The Period Brain: Understanding Progesterone and Its Impact on Women’s Health | Ep. 593

Episode 593

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This is the Fertility Friday podcast, episode number 593.
I’m so excited to welcome Sarah Hill back to the podcast today. In today’s episode,
we are talking about her new book, The Period Brain, and it is absolutely not just
another period book. She delves into the science and really important issues,
as we’ll touch on in today’s episode, behind why women tend to feel so bad for
half of the cycle. I certainly have a lot to say about that, but what I found
most fascinating about Sarah’s book is her deep dive into the science and the way
research is done, specifically the differences between men and women and how they’re
not taken into account when they do the research. So she really dives into some
fascinating details for where our research is lacking and how far behind women have
fallen just because of the lack of accurate research on women. And that applies to
all different areas from the drugs that are approved on the market to even just
basic understanding about how our bodies work. So I feel like this interview provides
a much needed explanation for why, as women, we often feel so misunderstood,
why we often feel that our healthcare providers are not prepared to support us and
I think it’s really validating. It doesn’t make it easier though, because it still
means that we are misunderstood and we are underrepresented in the research. And it
does mean that there are many situations where our healthcare providers aren’t
necessarily able to support us because literally the research isn’t even there. So
with that said, before we jump into today’s interview, I’m going to quickly share a
little bit about Dr. Sarah E. Hill. She is an award -winning researcher, professor,
and author of “This Is Your Brain on Birth Control,” which changed the national
conversation about women’s hormones and the birth control pill. And her new book,
“The Period Brain,” is due out in September. So let’s go ahead and jump into
today’s interview with Dr. Sarah Hill. Well, without further ado, I’m so excited to
welcome Dr. Sarah Hill back to the podcast. Welcome back to the show. Thank you so
much for having me back. Well, I’m so excited to have you. And we were just
talking about how much has happened since we last spoke. And of course,
your new book, I mean, I reached out to you. I was so excited about this topic,
because I feel like it’s a topic that hasn’t really been addressed well.
I said, “Well, it’s funny because, yeah, there’s a lot of talk about estrogen, you
know, especially on social media. It’s like we finally have gotten to a place where
people understand and are willing to address the fact that women’s hormones cycle,
right, and that our hormones matter. And so, like, we’re there. But the only hormone
that anybody’s talking about is estrogen.
And so, so I wrote this book because it’s like, we know all of these like
wonderful, fantastical, functional things that estrogen does. Like, oh, estrogen
increases at times in the cycle when sex can lead to conception. And because of
that, we feel so sexy and alive and partners find us maximally attractive and all
of these things. And isn’t it great? And then it’s like, and then there’s
progesterone. And it’s like, oh yeah, yeah. And then there’s another hormone in that
other cycle phase. But it’s like, nobody really talks about it. And like, what is
that also serving a purpose? Like, what does that hormone do? Like, and so I really
got interested in trying to understand this, what I always like refer to as like
the dark half of the cycle, right? It’s the cycle, it’s the dark half of the
cycle, both because nobody knows about it, because nobody talks about it. And it’s
also the dark side of the cycle, because it’s a time that a lot of women don’t
like the way that they feel. And so I wanted to get in sort of unpack like what
is this hormone progesterone actually doing, right? And might some of these things
serve a purpose and then also why is it that we feel terrible? And so that’s what
the period of brain is like really all about. It’s trying to uncover this like dark
half of the cycle and try to better understand what it is that our body is up to.
And then also how we can minimize some of the psychological turbulence and physical
turbulence that women experience during this time. Well, I was really excited to see
your take on it. I mean, I really loved the approach that you took in your first
book. This is your brain on birth control. I mean, it was, I love the way that
you really delve into the science behind it because it kind of cuts through the
noise. It’s not just about what people are thinking about it or what they are
saying about it. And then it’s interesting because when you broach some of these
topics, there’s a lot of people who have, I don’t know, whether it’s just a lot of
negative opinions about it, or they kind of don’t like you questioning these things
or whatever it is. But when you just give them the actual science, I feel like
there’s not much else that can be said about it. Right. Yeah. Well,
it’s, yeah, it’s funny because there is a lot of people with very strong opinions
about the birth control pill and whether it’s good or whether it’s bad. And yeah,
and I do think that I came in and the message is like, it’s good and bad. And
it’s all about understanding the trade -offs and then figuring out where you land.
