New Research: Persistent Organic Pollutants and Ovarian Reserve (Episode 635)

Full Transcript: Episode 635

Lisa: This is the Fertility Friday Podcast, episode number 635.

You can think of this week’s episode as a follow-up to last week’s episode. In last week’s episode, I shared a paper that was looking at the impact of endocrine disrupting chemicals on fertility. And particularly, we were focusing on female fertility, although there was a nod to male fertility. But in today’s episode, we’re taking it a step further.

The paper that we’re looking at today is specifically examining persistent organic pollutants and the size of ovarian reserve in reproductive age women. That is the title of the paper. And it’s actually looking at the potential impact of a particular class of chemical on the ovarian reserve itself. It’s kind of taking an even deeper dive into this question of does chemical exposure impact fertility? Without further ado, let’s go ahead and jump into today’s episode.

This study is looking specifically at this question of do certain classes of chemicals impact the ovarian reserve? This study does something different from the previous studies on this issue. It’s actually looking at ovarian reserve, and we’ll talk a little bit more about how it’s doing that. Basically, they took 145 pregnant women who were undergoing elective C-sections, and they did that so that they could have access to ovarian tissue so that they could actually look at the ovarian reserve in more of a significant way.

For those of you who are longtime listeners of the podcast, who are kind of familiar with all of these topics, the ovarian reserve, when we look at ovarian reserve testing or when AMH is being tested, or when we’re looking at some of those types of tests, those are always indirect measures of the ovarian reserve because we can’t really go in and take out an ovary and dissect it and find out how many eggs are left, like count them. This study, while they’re not doing that, they’re not taking out an entire ovary and doing a count, they are getting more of a representative sample of ovarian reserve, and that allows them to actually examine this question of could these chemical exposures be impacting ovarian reserve.

There’s a lot of really interesting results and takeaways from this paper. As I mentioned, these researchers took a bit of a different approach by trying to make a direct measurement of ovarian reserve, which is not something that is typically done. What the researchers were doing is that they were actually counting follicles in biopsied ovarian tissues.

These women who were pregnant in the study, who were planning to undergo an elective C-section, they measured 31 persistent organic pollutants in their blood, and they were trying to find out whether these chemicals that are essentially banned, these industrial chemicals, flame retardants, and other types of chemicals, if these chemicals are specifically associated with fewer follicles in the ovary. During the elective cesarean section, after the baby and placenta were delivered, they took a small sample from one ovary. They had their own procedure for how they’re doing that.

When I was reading this information, there’s, of course, a part of me that’s thinking, is this a good idea? Does this have a negative impact on the ovary? Based on what they’re saying, because they took a very small amount, it likely has minimal effect, but who knows? I just thought I would mention that in case any of you are wondering how could they actually test this. It’s still not giving us the kind of count, but it is useful to know that they were actually trying to get more of a representative idea of does this affect the reserve.

One of the first points I think that the paper really highlighted, just because of its design and what it was intended to do, is that the researchers did determine that these what they’re calling legacy pesticides, and industrial chemicals were associated with fewer dominant follicles. When they did do these biopsies and they did identify the concentration of these chemicals in the women in the study, the women who had the highest levels of these chemicals, essentially their ovarian reserve count was lower.

There’s certainly a couple, many, many things that are disturbing about this. One of the disturbing pieces of it is that this is why these chemicals are often referred to as persistent organic pollutants, because these chemicals, many of them are not allowed to continue to be in the supply, whether they are or not is another question. But a lot of these chemicals have been banned, and that’s why they’re calling them legacy chemicals, but they still are present. When they do studies, we still have these chemicals in our bloodstream. That’s obviously something that is disturbing.

In particular, when they did this testing, they did find this link. Women who had the higher levels of these chemicals, they did find that the ovarian reserve was lower. I think one of the other findings that they had was that this didn’t mean that the AMH levels in these women were lower. It was having an impact on the ovarian reserve, but not necessarily an impact on the AMH number. So what this shows is that a person could have an AMH level within the range, and that wouldn’t necessarily be giving any information that these chemicals could have had a negative impact on the reserve. The AMH numbers were, in this study at least, independent of the actual impact that these chemicals were having on the reserve.

The AMH levels, the number that most women and practitioners look at when assessing ovarian reserve, although it may be reflecting the growing follicles, it’s not necessarily directly showing the dominant reserve. What they’re saying is that dominant reserve is what the chemicals appear to be targeting. Really interesting information, again, also very disturbing. These chemicals are essentially, or have the potential, or what they’re showing is that they are likely directly impacting the reserve. There’s serious implications there for fertility.

