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Environment, lifestyle and fertility

About one couple in six has difficulty conceiving, and this number is steadily increasing. One hypothesis that has been suggested to explain this trend is the influence of behavioural and environmental factors, Indeed, there seems to be a correlation between the increased incidence of infertility and non-optimal lifestyles and the use of certain chemical products.
Several of these factors (those involving diet, sports, smoking, alcohol, etc.) can be positively altered, so to improve the chances of achieving pregnancy, either naturally or with Assisted Reproductive Technology (ART) treatments, although they alone cannot fully account for infertility in the couple.
Environment and fertility


Exposure to certain environmental contaminants, such as heavy metals (arsenic, mercury, lead, aluminium, etc.), organochlorine pesticides, solvents or phthalates, has a harmful effect on the regularity of menstrual cycles, the possibility of miscarriage and semen parameters. One of the possible biological mechanisms is that of endocrine disruption. Endocrine disruptors are molecules that mimic, alter or block the action of hormones. At present it is not known what percentage of infertility disorders can be explained by exposure to these kinds of environmental contaminants. Moreover, there are hundreds of different contaminants that can act simultaneously, making it impossible to determine how important a role each one plays. In addition they sometimes have synergistic interactions, so that it is very difficult to assess the overall effect of the cocktail of contaminants to which people are exposed.


Practical measures:

– Consume more organic food in order to avoid exposure to pesticides. Otherwise peel fruits, vegetables and edible plants (since pesticides are usually concentrated in their skins).

– Favour bio household products and cosmetics bought from organic stores, that are as simple as possible.

– Avoid heating food in plastic food packaging in microwave ovens (use glass containers instead).


Diet and fertility

More and more studies are focussing on the connection between diet and fertility. On the whole, the concrete evidence deriving from these studies is relatively limited, mainly because they either tend to be based on dietary questionnaires with self-declarations, or they examine quite specific foodstuffs and categories of food, they provide varying definitions of what constitutes a healthy diet and they contain many biases and confounding factors.
However, most of these studies reach similar conclusions, i.e. that a varied, healthy and balanced diet favours fertility, both female (natural or following in vitro fertilisation) and male (assessed by means of semen parameters), and they tend to put special emphasis on the so-called “Mediterranean diet”, which is high in unsaturated fatty acids (especially Omega 3), and low in saturated fats. They also stress the need to limit the intake of sugars, artificial sweeteners, and red and processed meat.
As regards dietary supplements, an excessive as well as an insufficient intake may be detrimental to fertility. Folic acid supplements are recommended for women who wish to become pregnant, but apart from this vitamin, no scientific evidence is currently available regarding the value of multi-vitamin supplements. For men, no scientific test is currently available regarding the possible benefits of vitamin supplements, although certain antioxidants may prove useful, but they are indicated only in specific situations.


Practical measures:

  • At present, no particular diet, foodstuffs or categories of foods has been officially recognized to have any beneficial effects on fertility.
  • Nevertheless, it seems that a varied, balanced and healthy diet encourages pregnancy for both men and women.
  • A diet should be favoured that is rich in fruit and vegetables, fish, cereals and natural antioxidants.
  • The consumption of red meat, fats, sugars and artificial sweeteners should be limited.





Smoking and fertility

Giving up the smoking of tobacco is necessary in order to protect the health of the fotus, but it is also a key factor in achieving pregnancy. In fact, smoking affects both male and female fertility, increases the time necessary for conceiving and reduces the chances of successful ART treatment.
In women, one result of smoking is that it takes longer to conceive a child, and its harmful effects on the number and quality of the oocytes (egg cells), as well as the chances of successful embryo implantation, have been clearly demonstrated. Furthermore, women who smoke tend to reach the menopause several months earlier (from 9 to 24 months according to studies) than women who do not!
In men, it is widely recognized that smoking adversely affects most sperm parameters. There is a decrease in the number and mobility of spermatozoa, as well as a reduction in their quality, with the presence of morphological abnormalities and the fragmentation of their DNA. These alterations are however reversible and giving up smoking has beneficial effects (within a period of 3 to 6 months).
The deleterious effects of smoking on the results of in vitro fertilization (IVF) techniques are also well known. Overall, there are fewer embryos in women who smoke and poorer implantation rates. Most ART centres therefore ask their patients to give up smoking before any treatment is administered, in order to improve the chances of success.


Practical measures:

  • Although smoking tobacco does not direct necessarily lead to infertility, it is particularly harmful to a couple’s fertility.
  • The effects of giving up smoking on the improvement of sperm parameters are quickly obtaine
  • The results of IVF are not as good for women who smoke as for those who do not.
  • Giving up smoking should therefore be obligatory for any couple who want to conceive a child




Alcohol and fertility

Drinking alcohol is another factor which affects both male and female fertility. In women, there is a link between excessive alcohol consumption and infertility, while in men chronic excessive drinking leads to alterations to sperm, and can sometimes lead to azoospermia, although these changes appear to be reversible after giving up. Similarly, a decrease in the quality and quantity of sperm has been observed in the days following excessive alcohol consumption.
In addition, solid data is available on the harmful effects of drinking in the month prior to IVF, even for relatively low levels of consumption (1 glass of wine per day for 4 days a week).

Practical measures:

  • Although there is no clear consumption threshold that should not be exceeded, an expert report by Santé publique France (the French governmental public health agency) and The French National Cancer Institute (INCa) has proposed a limit or threshold of 10 standard measures or units per week and no more than 2 standard units per day. 1 standard unit = 10 g of pure alcohol (or 25 cl of beer, 10 cl of wine or champagne, 2.5 cl of whisky).
  • During pregnancy it is strongly recommended not to consume any alcohol, since even occasional consumption is known to have possible effects on the baby. Thus, in cases of IVF, it is advisable to abstain from alcohol as soon as the embryo transfer has been carried out.




Exposure to heat and male fertility

It has been well known for many years that chronic exposure to sources of heat affects the production of sperm and can therefore be a factor affecting male infertility. The alterations to sperm that have been observed are reversible if the exposure to heat ceases

Practical measures for men:

  • Avoid staying in a sitting position for long periods of time
  • Avoid taking hot baths, saunas and hammams.
  • Avoid putting your laptop computer on your lap.
  • Wear loose-fitting underwear and clothing that is not too tight.


Public consultations (sector 1, without exceeding fees): contact the appointment office of Antoine Béclère Hospital: 01 41 07 95 95


Private consultations (sector 2, with overruns): contact Ms. Céline Delattre at or celine.delattre@aphp.fr