A small-scale University of California, San Francisco-led study has identified the first evidence in humans that exposure to bisphenol A (BPA) may compromise the quality of a woman’s eggs retrieved for in vitro fertilization (IVF). As blood levels of BPA in the women studied doubled, the percentage of eggs that fertilized normally declined by 50 percent, according to the research team.
The chemical BPA, which makes plastic hard and clear, has been used in many consumer products such as reusable water bottles. It also is found in epoxy resins, which form a protective lining inside metal food and beverage cans.
“While preliminary, the data indicate the negative effect of BPA on reproductive health and the importance of allocating more funding to further investigate why such environmental contaminants might be disrupting fertility potential,” said Victor Y. Fujimoto, MD, lead study author and professor in the UCSF Department of Obstetrics, Gynecology, and Reproductive Sciences, who also is on the faculty of the UCSF Center for Reproductive Health.
In the study, BPA levels and fertilization rates were analyzed for 26 women undergoing IVF during 2007 and 2008 at the UCSF Center for Reproductive Health. The women were a subgroup of a larger study evaluating the effect on reproductive health of trace exposures to toxic metals – mercury, cadmium and lead.
“Given the widespread nature of BPA exposure in the U.S., even a modest effect on reproduction is of substantial concern,” said Michael S. Bloom, PhD, senior author and an assistant professor in the departments of Environmental Health Sciences, and Epidemiology and Biostatistics at the School of Public Health of the University at Albany, State University of New York. The Centers for Disease Control and Prevention found BPA in the urine of nearly everyone tested in a 2004 analysis of the U.S. population.
BPA is gaining global attention as an environmental contaminant that impacts health owing to its widespread exposure and endocrine-disrupting properties, according to the researchers. An endocrine disruptor (also known as xenohormones) is a synthetic chemical that when absorbed into the body either mimics or blocks hormones and interferes with the body’s normal functions.
Previous studies in mouse models have indicated that BPA levels alter the DNA of eggs, and a 2010 study in humans demonstrated BPA urinary concentrations to be inversely associated with the number of eggs retrieved during an IVF cycle.
“Unfortunately, at this time there is no clinically-available test to determine BPA levels in women,” Fujimoto said. “Despite the limited evidence, a cautious approach for women who are considering IVF treatment would be to reduce their exposure to BPA through modifications in lifestyle and diet.”
We have known for some time that plastics (like those found in plastic water bottles) can mimic estrogen in the body, causing hormonal imbalances and affecting ovulation and overall fertility. But this is the first study I have seen that shows the link between BPAs, egg health, and egg DNA.
BPAs have also been linked to PCOS and Recurrent Miscarriages, and has shown to affect FSH levels in men as well. I also would not be surprised to hear that BPAs may have the same DNA damaging effect on sperm health as well.
Pesticides and herbicides have been blamed for the declining sperm count over the last 50 years. Did you know that herbicides and pesticides are also made from petroleum, the same raw ingredient used to manufacture BPA?
Here are some tips for avoiding BPA, leaching plastics, and herbicides and pesticides:
1. Stop drinking bottled water. The thin plastic bottle that the water is in leaches chemicals called xenohormones into the water. These xenohormones mimic estrogen in the body, causing there to be too much estrogen and not enough of the other important hormones (in men typically not enough testosterone to oppose the estrogen and in women not enough progesterone to oppose the estrogen). This in turn causes hormonal imbalance and fertility issues. While there are many toxins and pollutants that are xenohormones, bottled water seems to be one that everyone is exposing themselves to, purposefully, on a daily basis.
Some alternatives to drinking bottled water:
- Get a stainless steel or glass water bottle, or mason jars and fill them up at home.
- Be prepared; always have water with you.
- Buy water that is bottled in glass. “Mountain Springs” sells their water in glass bottles (the bottles are green); that is what we buy if we forget to bring our water with us.
2. Avoid plastics made with BPA and certain types of plastics for food. Plastics used for food storage usually have a number code on the bottom, which will tell you what type of plastic it is. According to The Green Guide, it is best to avoid:
- Plastic #3: Polyvinyl chloride (also known as PVC or vinyl), which is found in a wide range of products, including some plastic wraps and food containers.
- Plastic #6: Styrene, which is found in Styrofoam products, such as take-out containers, Styrofoam cups, and egg cartons.
- Plastic #7: Polycarbonate, which is found in some sport water bottles, some baby bottles, toddler drinking cups, and 5-gallon water bottles.
3. Avoid heating food in plastic containers or with plastic wrap (some plastic wraps are made with PVC). Heating increases the chances of harmful chemicals leaching out of plastic, especially with fatty foods. Use a paper towel or a glass or ceramic lid to cover food in the microwave.
4. Store food in containers made of glass, ceramic, or food-safe metal. If you do need to use plastic (it is almost impossible to avoid all plastic at this time in our society) choose plastics labeled #1 PETE, #2HDPE, #4LDPE or #5PP, which have lower potential health risks. If your community does not recycle these types of plastic, try to avoid them.
5. Avoid vinyl (PVC) shower curtains. Use curtains made of natural fibers, polyester or nylon instead. The heat from the shower causes the plastic shower curtains to leach chemicals, which are in turn inhaled by the bather.
6. Eat an organic fertility diet. Pesticides and herbicides have a negative impact on egg health, sperm health, and hormonal balance. The only way to avoid them is to eat organic. Some people say that organic is too expensive, but to me there is no choice. Please remember that these toxins will not only affect your fertility, but will also be passed on to your future child while you are pregnant and breastfeeding.
To help you get started on an organic diet here is a checklist and iPhone app that shares with you the produce that are MOST important to buy organic and the foods that are lowest in pesticides. All meats and dairy should be bought organic.
7. Cleanse the body and support the liver in getting rid of xenohormones and toxins. We cannot prevent the past exposures to these substances but you can help your body to get rid of them. Supporting the liver is a great first step as it is responsible for removing toxins from the body. Eating a healthy, clean fertility diet rich in fertility smoothies, greens, and fresh juices is another way to help the body to cleanse itself.
8. Protect and encourage egg and sperm health through diet, herbs and supplements. Preventing additional exposure to BPA, soft plastics, and pesticides and herbicides is a must, but so is nourishing, protecting and rebuilding from the inside. Diet plays a huge role as does antioxidants, which help to protect the DNA from damage.
Have you heard about BPA’s affecting fertility? What alternatives are you switching to?
- Bisphenol A. (n.d.). Retrieved from: https://medical-dictionary.thefreedictionary.com/Bisphenol A
- Fujimoto, Victor Y. et al. (n.d.) Serum unconjugated bisphenol A concentrations in women may adversely influence oocyte quality during in vitro fertilization. Fertility and Sterility , Volume 95 , Issue 5 , 1816 – 1819 Retrieved from: http://www.fertstert.org/article/S0015-0282(10)02794-9/fulltext
- Increased BPA Exposure Linked To Reduced Egg Quality In Women. (n.d.). Retrieved from: http://www.medicalnewstoday.com/releases/211721.php
- Bisphenol A – Toxic Plastics Chemical in Canned Food. (n.d.). Retrieved from: http://www.ewg.org/research/bisphenol