Seasonal variations in the birth of the mentally deficient?
D001699:Biometry; D005260:Female; D006801:Humans; D008607:Intellectual Disability / Q000706:statistics & numerical data*; D036801:Parturition; D010507:Periodicity; D019989:Persons with Intellectual Disabilities; D012621:Seasons
MENTAL DEFICIENCY/statistics; PERIODICITY