PARENTAL AGE IN RELATION TO RISK OF BREAST-CANCER

Data from a population-based case-control study were analyzed to evalu ate risk of breast cancer among women according to parental age at the time of subject birth. Between 1988-91, breast cancer cases (n = 1, 2 53) were obtained from the statewide tumor registry in Wisconsin. Conc urrently, population controls (n = 1, 121) were randomly selected from driver's license lists (if under age 65) and Medicare beneficiary fil es (if 65-74 years), Information regarding parents' ages and breast ca ncer risk factors was obtained by telephone interview. Relative risk e stimates were very slightly elevated with increasing maternal age, alt hough no consistent trend of increasing risk was observed (P for trend = 0.38). No association between paternal age and breast cancer risk w as observed (P for trend = 0.98). Older maternal or paternal age was n ot associated with risk among any of the subgroups examined, except fo r daughters who had late age at first birth. These findings are consis tent with the majority of studies that have found little or no associa tion between parental age and breast cancer risk.