Learning Disabilities in Reading and Writing and Type of Delivery in Twin Births.

The aim of this study was to analyse the relationship between the type of delivery (vaginal or caesarean), as a risk factor, and the likelihood of having learning disabilities in reading (reading accuracy) and writing (phonetic and visual orthography), controlling for the interaction and/or confounding effect of gestational, obstetric, and neonatal variables (maternal age at delivery, gestational age, foetal presentation, Apgar 1, and newborn weight) among six-year-old children born in twin births. In this retrospective cohort study, the exposed and non-exposed cohorts consisted of children born by caesarean section and vaginal delivery, respectively. A total of 124 children born in twin births were evaluated in year one of primary education. Intelligence was measured using the K-BIT test; reading and writing variables were evaluated using the Evalúa-1 battery of tests, and clinical records were used to measure gestational, obstetric, and neonatal variables. Binary logistic regressions applied to each dependent variable indicated that caesarean delivery is a possible independent risk factor for difficulties in reading accuracy and phonetic and visual orthography. Future research using larger samples of younger children is required to analyse the relationship between obstetric and neonatal variables and the different basic indicators of reading and writing.

Exposure to synthetic oxytocin during delivery and its effect on psychomotor development.

The main objective is to examine the influence of oxytocin administration during delivery on psychomotor development at age five years. This was a retrospective cohort study involving two groups: children of mothers exposed vs. not exposed to oxytocin during labor. Of the 7,465 newborns registered in our maternity service during 2006 we randomly selected an initial sample of 400 children. Of these, 146 children were assessed using the motor scale of the Battelle Developmental Inventory. Other predictor variables that could potentially act as confounders and/or interact with the main relationship were also examined. The data were subjected to bivariate analysis, estimates of measures of strength of association, stratified analysis and multivariate binary logistic regression. The results indicate that exposure to synthetic oxytocin during delivery is an independent risk factor for a delay in gross and fine motor development. This was the case after controlling for the variables duration of labor and sex of the newborn, none of which modified the effect of oxytocin on gross and fine motor development. However, sex of the newborn were shown to be confounding gross motor development. In light of these results, and with the aim of preventing possible psychomotor alterations, further studies are now needed to analyze the effect that the oxytocin dose and the duration of perfusion may have on children's subsequent development.