Is PMS Disrupting Your Sleep? | FAMM Research Series (Episode 584)

Full Transcript: Episode 584

Lisa Hendrickson-Jack:

In today’s episode, we are looking at the potential connection between sleep disturbances and the menstrual cycle. More specifically, the likelihood of increased sleep disturbances when you are approaching your period or around menstruation. So we are delving into a study that looked at just that. They measured sleep patterns across the menstrual cycle and they came to some interesting conclusions. As usual, we are going to talk about some of the strengths and the implications of the study as well as some of the potential drawbacks. And of course, I’ll be looking at how they determined the different phases of the menstrual cycle and how they drew their conclusions about it. So without further ado, let’s go ahead and jump into today’s newest FAM research series episode.

So the paper that we are diving into today is called The Interaction of Sleep and Emotion Across the Menstrual Cycle. And, of course, it’s always fantastic when we’re seeing this type of research being done. This is actually a newer study that was recently released in the Journal of Sleep Research. And of course, the researchers are trying to see if there is a pattern of disrupted sleep across the menstrual cycle. And one of the reasons why this is a topic of interest, I mean, the researchers talked through a few different reasons why they were interested to study this. One is that women do tend to experience disrupted sleep more commonly than men. They certainly have a higher instance of insomnia and that is thought to be related to the sex differences between men and women and so they’re looking at that for that perspective and they’re also trying to determine if there is a relationship between how these sleep disruptions are happening and the menstrual cycle itself. So that’s a little bit of background, and essentially what they did, the way that they designed this study, is that they had women, of course, they didn’t have them track and chart their menstrual cycles, but they determined what phase of the menstrual cycle they were in based on their self-reporting of when their periods happened, so when the onset of menstrual bleeding took place, and they also had the women test their LH levels. And this is very standard. This is typically how ovulation is identified in research. Of course, I’ve spoken about this many times. And I think that part of the reason they do this as well is just due to budgetary limitations when you’re dealing with the logistics of setting up a study. I think that they’re looking for the ways that they can test these things that are the least invasive and least time-consuming especially to get people to participate. So I do think there are some reasons why they do it this way. So I mean, the good thing is that they actually have these markers. So they are able to identify the period of time that they were looking at. So they were specifically looking at the kind of three-day period leading up to your period plus the first three days of menstruation. So they were looking at that specific phase to see if there were cycle disruptions related to the menstrual cycle there. And in terms of confirming ovulation, looking at luteal phase length, although they discussed the potential role of hormonal fluctuations, the potential role of estrogen and progesterone in sleep disruptions, they didn’t specifically measure those hormone levels. So we’ll get into a little bit more of the potential implications there. That’s how they were identifying where these women were in their cycle. And then to identify if there were any sleep disruptions, they tracked that in two specific ways, which I think was really interesting. So they had the women wear a wrist device that was measuring their sleep. And so this is a validated way to kind of measure the different stages of sleep. And so I thought that was interesting that they did that in a very specific way. And then they also had the women note down in their diary, like so they had them keep a journal of their self-reported sleep disturbances. So that was interesting as well to compare their subjective experience of their sleep experience to the actual data that was kind of given by this wrist device that was attached to an app. So I think that that’s really interesting. And they didn’t measure a ton of other details. They measured mood, so they were looking at different emotional fluctuations as well, but that was kind of their main measure. So what did they find? What were the findings of their study? So as I mentioned, they did measure the sleep in two different ways, and so during that perimenstrual phase, so the three days leading up to the menstrual period plus the first three days of the period. The self-reported data, so the women wrote in their diaries, significantly increased disrupted sleep. And they measured this by a measure they called total wake time. So they’re looking at their wake during the middle of the night or what’s going on. And so the women self-reported about eight to sixteen minutes more awake time during that specific phase of the cycle overall. And interestingly, when they looked at the wrist data only, so the more objective measure of it, they found that the total wake time was also significantly higher, but it was four to seven minutes. So that is a really interesting finding, and the researchers commented on that — when they’re experiencing it to be basically double, twice or even more. The women are experiencing and self-reporting double the actual time that they were awake based on the objective measure of the wrist tracking device. So I thought that that was really interesting. And when they looked at mood, there were significant mood changes around that time as well. And positive mood dropped when the total wake time increased. So when the women’s sleep was more disrupted, that affected their mood. And one of the things that they said was kind of the most significant mood change that they found was that women were kind of reporting higher levels of anger and frustration and irritability around that time. So that is really interesting. And I think that the researchers looked at that, they found this correlation, and then their question is, well, how significant is it? What does it mean that there is this difference between how they experienced it and what the kind of more objective data showed? And they also talked a little bit about, in general, there is an increased correlation of even other emotional or psychological issues when women are experiencing insomnia or disrupted sleep. Those other conditions worsen as well, so they do know that this can be a really significant challenge.

