Exogenous hormone use, reproductive history and risk of adult myeloid leukaemia.

BACKGROUND

A hormonal aetiology is one explanation for the lower incidence of myeloid leukaemia in women compared with men.

METHODS

In this population-based case-control study, we evaluated associations between exogenous hormone use and reproductive history and myeloid leukaemia, overall and by disease subtype.

RESULTS

We observed a suggestive association between oral contraceptive use and acute myeloid leukaemia (odds ratio=0.55, 95% confidence interval=0.32-0.96). Hormone replacement therapy and reproductive factors were not associated with risk.

CONCLUSION

Despite the biological plausibility for a role of oestrogen in leukaemogenesis, other aetiologic factors are likely to explain the differing incidence rates in males and females.