Trends in sex-ratio, testicular cancer and male reproductive hazards: are they connected?

摘要: In the last few decades, male proportion of newborn babies has been decreasing in several populations. The changes are very small and without practical importance per se, but underlying biological mechanisms not known. same period, testicular cancer incidence increased, there indications sperm counts men available knowledge on factors that influence sex-ratio humans supports idea an excess girls offspring a man may be indicator reproductive hazards. Data from Danish case-control study show strong associations between cancer, low fertility M:F offspring. It is proposed as hypothesis exist common aetiological for sex-ratio, search causal involved focus agents can act prenatally to disrupt normal development differentiation organs.