I feel that these results aren’t necessarily surprising. I think that we know that there’s a variety of different things that can change around that phase of the cycle. One comment that I want to make, well, several, but one of the interesting observations that I’ve made when looking at PMS research is I do feel that assumptions are made about why these things are happening or assumptions in general. Of course, I do feel that they’re not necessarily looking deep enough into this issue to draw meaningful conclusions. Let me explain what I mean by that. When looking at the research, and this is about, I would say this carries over into hormone research in general, estrogen tends to be the focus. And when this is something that Dr. Jerilynn Prior has pointed out, I’ve interviewed her a few times on the show, and Dr. Prior has been studying and increasing the research literature and curiosity around progesterone for decades because the research often tends to be estrogen-focused. They’ll look at the correlation between estrogen and bone density or estrogen and a variety of different things, but they’re not necessarily focused on progesterone so much. So in this, there was a couple of things that the researchers said in here that I thought were really interesting. And this is based on research, but again, I just don’t know if this is a true conclusion that can be made. So I’m just going to look for these couple of quotes that I found here. So one thing that I thought was a really interesting statement, and again like where is this coming from? So they said increased progesterone is thought to initiate a rise in core body temperature disrupting sleep, which I think even just that is interesting because they’re saying it’s thought to. It does. You can measure it. You could just take the BBT, right? So anyways, so that’s what they say. And they say progesterone is associated with nearly one degree Fahrenheit increase in core body temperature, which may contribute to sleep fragmentation. So this is when I was in university and went into my statistics classes, the university level statistics classes. One of the things that they would say over and over again is correlation doesn’t equal causation. And so what that means is when you see two parameters that are associated with each other, you can’t just automatically assume that one causes the other. And this to me is just bizarre that they’re saying that — okay, so because progesterone increases in the luteal phase, that’s the reason why the sleep is disrupted. What? And especially when you’re looking at issues around the kind of premenstrual syndrome conversation. Again, if that was true, then if we looked at the luteal phase, so for anyone who is a little bit new to this, the first day of your cycle would be the first day of your menstrual period, and then once you move into that premenstrual phase, that is characterized by follicular development. That’s why we’re often calling that preovulatory phase the follicular phase. And as the ovarian follicles are developing, they’re producing significant estrogen. So the estrogen would be highest several days prior to ovulation because ultimately that peak in estrogen levels is what triggers the LH surge, the surge of luteinizing hormone that ultimately triggers ovulation. So we have estrogen reaching its peak shortly before ovulation, and then estrogen dips a bit, but estrogen is still fairly strong in the post-ovulatory phase. After ovulation is the only time we’re making significant progesterone, and in a healthy cycle, your luteal phase, so the second half, the post-ovulatory phase of the cycle would be anywhere from 12 to 14 days long, typically in a healthy cycle. And when we’re looking at the rise and fall of progesterone in a healthy cycle, you would actually have a significant rise in progesterone that would peak mid-luteal. So around seven days after ovulation, the progesterone would be highest. So to kind of call this interesting conclusion that we’re just throwing two pieces of data that are correlated together and saying one causes the other — if the progesterone was directly responsible for the sleep disruptions, we would expect then the majority of the sleep disruptions to be in the mid-luteal part, right? We would expect that to happen in the middle of the luteal phase when