The fourth session the Progress Educational
Trust's annual conference for 2012 'Fertility Treatment: A Life-Changing Event?' continued
the day's critical perspective on the evidential basis for the impact
of lifestyle factors on the outcome of fertility treatment and resulting children. This time it was the impact of alcohol and smoking that came under
scrutiny. Can the evidential link be made between these lifestyle choices and poorer
fertility outcomes or children's health?
Jean Golding, professor of paediatric and
perinatal epidemiology at the University of Bristol, said data collected from
its Avon Longitudinal Study of Parents and Children showed that the time taken
to conceive among those recruited increased if either the man or the woman
smokes, among other risks.
Interestingly, Professor Golding has also begun to
look at the effects of smoking on future generations. The researchers observed
how smoking may affect daughters' fertility by comparing grandmothers who
smoked and mothers who did not, with grandmothers and mothers who both did not
smoke. Initial results showed a difference in birth weight and length for boys, with no difference seen for girls.
These results identify smoking as a risk
factor — but what about alcohol? Guidance on lifestyle factors given to people undergoing
fertility treatment is not limited to smoking. The current NICE, National
Institute for Health and Clinical Excellence, guideline on
fertility, which is in the process of being updated, advises on the risks of
smoking, drinking alcohol, wearing tight underwear, body weight, recreational
drug use and even being involved in hazardous occupations.
Yet for all the concern, the evidential
basis remains unclear. Dr Allan Pacey, senior lecturer in andrology at the
University of Sheffield, said that his studies did not show smoking and alcohol
had an effect of the quality of sperm. Reviewing some of the studies on sperm
andrology — many of which were underpowered and poorly controlled, he said — the
evidence was not conclusive.
Part of the problem he explained was of a
lack of robust scientific evidence about the many known and unknown causes of
infertility and a poor understanding of sperm andrology. He explained that the
quality of sperm and infertility were not the same and although studies can be
cited to indicate that smokers demonstrate higher DNA damage in their sperm, or
that consuming alcohol makes a difference based on certain parameters measuring
semen quality. More research is needed.
Dr Pacey concluded there is very
little a man can do in terms of lifestyle about risks to fertility. Few
lifestyle factors, in fact, have a negative effect of motility or sperm
concentration. Testicles are 'robust', he said.
Professor Neil McClure of Queen's
University Belfast reflected on the inconclusiveness of current data. He
emphasised that a man's sperm count is extremely variable and can change all
the time, which is just one limitation to producing quality research.
Furthermore, as sperm is mostly taken from fertility patients attending
clinics, it has already been through a filtering process so may not be a
representative sample of the general male population.
Professor McClure also pointed out that
controlling for lifestyle factors is very difficult — what are the chances of
finding men who don't drink, don't smoke, don't wear tight underwear, don't use
laptops…and so on? His conclusion is that there is data that supports the view
that smoking is probably bad for fertility but on alcohol it is totally
Dr Ellie Lee, a reader in social policy and director of the Centre for Parenting Culture Studies at the University of Kent, argued that some Government guidance — for example, for pregnant women to avoid
drinking alcohol altogether — is not based on science. Instead, she identifies
a shift in political culture towards risk aversion, which has been promoted by
some sections of the media and the medical profession.
Dr Lee identifies examples of risk
reporting in the media (which has latterly moved from a sceptical to a more risk-averse position) but also places blame on some researchers who feel the
need to feed strong lines to the media. The words 'can' and 'effect' emphasises
risk, she says, giving the example of a quote from a recent study (coauthored by Jean Golding) that
linked moderate alcohol during pregnancy to a child's IQ. Even though an effect may be very small, on the basis of
a theoretical risk the message becomes take no risk.
For Dr Lee, it is unreasonable to prohibit
activities in people's private lives. She highlighted how every mother wants to
do the best for her children and will probably follow Government advice. Can
we blame them? But sending out strong public messages not supported by evidence
is not only risk averse, said Dr Lee, but is misleading and can promote fear. Fertility
patients already experience high levels of stress and emotional disturbance
(the topic of an earlier session, see BioNews 684).
There were a number of important messages
that emerged from this session, notably the need for well-designed studies to
provide robust evidence. Another
theme was that people should be educated at a young age about potentially
harmful lifestyle behaviour (advocated by Professor Golding and Dr Pacey) — this also remains true outside the fertility context.
The session also raised the prospect
that the connection between lifestyle and fertility is perhaps not one that
can be 'proved' to a satisfactory extent. Indeed, should we be even telling fertility patients what
to do? Either way the Government seems intent on introducing policy in this
Perhaps what is needed, rather than more studies producing even more
data, is a change in our attitudes towards risk. Dr Lee thinks the
Government should stay out of it; Professor McClure thinks the health agenda
has been hijacked by the press and the Government is being reactive, rather
than proactive. Such views serve to promote necessary debate on the merits and gaps in
current scientific understanding, which perhaps needs to be opened up to
greater public scrutiny.
PET is grateful to the conference's gold
sponsors, Merck Serono, silver sponsors London Women's Clinic and bronze
sponsors Ferring Pharmaceuticals.