Prenatal and Perinatal Factors and Risk of Cancer in Middle and Older Adulthood among Men

Background: Prenatal factors have been associated with risk of cancers later in life, although studies in men have largely been case-control and focused on birth size only. Methods: We used data from 5,845 men in the Health Professionals Follow-up Study (HPFS) to prospectively examine associations between several prenatal and perinatal factors and incident adult cancer risk. In 1994, mothers of participants reported information on characteristics and behaviors related to their pregnancy with their sons. We used multivariable Cox proportional hazards models to calculate HRs and 95% confidence intervals (CI) of associations between prenatal and perinatal risk factors and cancer risk. Results: During 20 years of follow-up, 1,228 incident cases of overall cancer were documented. Men with a birth weight of >= 4 kg had a 21% increased risk of overall cancer (HR, 1.21; 95% CI, 1.021.43) compared with those with a birth weight of 2.5 to 3.9 kg. Greater weight gain during pregnancy (>13.6 kg vs. 6.8-8.6 kg) was also associated with a higher risk of overall cancer (HR, 1.22; 95% CI, 1.02-1.46), and was stronger for men whose mothers had a prepregnancy BMI< 21 kg/m(2) (HR, 1.30; 95% CI, 1.00-1.67) compared with body mass index (BMI) >= 21 kg/m(2) (HR, 1.14; 95% CI, 0.85-1.51). There was no association between maternal age and overall cancer risk. Conclusions: Higher birth weight and maternal weight gain are associated with increased cancer risk in adult men. Impact: Our findings support the hypothesis that the in utero environment plays a role in the etiology of cancer in middle and older adulthood.