There was a couple of other points that really stood out in this paper. A second one was what they called the cocktail effect. What’s interesting about research, if you read a lot of research, in order to conduct a study, you typically have to, if you’re studying certain chemicals, you have to study chemicals kind of one at a time often. If you were to actually try to determine is this chemical causing this effect, you have to isolate that chemical and then study it, or you have to search the bloodstreams and kind of isolate what type of chemicals that you’re finding.

Either way, I would say that it’s always a limitation in research because you’re trying to isolate a variable and you’re trying to determine if this variable has these effects. But in the real world, when we’re living our lives, no one’s exposed to only one chemical. This presents obviously an issue. We can learn what we can learn about that individual chemical, or these 10 individual chemicals, or whatever, but then in the real world, you’re exposed to many chemicals. What happens when you have multiple chemicals in your bloodstream? Do they have a different effect when they are together in the chemical soup? Or are we just looking at the effects of them independently?

This is a long way of saying that in this particular study, they did have the opportunity to look at what happened when certain chemicals were presenting together. What they found was that there were different results when certain groups of chemicals were together versus when they were apart. The researchers said that, of course, this could suggest that certain chemicals are more harmful when they’re together versus when they’re separate. What they found was that a combination of flame retardant, a certain metabolite of DDT, and a certain PCB were associated with fewer dormant follicles. When they put these chemicals together, it had an even higher negative impact on the ovarian reserve.

None of this is good news, but it’s not necessarily surprising either. If you just take a moment to think about it, we don’t know what happens when you mix a whole bunch of different chemicals together. But we do know that we have a lot of different chemical exposures in the world. This does give us that additional data that when they’re combined, there could be other effects.

At the end of the day, when I think about these things, I feel like there’s very little that we know about them, even with all the research on these individual chemicals and what they could be doing. That’s not representative of how we experience them in the world. It’s not like you only have pesticide exposure. If you’re eating food, if you’re going outside and breathing air, if you’re using different chemicals and different products on your body, then you are being exposed to pesticides, and then you are being exposed to phthalates, and you are being exposed to all these different things. We don’t really know what happens when you have all of those things together and they’re being exposed. I just want to stress that when I talk about toxins, it immediately feels very scary and overwhelming. Stick with me here.

This reality, because at the end of the day, we’re all living in this world, and we all have some level of toxic exposure. The goal of talking about these things isn’t to try to really freak us out, but it’s just to help us to become more aware of it, to learn about some of the effects that it may have on fertility. Then also to help motivate us to aim for reduction, so that the goal isn’t to be perfect and totally clean, but we can just try to think about ways that we can reduce, and also ways that we can support our body’s detoxification pathways. I’ll just kind of leave that right there so that we don’t get too in the weeds about it.

Moving on to another point, and I feel like this was something that came up in last week’s episode, and it’s already kind of permeating through this week’s episode, which is that clearly, though some of these chemicals are banned, that doesn’t mean that they are gone because they’re still showing up in research. Even though many of these chemicals, there’s regulations now, they’re not supposed to be used anymore. When they do these studies, they’re still showing up in our bloodstream. Again, that’s why we’re calling them persistent organic pollutants.

Of the 31 chemicals that they were testing for, they found 14 out of the 31 in every woman. 45% of these chemicals that they were looking for were found in every single woman, demonstrating that extensive mixture exposure to persistent industrial chemicals is common among pregnant women. That was a quote from them. Basically, they’re saying that, yes, these chemicals have been banned. But when we test for them, the fact that so many of them are still present in the serum blood levels of pregnant women shows us that they’re kind of still there, and they’re definitely not going anywhere.

This tells us a few different things. One of them, it does show us that these chemicals are kind of in our bodies, that as women, we’re bearing a lot of this toxic load. The researchers did note that American women had higher levels of these toxins than Swedish women. I’m not sure that they have an exact reason for that. The exposure levels certainly would be related to how much of these chemicals were used when they were in their full swing, depending on what part of the world that you live in. It does suggest that North American women may have a higher burden of some of these chemicals compared to other places in the world. Nevertheless, it is certainly eye-opening.

Link then between these chemicals and infertility or fertility challenges, because of how they conducted the study, it does suggest that the link could be, to how these chemicals impact the ovarian reserve, specifically how they’re impacting the follicle development within the ovary itself. One of the things that the researchers point out is that when women have high levels, and you could say women and men, but when women have high levels of these persistent organic pollutants in their bloodstream, this is associated with a longer time to pregnancy and higher infertility rates.

This study is kind of providing a potential explanation by saying that it could be actually having a negative impact on the follicle pool. As women, we are all born with all the follicles that we’ll ever have. When we are babies coming out of our mothers, we actually already have this pool that’s there. This research is saying that these chemicals could be having a negative impact on that pool. But it goes potentially deeper than that, because when you were in your mother, you already had the follicles, all the follicles that you were going to have.

