Endocrine disruptors and their effects on fertility

What are EDCs?

EDCs are pervasive chemicals which can interfere with the natural function of your endocrine system by either mimicking or blocking its normal processes. The endocrine system is responsible for regulating hormone production and secretion and plays a critical role in reproductive health and function, so any interruptions to this system can result in abnormal hormone production, menstrual cycle irregularities, impaired ovulation, early menopause and even sub- or infertility. Examples of EDCs include pesticides, heavy metals, bisphenol A (BPA), parabens and diethylstilbestrol (DES).

Interestingly, the increasing prevalence of reproductive diseases and associated decline in reproductive health and function worldwide over the last century have been attributed to the rising presence of these environmental substances and chemicals we’re being exposed to. We now know that some of these EDCs can interrupt the feedback loops of our hormone production and homeostatic system, meaning we’re over- or underproducing key reproductive hormones.

We’re exposed to EDCs in our air, water, personal care products, plastic containers, and soil, with the major method of human ingestion being through the food we eat. Meat, fish, dairy and vegetables are exposed to heavy metals, pesticides and other pollutants, as well as processing aids and steroids used in food production – all of which enter our bodies when we consume contaminated foods. Ultimately, almost all food and drink we consume contain some residue of EDCs, however, there is plenty we can do to limit our exposure and mitigate any harm and damage to our health and fertility it may be causing.

Before we get into how to avoid these EDCs in your daily life, let’s touch on a few key EDCs which may potentially be posing a threat to your health and fertility.

Pesticides

Pesticides are primarily used in agriculture and farming to prevent, destroy or reduce the spread of weeds, bacteria, fungi and other organisms considered to be pests. There are strict regulations and limits in place to control the use of pesticides and avoid harm to human health, as excessive consumption of these chemicals can be harmful or poisonous. 

Pesticides have been found to compromise female reproductive health by impairing the ovary’s ability to produce sex steroid hormones, disrupting uterine structure and function, and reducing fertility by increasing the time it takes to fall pregnant and increasing the risk of foetal complications or loss. Exposure to pesticides during adulthood has also been shown to lower the average age women enter menopause, meaning their fertile window shortens substantially.

Heavy Metals

Heavy metals can be found in cigarettes, alcohol, supplements, and some contaminated food and water and even air. Some, including arsenic, are naturally occurring in the environment, with some geographical areas containing more arsenic in the soil and water than others, increasing the risk of exposure for people living in these areas.

Lead and mercury exposure can also cause harm to your health, and can occur via inhalation or ingestion of contaminated water or air. Mercury, in particular, is more common given the most common method of exposure is by eating contaminated fish, with some species such as tuna being renowned for possessing higher quantities of mercury. This is a key reason for dietary guidelines recommending limited consumption of mercury-rich fish as part of a healthy diet.

Heavy metal exposure has been linked to reduced ovarian follicular health, fertility and pregnancy outcomes in women, and strongly interferes with female reproductive health.

Bisphenol A (BPA) and Di-Ethylhexyl Phthalate (DEHP)

BPA and DEHP are chemicals used to make plastics more flexible. However, over time we’ve come to realise these chemicals can leach out of plastics and into our foods, personal care products, receipts etc, only to be later consumed unknowingly by humans. This discovery has let to the introduction of some restrictions around the use of BPAs in children’s products, receipt paper and some other products, however the resulting development of alternative bisphenols are thought to have very similar, if not equivalent, toxic effects on humans, meaning much more needs to be done to reduce our consumption and exposure.

Several studies have found these chemicals negatively impact female fertility, impairing reproductive health and chances of conceiving in women.

Parabens

Parabens are a group of chemicals commonly used for their preservative properties in cosmetic and beauty products, which mimic the actions of the hormone oestrogen in your body. As a result, parabens can interfere with your normal hormone production and function, affecting both female and male fertility, reproductive health and birth outcomes.

Research has linked paraben exposure to reduced reproductive hormone levels and increased time taken to fall pregnant in women.

There are various other types of EDCs, however as you can see excessive consumption or exposure to these chemicals has negative impacts on various aspects of reproductive health, and can have terrible consequences for your fertility if left unmanaged.

How do EDCs affect fertility?

The endocrine system is complex, so the ways in which EDCs act on it to disrupt fertility can be various and difficult to determine. 

In basic terms, EDCs can either block or mimic the effects of sex hormones in your body including oestrogen and testosterone, thereby “tricking” your body into thinking it’s producing more or less of these hormones than it actually is. As a result, this impacts your reproductive system function and hormone secretion.