Because I mean, I really, whenever I’ve approached a research topic, whether it was
a birth control pill or in this case, it’s just women’s cycling hormones, it’s never
been with some sort of an end in mind about what I think other should be doing.
It’s, it’s always been something that I’ve approached as like a scientific curiosity
and trying to like uncover all of that. And I think that in the process of that,
and then just presenting the information to people, I think that people are able to
take that information and then use it in whatever way best serves their own needs.
And, and that’s, and that’s my goal, right? It’s like, I’m a university professor. I
spent my career teaching people. And, And that’s really what this is, is it’s like
an extension of my educational outreach. And yeah, and because of this, I think that
it does cut through the noise because it’s not, here’s how I think you should be
living your life and here’s what you need to be doing. And so it’s like, hey,
here’s some information for you and like, Godspeed. I love that. And I love that
you focused on progesterone. So I mean, that that hits for me because my kind My
first foray into that realm was through the work of Jerry Lynn Pryor with
Progesterone and Bone Formation, and it’s unreal when you actually read the research
about bone formation because it is all about estrogen, and nobody talks about
Progesterone at all, and even how they define HA as an estrogen -deficient condition,
which is true, but it’s like, “But there’s no Progesterone either.” Right. No. No,
it was so crazy. So I love her. I think that she is, she’s such a, like a
firecracker of a human being. I mean, she’s so smart and so energetic. And she’s
been, she’s been beating this drum for years and saying, Hey, hey guys, like we
have two primary sex hormones, not just one. And so I just learned, so I wrote
this book and it’s coming out at the end of, it’s coming out at the end of
September and just, and so I’ve been like deeply steeped in progesterone. And one
thing that I just learned was that in hormone therapy, that when people are being
given biologically identical hormone therapy, that they’re usually only given
progesterone if they still have a uterus. And the idea is that it doesn’t matter if
you don’t. And so women who are put on hormone therapy, if they’ve had a
hysterectomy, aren’t given progesterone because there’s this idea that with progesterone
that the uterus. And I stole this from Jolene Brighton. It’s like one of the
funniest things I’ve heard and it’s so smart is that they’re treating the uterus
like vagus, right? And they think that like, what happens there stays there, which,
which, which is not. It’s like, it’s a progesterone just like estrogen influences all
the cells in the body. And, and the idea that that we’ve somehow have this like
idea that it only matters if you need to thin out the cells in the endometrium is
just completely nuts. And it goes to show how much of a short shrift progesterone
has been given. And as you noted, like with bone formation, it plays a really
important role. Geraldine Pryor, Dr. Pryor has shown in her research that if you
just give women micronized progesterone that that can be just as palliative as
estrogen for treating hot flashes and menopause and paramenopause. And it’s so much
safer than estrogen because there’s a lot of women who can’t use estrogen either
because they have thrombotic risks. So women who have risks for strokes and blood
clots are oftentimes contraindicated against estrogen or women who have estrogen
receptor positive breast cancer. Oftentimes, they don’t want to have them on estrogen
and they’re not given anything. And so they’re just having to like suffer because
nobody’s really paying any attention to the fact that she’s got these really
beautiful, you know, randomized control trials showing that progesterone is just as
effective as estrogen in treating hot flashes, but it’s like nobody talks about
progesterone. It’s like just seen as this throwaway hormone. And the other thing
that’s crazy about it, and I’m sure you’ve seen this too, because Laura Briden’s
done a really nice job of amplifying this message as well. But it’s like, if you
actually look at, there’s this figure of the menstrual cycle that we all see where
you see this bump of estrogen, this big, beautiful bump of estrogen in the first
half of the cycle. And then you see this big bump of progesterone in the second
half of the cycle. And the way that it looks from the picture is that the bump in
progesterone is about the same size and magnitude as the bump in estrogen. But the
fact is that they’ve got that scaled at a level that’s 10 times the levels of
progesterone that are being plotted are at levels that are 10 times higher than the
levels of estradiol. And if you actually plotted it and had them both on the same
axis, the levels of progesterone are 10 times higher than peak levels of estrogen.
