CDC Kerala 13: Antenatal, Natal and Postnatal Factors Among Children (2-6 y) with Autism - A Case Control Study

Objectives To compare antenatal, natal and postnatal factors among children between 2-6 y of age with autism and a control group of normal children. Methods One hundred and forty three confirmed cases of 2-6 y-old children with autism, attending autism clinic of Child Development Centre, who had a CARS score of >= 30 were included in the study. Two hundred normal children in the same age group were recruited from the well-baby/immunization clinic of SAT Hospital, Thiruvananthapuram. Data was collected using a structured pre-piloted questionnaire consisting of 21 antenatal, 8 natal and 6 postnatal risk factors. Results The multivariate analysis on antenatal, natal and postnatal possible risk factors for autism showed statistically significant high odds ratios for (i) excess fetal movement (OR=11.44; 95 % CI: 2.85 - 45.98); (ii) maternal respiratory infection/asthma (OR=6.11; 95 % CI: 1.56-24.02; (iii) maternal vaginal infection (OR=5.20; 95 % CI: 1.72 - 15.73); (iv) maternal hypothyroidism (OR=4.25; 95 % CI: 1.38-13.07) and (v) family history of neuro-developmental disorders (OR=2.90; 95 % CI: 1.72 - 4.88). Conclusions This case control study involving 143 children between 2 and 6 y with autism as per CARS criteria and a control group of 200 normal children has shown that excess fetal movement, maternal respiratory infection/asthma, maternal vaginal infection, maternal hypothyroidism and family history of neuro-developmental disorders are possible risk factors for autism.