Are sperm counts falling?

There have been many panicky reports over the last few years suggesting that sperm counts have dropped significantly over the past 50 years, probably due to environmental pollution damaging the reproductive systems of male foetuses. One study in the 1950s found that a normal sperm count was around 80–100 million sperm per ml of semen – today a count of 20–60 million sperm per ml is the norm.

However, the research is contradictory. One recent study reported that a group of men waiting for infertility treatment had similar sperm counts to men in the 1950s, although more sperm were found to be abnormal. Another study claimed that couples are actually becoming pregnant more quickly nowadays, meaning that either male fertility isn't in a state of decline, or couples are more clued up about how to maximise their chances of conception.