A principal investigator for the Human Reproductive Sciences Unit of the UK's Medical Research Council (MRC) has revealed that using certain cosmetics during the early stages of pregnancy could affect fertility in males in later life. Professor Richard Sharpe undertook research on rats, which showed that after exposure to certain chemicals commonly found in cosmetics such as perfume and household fabrics, the actions of male sex hormones were blocked and the animals suffered fertility problems.
Professor Sharpe and his Edinburgh-based team believe that there is a crucial window between eight and 12 weeks of pregnancy when the male reproductive system is established and male sex hormones are activated. It is at this time that if exposed to chemicals in cosmetics, the male fetus 'may not realise its full reproductive potential, including the size of the penis and testes, undescended testes or sperm count', he said. Professor Sharpe told the Scotland on Sunday newspaper that the 'male programming' window occurs far earlier in fetal development than previously thought, and it is at this time that male sex hormones such as testosterone are most active.
Speaking to BBC Scotland's news website, he said: 'If you are planning to become pregnant you should change your lifestyle... We would recommend you avoid exposure to chemicals that are present in cosmetics, anything that you put on your body that might then get through your body into your developing baby'. He added: 'It is not because we have evidence that these chemicals categorically cause harm to babies, it is only based on experimental studies on animals that suggest it is a possibility'.
Disorders of the male reproductive function can affect up to one in six young males with low sperm counts being the most common dysfunction. Professor Sharpe said that the chemicals he is concerned about may also increase the risk of suffering testicular cancer in later life.