progesterone is highest if it has such a destabilizing effect. But interestingly with PMS, what we see is that it’s during that week leading up to the menstrual period when we’re seeing, whether it’s classic symptoms of PMS, increased depression, anxiety, or we’re seeing carbohydrate cravings or bloating or a variety of different, some of those different factors, we tend to see those increased during the days leading up to the period. And that would be when progesterone is dropping, right? Not when it’s the highest. So I would kind of add to that conversation and say that without a solid understanding of the menstrual cycle, we’re coming to these conclusions that don’t even necessarily make sense when we look at what’s happening from a biological and physiological perspective. So if, as what they’re saying is, progesterone is associated with this increase in temperature, and so therefore, because the temperature is higher, it’s also causing sleep disruptions — if that was the case, then like I said, we would expect those sleep disruptions to be more consistently mid-luteal when the progesterone is highest. But that’s not what we see.

So based on the research, and if you’re tracking women’s menstrual cycles, one of the key things I feel like is missing from these discussions around PMS is that every single woman doesn’t experience PMS in the same way. There are some women that experience moderate to severe PMS. There’s some women whose symptoms are so severe that they border on PMDD or enter straight into PMDD territory, premenstrual disorder. And in that situation, that is a really exacerbated version of PMS that results in a significant disruption to your day-to-day life. So these are women who are finding it difficult to actually participate in life, to go to work for several days every cycle, related to their intense PMS symptoms. Whereas other women have very mild symptoms, if any at all, that don’t affect their daily life whatsoever. So one of the things I find interesting about PMS research is that it’s almost assumed that this is just a woman thing, and we’re not looking at what are the differences between women who have these symptoms and women who do not. And then even if they test those types of scenarios, they’re often not testing hormone levels either at all, as in this study. They didn’t look at progesterone and estrogen levels. They didn’t track to see if there were differences between women. They were just looking for general trends of sleep disruptions and making those correlations, which is fine. It still gives us some information, but I would obviously want to take this deeper and I would want to know, okay, so based on all the women in the study, how severely were these issues? Were there women that had little sleep disruption? Were there women that had a lot of sleep disruption? And what were the differences in hormone levels? What were the differences in luteal phase length, menstrual cycle length, other PMS symptoms across the menstrual cycle and between these women depending on the severity of the sleep disruption, because then we can actually have a meaningful conversation of what is potentially driving it. And of course, my hypothesis would be that it’s not progesterone causing it because that makes no sense, as I explained already. What potentially could be causing it would be the significant drop in progesterone before it’s supposed to. So essentially a luteal phase issue, luteal phase defect, or a sharp drop in progesterone or significantly lower progesterone relative to estrogen. Is there a difference between the overall progesterone levels between women who are experiencing these symptoms versus who are not? And you wouldn’t be able to gather that information by simply testing progesterone once or something like that. You would actually have to have these women come in every other day or every three days and actually spot test those levels, those hormone levels throughout the cycle. And you’d have to more specifically clarify and confirm ovulation, identify ovulation, whether it’s with the basal body temperature testing, whether it’s with progesterone testing, but to be a lot more specific as to identify that ovulation day and then kind of tease out the hormonal fluctuations throughout the cycle. Of course, this is not what was done here.