They also have negative impacts on both egg and sperm health and quantity, which further impairs healthy fertility. For example, BPAs can interrupt the neuroendocrine pathways involved in reproductive health, and can also impair embryo implantation in women. Early exposure to EDCs in females can also shorten their reproductive lifespan, leading to an earlier onset of puberty, longer menstrual cycles, and early menopause in some women. Heavy metals can also shorten a woman’s fertile window even at low levels of exposure.

We know fertility relies on a delicate balance between androgens (including testosterone) and oestrogen, so any substance which interferes with this balance naturally has a negative effect on your fertility and chances of conceiving.

EDCs can have different effects on male and female fertility, so let’s look a little closer.

Female fertility

Women with high exposure to BPA, pesticides and plastics are at much higher risk of infertility, as well as reproductive disorders including endometriosis, polycystic ovarian syndrome (PCOS) and premature ovarian failure (POF), all of which may affect a woman’s chances of conceiving. The prevalence of each of these conditions continues to increase, posing a threat to ovarian development and function in females. 

And as we’ve already discussed, various EDCs interfere with normal production of oestrogen in women, affecting ovarian function, menstrual cycle regularity, ovulation and reproductive function in women.

Male fertility

Over the past half-century, sperm counts and quality have declined dramatically. Now, male infertility is predicted to account for 40-50% of infertility complications, with sperm morphology and motility abnormalities increasing substantially at the same time as sperm concentration fell from 1.5-3% annually. These statistics have been more dramatic in regions associated with greater EDC exposure, suggesting endocrine-disrupting chemicals are a large contributing factor to declining male fertility.

EDCs can lead to poor semen quality and disrupted spermatogenesis. In fact, excessive exposure to BPAs during pregnancy can disrupt the blood-testis barrier of the foetus, potentially leading to male infertility in adulthood.

How can you reduce your exposure?

Evidently, if you’re looking to support your fertility and enhance your chances of conceiving a healthy baby, both parents should look to reduce their exposure to EDCs as much as possible.

Some of the ways in which you can reduce your consumption and intake of EDCs include:

• Avoid plastic containers. Never reheat food in plastic, as the BPAs will leach into your food, and you’ll end up eating them. Instead, store food in glass or steel containers, and heat food in a glass or ceramic bowl covered with paper towel or a plate, instead of covering it with cling wrap or foil.
• Similarly, avoid plastic packaging. This is a key source of EDC intake for the average person, even from items like plastic water bottles and plastic cling wrap. Instead, invest in a glass water bottle and use beeswax wraps or glass containers wherever possible to wrap or store food.
• As a handy rule of thumb, remember that EDCs help make plastic flexible. So if you have flexible plastic containers, chances are they contain plenty of BPAs and should be avoided. Drink only from hard plastic bottles (even better if they’re glass or stainless steel) and avoid all thin plastic takeaway containers.
• When shopping for cosmetics, personal care products, bodywash, shampoos, conditioner etc, make sure to read the ingredients and choose products that don’t contain parabens.
• Be aware of marketing and misleading labelling. For example, products labelled “BPA-free” may contain BPS instead, which has similar endocrine-disrupting effects and negative health consequences even at low levels of consumption. Also, be sure to read labels and try to avoid food products containing additives, preservatives and anti-bacterial agents.
• Reduce your intake of processed, canned or packaged foods to minimise the EDCs you’re consuming from plastic wrapping, the lining of tins and cans, or cling wrap.
• Wash fresh produce like fruit and vegetables thoroughly to remove as many pesticides and other chemicals which might have been sprayed on them during farming. Even better, shop organic when buying fresh produce where possible, especially when buying items with thin or edible skins (it’s less important when buying thick-skinned produce, or items with skins which you discard, as the skin is usually the source of the majority of pesticides).
• Limit your intake of varieties of fish which may be rich in mercury, including tuna, swordfish, catfish, marlin and shark.
• Regularly open your windows at home to allow fresh air to flow through. Avoid using air fresheners, scented candles and heavily perfumed products in your home and space as much as you can, as these contain EDCs and can compromise your air quality.
• Look for “green” products when shopping for cleaning products, detergents, pesticides etc, as these use non-toxic substances in place of EDCs.
• Consider eliminating your perfume, or switching it for a natural alternative, as heavy scents can contain EDCs and harmful chemicals.

Want some more guidance on optimising your fertility and your chances of conceiving a healthy baby? Book a consultation with me today!