As women, when our mothers are carrying us, we already have those follicles in our ovaries. If our mothers are exposed to certain chemicals, it could have an impact on their reserve. But by proxy, it could theoretically have an impact on our reserve as well. As a mom, when we are pregnant, and we’re carrying our daughters, our level of chemical exposure could be impacting our daughter’s ovarian reserve. That is a whole other level of how this type of exposure could affect not only us, but generations.

When we get into this, is why when we get into the toxin conversation, it could definitely result in some spiraling if you’re not careful. I’m not laughing at this. I’m certainly not saying that it’s not serious. I’m just pointing out that it’s really important to look at this data, but also with a level head, and just recognize that we’re all exposed to this. This is affecting everybody to some degree. We can’t completely avoid exposure or anything like that. The first step is always to learn a little bit more about it and learn about the implications.

It certainly is terrifying in that sense to think that there could be effects even beyond us to our daughters if we happen to have higher levels of these chemicals. It could be that it’s not just that we’re having struggles conceiving, or that it’s taking longer, or that it’s having a negative impact on our follicle pool, but it could potentially be affecting our daughters as well. Certainly something to think about. It’ll be interesting in the future years to see where additional research comes into play with regards to this topic.

One last point. This was a point that I did bring up in a different way in last week’s episode. There are decades of sperm studies. This study represents the first what we could call follicular tissue study. This was a very unique study in that they actually did find a way to collect tissue from the ovaries and actually look at the follicles, so that they could have that representation of what’s happening in the ovarian reserve. This is essentially the first study of its kind, where when it comes to sperm research, we have decades, many, many years of research on that.

As we know, it’s easier to study sperm because it doesn’t involve targeting a specific population of women who are having elective C-sections so we can have access to the ovaries. From a practical standpoint, it’s obviously more difficult to conduct research like this. It certainly is even incredible that they were able to do it. It certainly does point out a very important piece of this puzzle, which is that we don’t even know as much as we need to know about how these chemicals could be impacting female fertility, because we have far less research on the topic. We have far more research on how these chemicals impact male fertility. But with that said, it is encouraging to see that this research is taking place, and that there’s more of an interest in looking at the impact specifically on female fertility.

Infertility rates are rising, with one out of every six couples experiencing infertility. That puts the rate at about 15%. Millions of couples around the world are in this category and struggling, or taking longer to conceive, or whatever the case is. Certainly there is a need to be looking deeper into these topics.

I would say, again, the biggest takeaways I have from this paper, if I were to summarize, is that the research continues to show that there is a link between these chemicals and fertility, these chemicals and the menstrual cycle, these chemicals and our hormones. The more they look at it, the more specific they can get at how it’s impacting. It is terrifying to think that these chemicals could have a negative impact on ovarian reserve, and that impact could be even generational. It just further shows us the importance of doing what we can to reduce our exposure.

Of course, this is a bigger issue, because no one is drinking persistent organic pollutants. These chemicals have already been banned, but they are still there. There is a certain level of unfairness to this conversation and this question, because there’s a certain level of exposure that is completely not up to us. It’s just based on where we live, what environment we’re in.

With that said, if you are passionate about this topic of toxicity, if this is something that you’re interested in, we will make sure to link in the show notes page some of our other episodes where we’ve covered this same issue. I would also encourage you to grab a copy of Real Food for Fertility and read the toxins chapter. Not only are we providing you a lot more of the scientific information about the different chemical classes, but we are also talking about ways to minimize your exposure, and also ways to support your body’s detoxification pathways, so that if you have been exposed or are exposed to these chemicals, that at least you can start working on helping to get some of these toxins out.

There are ways not only to reduce your exposure, but also to start to excrete and remove some of these, especially if you are planning to conceive. It is a really good idea to actually spend some time getting some of the stuff out of your body, because as I mentioned in the previous episode, it’s well known that when women are pregnant, if they do have toxin exposure, they’re dumping it. That’s a terrible word to say, but that’s what it is. The baby does take on a lot of those chemicals. That’s how our body’s getting rid of some of these chemicals. That could be one of the reasons why these persistent organic pollutants are still showing up in populations, even many years after they’ve been banned. It could be because we’re passing them on to our kids.

Lots to think about. The toxin conversation is always a heavy one, but an important one to talk about, and just continue to learn more about it, minimize exposure, and find ways to support our body’s detoxification pathways.

With that said, I hope you have a wonderful week weekend, whenever you’re tuning into the show. If you found today’s episode helpful, and you can think of somebody who would benefit from hearing it, then feel free to share this episode. You can always head over to fertilityfriday.com and find the show notes page. You’ll find it there on the website. You’ll also find the paper that we talked about and related episodes and all of that, those good details. Make sure to head over there if you’re listening in your favorite podcast player, you’ll also find the link in your favorite podcast player right there. Again, have an amazing day. As always, until next time, be well and happy charting.