In-Utero p,pʼ-DDE Exposure and Child Neurodevelopment at 48 Months of Age: A Mexican Cohort

Abstract

ISEE-0168 Background and Objectives: Prenatal p,p'-DDE (DDE) exposure during the first trimester of pregnancy is associated with a significant reduction in child motor neurodevelopment during the first year of life. The persistence of this effect beyond twelve months of age is not sufficiently documented. In this report, we assessed prenatal DDE levels and infant neurodevelopment (IND) at 48 months, in relation to previous tests performed in this child cohort. Methods: The cohort was assembled in January 2001, in an endemic malaria zone in Morelos, Mexico, where DDT was used until 1998. Women of reproductive age were interviewed before, during, and after pregnancy. IND was evaluated through the first 30 months of age using the Bayley Assessment Scale. At 48 months of age, the McCarthy Scale of Children's Abilities (MSCA), including six subscales (general cognitive, verbal, perceptual-performance, quantitative, memory, and motor) was applied (119 children). Home stimulation was determined using the HOME Scale. DDE maternal levels during pregnancy were also available for this report. Results: No significant associations between prenatal DDE exposure and the MSCA were detected. Breastfeeding (≥12 weeks) had no significant positive effect on any subscale of the MSCA, except for motor. Children who received more home stimulation showed a significant performance in perceptual and motor subscale scores. Conclusions: Our results suggest that prenatal DDE exposure, primarily during the first trimester of pregnancy, is not permanently associated to IND impairment. Breastfeeding and home stimulation may be key factors in preventing IND deficiencies.