So much of the conversation around our fertility and reproductive health focuses on how our changes in lifestyle, such as deciding to start families later in life and stressful lifestyles, have negatively impacted our chances of conceiving. Yet a major factor that is impacting our reproductive health is mostly outside of our control: our environment. Chemical impact on fertility and overall health have to be brought to our attention as one could be exposed to these substances without knowing.
In the past few decades our exposure to environmental chemicals has continually increased while fertility rates and sperm counts have continually decreased, we are starting to understand that these two trends are closely related. Unfortunately the chemicals that are having this negative impact are not considered overtly ‘dangerous’ in fact they are the everyday chemicals that we surround ourselves with in our homes, store our food in and even put directly on our bodies in our cosmetics. These everyday chemicals including plastics (mainly BPA), parabens, phthalates and pesticides, are known as endocrine disruptors as they closely influence and disturb our natural hormone balance and hormone production. They have the potential to disrupt our hormonal health and fertility in a variety of ways.
We’re going to look at how these chemicals might be influencing both male and female reproductive health and what we can do about it, therefore increase your chances of conceiving and having a healthy pregnancy.
Which chemicals act as endocrine disruptors and where are they found?
The 2 chemicals that are known to be the most powerful disruptors of hormone production and reproductive health are phthalates and plastics. A plastic called bisphenol-A (BPA) is known to have a strong negative impact on female fertility by reducing egg quality and chances of conceiving. BPA can be found in plastic food containers and plastic bottles, receipts, canned foods and even, worryingly, in feminine hygiene products. The most significant source of exposure to BPA is in our diet as the majority of food and drink packaging contains BPA, a recent study found that BPA levels in urine decreased by 66% following three days during which participants avoided packaged foods
If you regularly treat yourself to a gel manicure and don’t leave the house without a spritz of perfume, there’s a good chance you’re exposing your body to phthalates. Phthalates are used to make plastics soft and pliable and are also used to produce vinyl and cleaning products. Phthalate exposure can also negatively impact sperm and egg quality and has been linked to increased risk of miscarriage.
How can environmental chemicals influence our fertility?
The problem with so many of the chemicals we are exposed to is that they are potent hormone mimickers, these chemicals are so similar to the hormones that our bodies produce that they can actually take their place and interfere with our body’s own production of hormones. Hormones are our body’s chemical messengers and these foreign chemicals can interfere with these messages and impact processes reliant on these hormones such as ovulation, sperm and egg production, conception and foetal development.
If you think about how the contraceptive pill works by providing synthetic hormones to interfere with and suppress ovulation you can start to understand how these hormone-mimicking chemicals can have a contraceptive-like impact on our fertility.
Influence on female fertility
A large body of research has proven the negative impact of these everyday chemicals on female reproductive health and chances of conceiving, the findings of this body of research are rather worrying. Women with higher levels of BPA circulating in their bloodstream were found to be 3 times more likely to miscarry and produce eggs that are of lower quality. Higher levels of BPA have been closely linked to reduced chances of conceiving through assisted conception – in fact, women with higher levels of BPA were two times less likely to become pregnant through fertility treatment.
Not only can BPA interfere with the activity of our reproductive hormones it can drive a perfect storm of hormonal imbalances in the female body: BPA can interfere with thyroid hormone activity, increase prolactin levels and drive insulin resistance. Imbalances in thyroid hormones and levels of prolactin can interfere with proper ovulation and chances of conceiving, while insulin resistance can drive PCOS. In fact women with PCOS were found to have levels of BPA up to 46% higher than women without PCOS.
The research on phthalates reports very similar findings: higher levels of phthalates were linked to increased chance of miscarriage. We know that phthalates inhibit production of oestrogen in a developing follicle and this interferes with both egg development and ability of an egg cell to fertilise.
Whereas BPA may promote PCOS, phthalates have been linked to the reproductive disorder endometriosis, in fact higher levels of phthalates were associated with double the likelihood of having endometriosis. Reducing exposure to both of these chemicals is an essential step in supporting reproductive health and boosting chances of conceiving.
Influence on male fertility
Male sperm counts have more than halved in the past 40 years and there is growing evidence that exposure to environmental chemicals has played a significant role in this downward trend. Male reproductive health is just as vulnerable as female reproductive health to the damaging impact of these chemicals.
Men who had higher levels of BPA in their bloodstream have been shown to be 30-46% more likely to produce lower-quality embryos and 3-4 times more likely to have a low sperm count. Phthlalates can directly interfere with male reproductive hormones by blocking the activity of androgens. Higher levels of phthlalate exposure was found to result in lower circulating testosterone and poorer quality semen. Men with higher phthlalate exposure were found to experience a longer time to achieve pregnancy with their partners compared to men with lower levels.
Impact during pregnancy
The impact of these chemicals can not only prevent us from achieving pregnancy but exposure can have a negative impact on pregnancy outcomes and the development of a growing baby. So by reducing our exposure we not only increase our chances of pregnancy but increase the chance of having a healthy pregnancy AND promote the health and development of our baby.
Babies born to mothers with higher levels of BPA were more likely to have a low birth weight or be born prematurely. Exposure to these chemicals during gestation may also have a negative impact on neuronal development: children born to mothers exposed to BPA were more likely to be anxious or hyperactive in childhood, while there is a link between a mother’s exposure to phthlalates and risk of developing autism in male offspring.
How to reduce exposure to these harmful chemicals
It might seem like an impossible task to avoid these harmful chemicals but a few straightforward steps can help you control your environmental exposure. The first step in reducing exposure is to walk through your home and get rid of as much plastic as you can. Aim to buy as much food as you possibly can without plastic packaging: cooking from scratch is a great way to instantly reduce your exposure to BPA. Reduce how often you wear perfume (do you need it every day?) and stop painting your nails. Even these simple steps can help you to significantly reduce your exposure to these everyday chemicals and promote good reproductive health. In the coming weeks we’re going to provide a comprehensive guide on how you can protect yourself and your reproductive health from the negative impact of these chemicals and optimise your reproductive health.
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