Associate Professor Tim Moss, a biomedical researcher and expert at men’s health organisation Healthy Male, is unmoved by claims of an impending Spermageddon. According to him, studies reporting an almighty sperm crash since the 1970s are a case of “shit in, shit out”.
“We know that if you take a semen sample and send it to two laboratories, we get different answers,” Moss says. “It’s really imprecise. That’s the shit going in that produces unreliable results.”
Other fertility experts have branded the data from the 70s as being of bad quality because less sophisticated semen analysis in past decades may have overestimated sperm counts, and much of that past data is missing key information including the donors’ age. Sperm counts themselves fluctuate on short timescales depending on factors such as arousal; a 2015 study showed men ejaculate higher volumes of more spritely sperm when shown new porn videos compared with those they have already watched.
But there is one thing experts on both sides of the Great Sperm Debate agree on: for a cell so crucial to human existence, we know precious little about it. Scientists have galvanised around the rather extraordinary statistic that, in couples undergoing IVF at least partly due to male fertility problems, 77 per cent of those male infertility cases cannot be explained.
The state of data is so bad that even the male fertility rate is something experts guess at, Moss says: “Everybody seems to say that in up to 50 per cent of infertile couples, there is a male factor that contributes to it. But those data are based on a study of three regions in France conducted in the early 80s. We just don’t have good quality data about the prevalence of infertility in males.
“The infertility data that we use in Australia comes from the Women’s Health Survey, where they ask women about their experiences trying to get pregnant. We haven’t asked the men.”
US professor Dr Shanna Swan
declared humanity was facing a
“global existential crisis” following
her research into sperm counts.
New male fertility guidelines, launched this month, urge doctors to assess both men and women from the get-go when couples seek fertility treatment. The guidelines aim to shift the onus of fertility treatment from women and to improve outcomes for men; it’s mandatory under the guidelines that men drop their dacks for physical examinations, which can lead to the quick diagnosis of easily fixed problems such as varicocele (varicose veins in the testicle, which reduce sperm production). But experts also hope greater emphasis on men’s reproductive health will help shed light on what’s behind unexplained male infertility and chip away at the paucity of data.
What the new guidelines tell GPs
Offer an initial evaluation of male fertility to the concerned man and/or couple experiencing infertility. The evaluation should include a reproductive history, physical (including scrotal) examination and semen analysis. Mandatory.For initial infertility evaluation, both male and female partners should undergo concurrent assessment. Mandatory.Offer semen analysis according to current WHO Laboratory Manual for the Examination and Processing of Human Semen. If the first semen analysis is abnormal, perform a second semen analysis approximately six weeks afterwards, or longer if clinically indicated. Mandatory.Do not perform antisperm antibody testing in the initial evaluation of male infertility. Recommended. Do not routinely perform scrotal ultrasound in the initial evaluation of male infertility. Recommended.Advise all men to undertake monthly testicular self-examination until the age of 55. Recommended.
Source: Healthy Male
Professor Rob McLachlan, medical director at Healthy Male and co-creator of the guidelines, takes a “guilty until proven innocent” approach to the role of PFAS and plastic chemicals, but believes most severe cases of male infertility are probably down to genetics. Even if average sperm rates are suffering, on the whole they remain well above levels needed to conceive, and plunging birth rates are down to societal pressures rather than sperm counts, he says.
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But the question of sperm health remains vital from a public health perspective; men with greater sperm counts and faster swimmers tend to live longer. McLachlan emphasises factors men can control to boost sperm health.
“You shouldn’t be obese,” he says. “You should be exercising. You should not be smoking – that’s very bad for sperm. I’m very worried about this anti-vaccination madness. Your son must be immunised against mumps – if you get it after puberty that can lead to complete sterility.
“Women are told to not smoke and not drink and lose weight before they have a baby. We now know that being a healthy father at the time of conception – which means getting your act together well before you make the baby – is just as important.”
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