Peak levels of progesterone are 10 times higher than peak levels of estrogen in the
cycle. You never know that from these pictures that we see. And they said it looks
like estrogen is kind of run in the show. And we have this really huge levels of
this other hormone and nobody’s talking about it. We don’t know what it does. And
one of the takeaway messages from the book is like, “No wonder we all feel
terrible.” What’s even talking about it? Well, and that graph that you talked about,
I mean, that’s one of the most powerful teaching tools that I use in the, because
when people see that, all of a sudden it’s like, “Whoa, Progesterone has entered the
chat.” Right? Like no one realized, but no,
no, no, like there’s, if we were to kind of make a joke about it, it would be
like the Progesterone be hitting the ceiling on the grass, right? But we don’t
really think about it. And there’s no better example, like for the purpose of this
conversation, I feel like, than thinking about PMS. I mean, ask any woman who has a
really rough time in the post of how important progesterone is to her. I mean,
maybe because we’re not educated about her cycle, she might not understand that it’s
the progesterone, potentially, that is at the root of this issue, but ultimately it
makes such a big difference. So I mean, one of the things that you say in your
book is that PMS is not a biological defect, but a predictable response to a system
that ignores women’s hormonal reality. Of course paraphrasing potentially here, but
this is what we’re getting at. And I would love to hear you just delve into more
of that. And one other thing I’ll say is that one of the things that really struck
me is how you called out how research is done, right, on men. And this whole thing
of only focusing on estrogen, it’s like this is just my thinking, but it’s like
they’re trying to make this, well, men have testosterone, women have estrogen, and
they’re kind of just trying to make this comparison that doesn’t compute. – Right,
no, it’s a one -size -fits -all way of doing research that’s been based around a male
ideal. And so just to kind of get into this, When we look at the history of
science and research on human beings and even on non -human animals, it all started
out with researchers studying men and males, right? So male mice, male rats, human
males. And the reason that men were studied first is because nobody cared about
women, right? And so you move forward and finally people are like, “You know what?
We probably should care about women.” And so they decided that we needed to include
women and then female subjects when we’re talking about non -humans in research. But
then they had to deal with the fact that our hormones cycle, right? And that’s
another reason that it’s been really convenient to exclude women and females from
research is that we do have cycling hormones. And researchers know that these cycling
hormones influence everything in the body, right? So they know that if you’re
measuring a woman in the follicular estrogen as a primary hormone, then you’re
probably going to get a different set of responses from a drug treatment or some
sort of an intervention than you’re going to get if you measure her in the second
half of the cycle when progesterone is a dominant hormone. Researchers know this, and
because of this, they know that they need to find some way to account for women’s
hormonal changes, but rather than making the decision that women’s hormones matter and
for we can’t really actually understand women until we measure them under, in each
of their major cycle phases, right? When estrogen is the dominant hormone and then
when progesterone is the dominant hormone, they made the decision, like, well, let’s
just minimize the impact of their hormones on outcomes at all, and then we can just
measure them just like men. And so rather than studying women as women or females
as females, what researchers do in animal research, what they’ll often do is over
-rectimize the mice or rats. So they’re including females in research to say, “Look,
we studied females,” but they took out their reproductive organ so they’re not making
any sex hormone. And so essentially, they’re just like males. And then with human
subjects, obviously we can’t do that and get ethical approval. So instead what
researchers do is they only include women in research during the first nine days of
the menstrual cycle. So before any levels of hormones are very high. And when
estrogen is really the primary sex hormone and the only hormone that’s really being
released in any quantity at all. And so researchers did this, so that way they
could keep studying women the same way they’ve studied men, which is in this like
one size fits all sort of way. And a lot of this is really steeped in this idea
that what it means to be human is to be male. It’s like Our ideas about what it
means to be a human are all based on one day is the same day hormonally.
And any day I pluck you out of a calendar and measure you, it’s going to be the
same, you know, your body’s going to respond the same way it would any day that I
pluck your body out from a calendar.