So I’m just pointing this out. I’m critical of research, especially menstrual cycle research, because I feel like this kind of worldwide overall lack of information about the menstrual cycle and how it works and the hormones and the lack of appreciation for just fertility awareness techniques for tracking and understanding the different phases of the cycle and the different parameters and factors. I feel like that lack of information results in research that, again, it’s good to have any research. It’s good that we have this data that we can build upon, but I feel that it just shows in the poor design of these studies. And like I said, that particular comment I found really interesting. It’s like, oh, so just because progesterone raises temperature, we’re going to say that that causes sleep disruptions when not all women have that. We’re not going to look at that. Maybe as women, our bodies aren’t just naturally flawed, right? And progesterone just causes us to not be able to sleep. And maybe our bodies are fine, but it’s when the cycle isn’t functioning normally, when the hormones are imbalanced. Maybe that’s when we see the issues. But of course, that’s not what their hypothesis was. And one other thing I thought was really interesting, so this is another quote from the paper. So they were talking about the changes in hormones and the sex differences between men and women and trying to hypothesize why we might be seeing these changes in sleep patterns around that time. They say, “Although these complex relationships are poorly understood,” so they’re acknowledging that they’re poorly understood, “evidence suggests estrogen has positive effects on mood and cognition. Conversely, progesterone is associated with more negative mood, for example, irritability and depression.” So again, I think that that’s such a surface level analysis of what’s going on. So we have two phases of the menstrual cycle, the first half and the second half. We’ve got the pre-ovulatory phase and the post. And the pre-ovulatory phase is characterized by higher levels of estrogen. And the post-ovulatory phase, it’s not devoid of estrogen. It’s just the levels are a bit lower. And then progesterone obviously is quite significant, and we only produce significant amounts post-ovulation. When they’re looking at mood changes throughout the menstrual cycle, since women typically have more neutral moods in terms of their reporting around ovulation when estrogen is higher, and since their mood tends to change and be more poor — even in this study, there was a higher rate of reported anger, frustration, irritability during that post-ovulatory late luteal phase shift — they’re just saying, “Well, progesterone just causes poor mood.” And I feel like that’s really interesting because progesterone has a calming effect. And again, the issue isn’t that progesterone is causing women to have a poor mood. The issue is that when we have an imbalance of hormones in that late luteal phase, when we have too little progesterone, that is what is actually associated with the mood changes and the increased PMS symptoms. But we’re not looking at the nuances. We’re not looking deeply into it. We’re just making these broad sweeping conclusions like, well, these two things are correlated, so one must have caused the other. So those are a couple of my critiques of this paper. But I think again, the good thing is that this research is being done. The good thing is that now we have more researchers paying attention to some of these shifts. And of course, that’s a good thing, but when you are missing that nuanced perspective, when you’re missing that deeper understanding of not just the fact that women make estrogen and progesterone at different times of the cycle and just kind of throwing this in as, and so therefore that causes all the problems across all women, looking at the between-women differences, right? Looking at that. And what I’m finding when I’m looking at PMS-related research is even when they do look at potential hormone differences between women, they’re not, again, looking at the nuance. They’re potentially taking one spot check of progesterone or estrogen once per cycle. So imagine doing a study and trying to determine whether or not the fluctuations of progesterone or the levels of progesterone versus estrogen are contributing to these symptoms, but literally in the course of an entire 29-day menstrual cycle on average, we’re going to spot test for estrogen once, and we’re going to spot test for progesterone once in the whole cycle, and then draw a conclusion that if those levels are not necessarily what we thought they would be or if they’re similar, that there’s no differences. So I think for future research, I mean, I would love to be in charge because I think I could design some interesting studies or at least come up with some new standards for testing hormones before researchers are making all these comments about the hormones. But to actually get more meaningful information, we would really have to not only test in this general way about the menstrual cycle, but I think if we really wanted to know — if there was enough curiosity and enough concern that we really wanted to understand what was happening with women and we really wanted to understand the menstrual cycle — then we would actually have to take the time to understand the menstrual cycle. And we would also have to take