Review throws doubt on evidence for National Chlamydia Screening Programme

By Lilian Anekwe

A new review has questioned the assumptions on which the National Chlamydia Screening Programme is based, after finding an ‘absence of evidence' for the assumption that the infection raises the risk of infertility.

Chlamydia screening is now on the fourth wave of its rollout in primary care, and was based on predictions that it would be cost-effective if 10% or more infected women subsequently went on to develop pelvic inflammatory disease – a recognised cause of infertility.

But a systematic review, conducted by a team of researchers at Health Protection Scotland, assessed 50 studies analysing the proportion of women of reproductive age who had one or more episodes of genital chlamydia infection who subsequently developed infertility.

The review found there were no robust clinical studies linking chlamydia with infertility, and

that: ‘There is a growing body of published data suggesting the reduction in reproductive morbidities resulting from chlamydia screening programmes may be overestimated'. The conclusions are published in the latest edition of the journal Sexually Transmitted Infections.

‘Because the absolute risk of infertility after chlamydial infection is unknown, policy makers find themselves ill-equipped to quantify the impact and therefore face uncertainty about the proportion of PID and infertility that is preventable by screening,' the researchers added.

Study leader Dr Lesley Wallace, an epidemiologist at Health Protection Scotland, said: ‘We may need to revise previous estimates regarding the level of tubal infertility attributable to genital chlamydia infection and this may have implications for future chlamydia testing policy.

‘However, we don't want to discourage the efforts being made to test and treat young people, as chlamydia can lead to a range of health problems. But we do need more research on the long term effects of chlamydia on infertility.'