Type of delivery and reading, writing, and arithmetic learning in twin births.

This study analyses, in children born in twin births, the relationship between reading, writing and arithmetic learning, on the one hand, and type of delivery, on the other, controlling for the effect of interaction and/or confusion of third variables (maternal age at delivery, gestational age, fetal position, birthweight, 1-min Apgar score). In the planned retrospective cohort design, the exposed cohort consisted of children born by caesarean section, and the non-exposed cohort was comprised of children born vaginally. One hundred and twenty-four children born of twin births were evaluated during their first year of primary school: K-BIT tests were used to measure intelligence; the Evalúa-1 battery was used to assess reading, writing, and arithmetic ability; and the children's clinical histories were analysed for obstetric and neonatal variables. After applying binary logistic regressions for each dependent variable, it was found that caesarean delivery in twin births appeared as a possible independent risk factor for specific learning disabilities (LDs) in reading, writing, and arithmetic. Based on these results, further research using larger samples and at more advanced ages is required in order to analyse the influence of obstetric and neonatal variables on the processes underlying specific LDs.