the time and care to accurately identify ovulation using the LH strips, fine, but also correlating with other data, considering doing the morning temperature data. And interestingly, we do have a lot of different devices now. So women can wear wearable devices to measure their temperature, and they can correlate that with the LH testing, and that’s not as energy-intensive as it once was. While it may not be the most perfect measure, it would still be a step up to be able to correlate the LH testing with the wearable temperature device in a research setting. That would make a lot of sense to me. And also to do hormone testing. And again, now there are a lot of different companies that are coming up with at-home hormone testing options. So I do think that while at one stage in the research world, this would have been very cumbersome for the participants to be going in and being clinically tested on a daily basis. So there’s certainly an argument to be had for making the research design something that people are actually likely to do and to complete. But with that said, I think we have to balance that with what are we trying to do here? Are we just trying to give lip service to these things and touch on the most basic surface level understanding of these changes? Or are we wanting to really know what the role is of the hormones, the menstrual cycle, and to really understand what’s at the root of this? And that’s a whole question I don’t think we have the answer to, because if we do determine that it’s not just an inherent problem with females as a whole sex category, and we do determine that some women are fine because their hormone levels are optimal and other women are not fine because they have this imbalance of hormones — and we go beyond, especially when it comes to issues of whether it’s sleep dysregulation or whether it’s emotional or mood dysregulation, whether it’s issues such as depression or other psychological or psychiatric conditions — if we actually look at this potential hormone component in there, that could have a ripple effect where we are less reliant on psychiatric medication if women actually improve their symptoms by simply balancing their hormones. So there are potential implications for an entire industry of pharmaceutical drugs that may not actually want us to come to those conclusions.

So I guess it’s just to be seen. Is this research — this lack of research rigor, this poor design — and it’s a theme. For anybody who reads research a lot, you can see this theme. Anytime we’re looking at menstrual research, I’ve talked about it for years now in my FAM research series where we’re looking deeply into the research. The way that they look at menstrual cycle parameters, it’s just not specific enough. I would say it’s a poor design. It’s a good start. It’s certainly a good start, but I’m recording this in 2025. I feel like we could do better, and especially with the advent of all of these new technologies that make it easier. All these different tracking devices, the whole world of FemTech. They’re wanting to make it easier for us to test our hormones at home. I get DMs on a daily basis from new companies that pop up all the time. I’m pretty narrow as to what I share on the podcast. I want to make sure that I’m not presenting information to you that I haven’t had a chance to vet. But what I’m telling you is that there’s a huge industry now of all of these different tech tools and different ways of measuring hormones. All things female hormones, there are devices and tools for that now. So there’s not as much of an excuse as even 10 years ago in terms of how difficult this might have been to implement with research study participants. I think that we’ve crossed that bridge and it’s a little bit easier now.

So in conclusion, this was a really interesting study. I think the takeaways for us are that we can see with the data that the menstrual cycle does play a role in a variety of different aspects of our lives. I wouldn’t conclude that inherently with the menstrual cycle, it’s going to disrupt sleep and it’s going to cause you to have severe PMS symptoms and this is just normal and this is just hormonal and this is just a part of being a woman. Based on what I’ve talked about so far, it should be clear that what I’m talking about is if we look at our menstrual cycle as a vital sign and we understand that there are normal parameters, then we would want to look deeper. And we would want to find out the differences between women who have these moderate to severe symptoms, women who are experiencing greater disrupted sleep around the time of menstruation, leading up to menstruation and shortly after. And we would want to find out definitively if there is a hormone component and not just by spot testing once in the cycle or not testing the hormones at all and drawing random conclusions about how progesterone just causes sleep disturbance because it’s associated with an increased temperature — which makes no sense. We would actually look at that scientifically. We would take the progesterone testing and spot test her every other day or every three days throughout her cycle and compare that data across women. We could plot her progesterone on a graph to determine if her progesterone curve is normal, or if she’s experiencing a sharp drop in progesterone that correlates with her symptoms. And if we have that level of data, then we can