MATERNAL THYROID PEROXIDASE ANTIBODIES DURING PREGNANCY - A MARKER OFIMPAIRED CHILD-DEVELOPMENT

Women with antibodies against the enzyme thyroid peroxidase [TPO-Ab; f ormerly microsomal antibodies (MsAb)] are at particular risk for devel oping postpartum thyroid dysfunction; the latter is significantly asso ciated with postpartum depression. Although the negative effect of pos tpartum maternal depression on child development is well documented, t he consequences of elevated titers of TPO-Ab during pregnancy and subs equent postpartum thyroid dysfunction on child development are not kno wn. In a prospective study of a cohort of 293 pregnant women, the occu rrence of TPO-Ab during gestation, thyroid dysfunction, and depression was investigated. Five years ae ter delivery, child development was a ssessed in 230 children of the original cohort using the Dutch transla tion of the McCarthy Scales of Children's Abilities. Children of women with TPO-Ab during late gestation (n = 19, with normal thyroid functi on) had significantly lower scores (by t test) on the McCarthy Scales of Children's Abilities than antibody-negative women. The difference o n the General Cognitive Scale, which reflects IQ scores, was substanti al (10.5 points; t = 2.8; P = 0.005). After correction for possibly co nfounding variables, maternal TPO-Ab during gestation was found to be the most important factor related to the scores on the General Cogniti ve Scale (odds ratio = 10.5; 95% confidence interval = 3-34; P = 0.003 ). We conclude that children of pregnant women who had elevated titers of TPO-Ab but normal thyroid function are at risk for impaired develo pment.