3er Piso), Buenos Aires C1056ABH, Argentina. E-mail: lgibbons@iecs.org.ar *We deeply regret that Dr Alejandra Luetich, one of the authors of this paper and a prominent and enthusiastic scientist, has deceased after the completion of this study. (Received 27 May 2010; accepted 19 August 2010) ISSN 0001-6349 print/ISSN 1600-0412 online Ó 2010 Informa Healthcare DOI: 10.3109/00016349.2010.518228