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And with women, it just doesn’t work that way. But science never designed research
that includes women to actually understand women, right? Because if they were actually
trying to understand women, they would measure us at different times in the cycle so
that way we could find out how our bodies and our brains react to different types
of interventions, depending on which of the primary hormones is dominant, but instead
they’ve just minimized the impact of our hormones on outcomes at all. And what this
means is that all adding women into research isn’t actually being done in a way
that helps us understand women, and instead it’s just being done in a way that
allows us to pat ourselves on the back and say, “Look, we’re including women in
research. Look at all this, and it’s ludicrous, and it’s preventing us from
understanding women. And it’s also now muddying the water and making it so we can’t
really understand men, either. Because the other thing that happens in research that
a lot of people are unaware of is the fact that now that there are these mandates
that you have to include females in research, and so researchers are like, “Ha, ha,
ha, okay, that’s great. We’re going to include women during the first couple of days
of their cycle and hormone levels are low. But then what they also don’t do is
they’re not including sufficient numbers of males and females to be able to test for
sex differentiation. And so now you’ve got this like, this data that’s collected on
some women and men. And it’s never even looked at whether or not there’s going to
be sex differences in any outcomes, which is absolutely ludicrous, because we know
that there’s sex differentiation throughout the body. It’s like there’s not, as time
goes on, people in fields ranging from like cardiology. So heart doctors are starting
to understand that men’s and women’s hearts and their cardiovascular systems don’t
always respond the same way to the same types of treatments, right? To immunologists
who are beginning to learn that the way that male and female bodies deal with
things as simple as bacterial threats differ, right? We’re beginning to understand
that there’s sex differentiation throughout the body and that we’re not testing for
this. And then when we’re including females in research or women in research that
we’re only looking at them when they’re in the sort of under the beautiful spell of
estrogen, it’s no wonder that we feel terrible, right? Because not only have we
dismissed and sort of minimized the impact that our hormones have on all kinds of
outcomes, making women not really appreciate just how much of a remodeling project
their body is doing every cycle as they shift between these two different hormonal
states. But it’s also, it’s created these like guidelines for living, right,
from everything ranging from how much sleep we need to how many calories we need,
what sexual desire is supposed to look like, what our side effects for medications
are supposed to look like that are all one size fits all, right? And so they’re
all based on either men or on women in the early phases of the cycle. But the
fact is like, that’s not how we work, right? We’re cyclical. And so when we apply
these guidelines for, you know, what we should be eating and what sexual desire is
supposed to look like and what our side effects for our medications are supposed to
look like, that have been taken from the follicular phase when estrogen is dominant,
They don’t always apply to the luteal phase, and the fact is that it makes many of
us feel miserable. And one of the examples I give of this in the book is this
idea that we need to have X number of calories every day, you know, it’s like our
resting basal metabolic break requires that we have X number of calories a day. And
all of us have been force fed this since we were a kid, right? You need this
many, if you have this activity level, then this is the number of calories you need
a day. And that’s all well and good if you’re a man. But for women who cycle,
your basal metabolic rate increases between 7 and 11 % when you’re in the luteal
phase of the cycle. And that means that if you’re somebody eats 2000 calories a
day, you’ll need between an additional 150 to 200 calories a day, right?
This is not something that women are told about. And the results of that is when
they’re following these like one size fits all set of nutritional guidelines that
we’ve all been given is that women are feeling hungry, tired, angry, having food
cravings. And then they’re, they see their kids Halloween candy, right?
And then they go crazy because they’re hungry, and they’re not feeding themselves.
And then, and then they get mad at themselves, right? And then there’s this whole
narrative that so many women develop over the experience of being given guidelines
that don’t fit their bodies where women have this idea that their body is the
enemy, right? And that their body is the thing that’s standing in the way between
themselves and meeting their goal because they don’t understand why their body is
working against them. And they don’t realize that they’re working against their body
by doing what they’re told they’re supposed to be doing. And it’s because all of us
have been told, like, this is what it means to be human. You need this many
calories a day. You need this is what, like I said, this was sexual desire. It
looks like this is what your medication side effects look like. This is what the
symptoms of your chronic illness look like. And for women, it changes across the
cycle. And so most of us feel crazy about half the time because the way that we’re
responding and our body is responding to things isn’t the same every day. And we
really need to wrap our arms around that idea and with the fact that our hormones
matter, which is why I love, I love the work that you’re doing. I love the work
that other people in the space are doing. It’s like, it’s about time that we have
this awareness of how important these things are. – Mm -hmm. I mean, there’s so much
of what you said that I don’t even know if I can unpack, but I feel like, so
when I’m looking at research, I’m often looking at menstrual cycle research. And my
gripe is that they’re not tracking the cycle parameters in a way that makes sense
or that, right, like certain things like that. But you just took it to a whole
other level in terms of educating us about how research is done with the mice,
with the ovaries removed, or with what you said about how they just only test women
for whether it’s medication, side effects, things like that at the one time of the
cycle. I was being interviewed this recently And I was in a room with all these
men ’cause the men were the ones doing the AV equipment and the lighting and all
that. And I was talking about how they only recently started studying females and
female animals even and they were shocked and all these questions from the men were
just like, what are you talking about? But it’s like in name, it’s lip service only
based on what you’re saying. And I’m still there. When you said that, that really
hit and It’s just, it’s just so deep and vast how little we know.