draw meaningful conclusions about why some women are experiencing these sleep disruptions and why they are not, instead of just making all these assumptions that the menstrual cycle just is like this and this is just something that happens to all women when we know that it doesn’t. So while I am happy that they are doing this research, I certainly think that there’s room for improvement. And I know that there are a lot of women’s health professionals and researchers that tune in to these episodes. So I am always hoping that this information will kind of have a ripple effect and the quality of research will be better. And for those of you who tune into this episode but never thought about it this way, for those of you who have read certain research like this or are interested to learn more about it, or for those of you who may even be in the field of research and are currently doing your graduate studies or PhD level studies, these are legitimate questions. And sure, it can be challenging to get funding, I’m sure. And to design a study that is this in depth, I’m sure it would be difficult, potentially more difficult to have participants follow through, because that’s a significant issue in all research studies. In this study, they had such a significant number of participants who initially said yes, but in terms of the actual data that they could use afterwards, it’s a much smaller number. But this is an inherent challenge in all research. So hopefully I’ve given you lots to think about in this. And I think that when you don’t assume that the menstrual cycle is inherently problematic and all of these issues that women experience are just a part of being a woman — when you start to understand that these are symptoms of potentially an imbalance or things that could be rectified, and when we have a structure and way to actually look at the cycle, to track what’s happening, to start improving some of what we call in FAM our foundational factors and start to see those improvements — then it really gives us hope and it gives us a plan and a structure for how to improve our day-to-day experiences instead of feeling like we are just subject to these things, instead of just being told it’s in our head or it’s not a big deal, or feeling like, well, it’s just like this because this is what happens when I have my period and there’s nothing I can do. I feel like it really gives us not only hope, but a specific strategy.

So let’s see what happens in the next few years. Let’s see what happens in this field of research around menstruation. I’m really curious to see if it will improve, and if I ever have the opportunity to participate in research studies or study design, I would certainly be putting in my two cents, although I’m not sure if my paper would be flagged or if it would actually be published if that ever happened. So, with that said, I hope you have a wonderful weekend whenever you’re tuning into the show. If you enjoyed today’s episode and you can think of someone who would benefit from hearing it — you have a friend who you know has been struggling with sleep issues. Now, one thing I’ll say as well is that we did not talk about issues specifically related to the perimenopause phase today. This was more of a general study. They actually excluded women who were over the age of 35. So the participants in the study were specifically from ages 18 to 35. So that would be another interesting conversation. And what I’ll leave you with — my thought on that is that when we are in that perimenopause phase, the 10 years leading up to our last period, typically in our early to mid-40s, then this is a time when we are gradually starting to wind down and gear towards our final ovulation. And it becomes harder to produce significant progesterone. Our bodies are a lot more sensitive during that time to the insults that can impair our optimal progesterone production. And so I’m not of the opinion that as women, we’re just designed incorrectly and that all of the symptoms that women experience during that phase are just inherent, normal. I do think that to some degree, when a woman has greater symptoms, more significant symptoms, we could in the same way look at what is the difference. And these are the questions I would love to see asked more often instead of looking at perimenopause as every woman’s having this horrible experience. That’s not true. If you dig deep enough, there are some women who have mild symptoms during that phase. And so the research I would like to see is to compare the women who are having these really challenging experiences, significant sleep disruptions during that period of time, versus women who are having very mild symptoms and are not having these challenges, and see if we can find differences hormonally so that we can get a better understanding, instead of assuming that it’s just this issue with all women. We can actually look at who’s suffering and compare them to who’s not and see what the differences are. So I have a lot more curiosity about that and I’m sure as I get closer into those phases, I’ll have a whole lot more to say. So enjoy the rest of your day. And if you’re wanting to share this episode, FertilityFriday.com/584 is the share link. Again, that’s FertilityFriday.com/584. And with that said, have a wonderful weekend whenever you’re tuning into the show. And of course, as always, until next time, be well and happy charting.