The authors examined the association between month of birth & completed suicide among 76 major league baseball players. More than twice as many players born in August died by suicide than any other birth month. This association was statistically significant when birth month was corrected for differences in days of the month. The differences were even larger when expressed in times of birth month for those dying by suicide divided by the number of major league players born in each month. The association between birth month & suicide raises the possibility that prenatal factors may influence the inclination for suicide later in life. (13 refs.)