Chromosomal aberrations and month of birth.
D002869:Chromosome Aberrations; D002980:Climate; D004314:Down Syndrome / Q000453:epidemiology; D005060:Europe; D005260:Female; D005306:Fertilization; D006801:Humans; D007713:Klinefelter Syndrome / Q000453:epidemiology; D008297:Male; D012621:Seasons; D014314:Trisomy; D014424:Turner Syndrome / Q000453:epidemiology