I know that’s a weird way to say it, but like how little we know is so deep,
like it’s ridiculous. No, it is. No, it really is. And I mean, honestly, like one
of the things I’m right about in my book is that science needs a do -over. Like we
just need to, we need to scrap the way that we’ve been doing it because I mean it
was, it was all based on the idea of a male body and it doesn’t work for a
female body and instead they’ve just tried to shoehorn the female body into this
like one size fits all prototype and it just doesn’t work for us. And the result
is that we’re never studying women as women. We’re studying women if from a tiny
little moment in time that makes up about 20 % of our lives.
And that means that 80 % of the time our body isn’t responding to the way that
it’s being tested. And so it’s no surprise at all that we look at like medications
of something like 80 % of new drugs are pulled for market the first year of use
because of unanticipated side effects on women, 80%. And so, I mean,
that means that anytime a new drug comes out and you’re trying it as a woman, you
don’t know it, but you’re part of a trial because they’re just like throwing it out
there because it got approved because the studying women in this really any moment
in their cycle didn’t respond poorly to it, but the fact is our bodies metabolize
things differently across the cycle. Metabolism changes. Our immune system changes. Our
inflammatory processes change. I mean, there’s a million things that we don’t know.
Nobody’s even thought to test some of these things. Like, for example, we know that
during the luteal phase that progesterone, because it’s immunomodulatory, it ships us
from a anti -inflammatory, TH1 type of immune response, to a more anti -inflammatory,
TH2 type of response. I’m guessing that this means that there’s an optimal time in
our cycle to get an immunization, but nobody says to that, nobody’s like, it’s like,
it’s totally nuts. I mean, it’s just totally nuts when you, when you think about
the implications that recognizing that our hormones matter, like the implications of
this on the ways that we could vastly improve things like surgical outcomes, the
immunity developed from immunizations, et cetera, et cetera, et cetera, and the way
that we metabolize drugs and our side effects from drugs. And nobody has thought to
do this because everybody’s willing wants to just push forward with the status quo
because it’s easier and cheaper to do. But the easy and cheap isn’t the right way
to do it. And it’s going to be a way that that all but ensures that women are
never understood. – Well, easy and cheap for them, very expensive for us. – Yeah, I
know exactly. I wanna hear your thoughts on something because it occurred to me that
I’m always looking at menstrual research and there’s a lot of interest in this area
of kind of cyclical changes. So there are a lot of research studies out now about
like you said, the metabolism changes, whether women are sleeping differently at
different times of their cycle, whether they are processing their food differently or
whether their natural cravings go up and things like that. But I feel like even
that gives a false sense of security or a false sense of understanding, we think
that they’re making so much progress, but these are studies on that thing. They’re
not what actual drug companies are doing to determine if their products are safe for
us or appropriate for us at different times of the cycle. So I feel like you’re
hitting huge? Like, are you, are you the first person to be talking about this? I
don’t know that anybody else is talking about this really loudly. And it’s so funny
because in science, we have, we call it procedural inertia, right? And it’s, it’s
like where you get handed down from your research mentor, like a way to do
research, right? And then you just keep doing things the way that they, they’ve done
them because you’re told this is the right way to do it. And so you just do it
without really thinking about whether or not this makes any sense. And I think that
for me, because I kind of came into the world of neuroendocrinology from a
background in evolutionary biology. So my background was always very steeped in
understanding the evolutionary processes that have shaped sex differentiation.
