The authors analysed all suicides & deaths from undetermined injury reported between 1979-2001 in England & Wales for persons born between 1955 & 1966, using Poisson & negative binomial generalised linear models with seasonal components. A sample size of 26,915 subjects was generated. Birth rates of people who later kill themselves show disproportionate excess for April, May, & June compared with the other months. Overall, an increase of 17% in the risk of suicide was found for people born in the peak month (spring-early summer) compared with those born in the trough month (autumn-early winter). This risk increase was larger for women than for men. (35 refs.)