So my whole background is on sex differences and like how the fact that because
women are the ones said are the ones who give birth and have to deal with
pregnancy and all of this, that this sort of puts us on a different evolutionary
path than the male path because we’re each having to solve different sorts of
adaptive challenges just based on our different reproductive biology. Right. So my
background has always been on like as an undergraduate and a young graduate student
was very much all about sex differentiation and like deep appreciation for the ways
that males and females differ. And then I go into the world of neuroscience and
neuroendocrinology and I see that the way that they’re studying females or women is
just by focusing on this little tiny narrow window in time and never actually
looking at what about them makes them different and instead just trying to make them
fit like men in a research design. I was like, this is, this doesn’t make any
sense at all. Like what, it is the gold standard. That scene is the gold standard,
because you’re keeping hormones consistent and like, isn’t that great? We’re
controlling for this extraneous variable, but this extraneous variable is like our
lives. It’s like if you’re a woman, you know, it’s like, that’s your life, that
extraneous variable. And it is bullshit. I mean, it’s just like, it’s just so, it’s
so nutty to me. And so I don’t know anybody else who’s speaking about this,
about this particular issue, but it is something I think like needs to be shouted
from the rooftops, because I think that it’s like, I think even some of the
scientists are doing this, if they actually sit with it for a minute and say, like,
do you think that this is going to actually help women understand themselves? Like
as they live? No. No, no, it’s not. No.
And then how deep does this go? Because how many women are on contraceptives? How
many women are past cycling? How It’s like, there’s other variables as well. So I
guess the like $100 million question is based on all of what you’ve seen and what
you wrote about. Do you have any, I’m sure you have ideas of how this could be
better. I don’t know that anyone has a silver bullet. – Yeah, no. So I mean, for
me, like in the last chapter of the book, I make some like, I say like,
like, here’s what we need to do. ‘Cause I really do think that science needs to do
over. And I think that there are two things that we really have to take the
spotlight. The first is understanding that sex differentiation exists throughout the
body and that we need to get rid of this idea of bikini because people talk about
bikini medicine, but bikini medicine is nothing more than a — it’s an outcome of
bikini science, right? Because science has all been done with this idea that the
only differences between men and women are the parts of the body that are covered
by a bikini, right? Hence bikini medicine and then bikini science. But that’s just
not true, right? And the more research that gets done, the more deeply we can’t
deny the fact that there’s sex differentiation throughout the body. And so we need
to, as researchers, go into studying men and women with the assumption that there
might So I don’t think that it should, that researchers should be allowed to have
study designs that don’t have sufficient numbers of each male and female participants
to be able to effectively test for sex differentiation in outcomes. Because sometimes
there won’t be sex differences in outcomes. So let’s say you’re looking at something
like, I don’t know, a pulmonary function and there’s something where there’s not sex
differentiation. Great, but that should be, the researchers should have to demonstrate
that there’s not sex differences. we can’t make the assumption that there’s no sex
differences. That shouldn’t be the null hypothesis. The null hypothesis should be
there are differences and that we have to show otherwise. If we’re going to get
away with only including males or only including females or lumping them together
without testing for sex differentiation. So that’s the first thing. Second thing that
needs to change is that women and females need to be studied as women and females.
And that means that we need to be studied at each of the major phases of the
cycle. And this is obviously, you can get, and I’m sure you do,
it’s like we can get a lot more fine -tuned than that, right? And again, get into
the cycle as like four phases, and then there’s this and this and this, but at a
minimum, looking at women when the primary sex hormone is estrogen, and women when
the primary sex hormone is progesterone, I think we’ll go a long way. And then
obviously moving forward, as we move forward in the world.
You know, it’s like, study, understand that there’s sex differences throughout the
body and you should test for them to study females as females, right? And study at
each of the major phases of the cycle. And then, so those are like my two, like,
let’s, if we do this, I think we’re doing pretty well. And then as we move
forward, I think, because women are, I mean, we’re a moving target. We also have
pregnancy, lactation, para menopause, menopause, we need to really start to understand
the limitations of our understanding of women while we’re not studying them in the
different phases, right, like of life. And so eventually, I think that we also need
to, with some of the things that we’re testing, if we’re interested in intervention,
and especially if it’s an intervention for menopausal women, then we need to be
studying menopausal women, obviously, or not so obvious, apparently. Yeah, no, not so
obvious, because it’s like, even with things like, they’ll test things on women, like
cycling women, and then tell pregnant women that these things are fine because they
don’t go through the, and usually the way that they, that they make that
determination is whether or not it goes through the placenta, but it doesn’t consider
the fact that the pregnant woman herself is a different version of herself, right?
Then she is when she’s not pregnant. And so determining whether or not something is
a good idea for a pregnant woman to be taking, the only litmus test shouldn’t be
just whether or not it passes through the placenta, right? It’s also that her body
is different. And is it safe for that? Is it safe for that body? And these are
questions that… Well, the hormone levels during pregnancy are just not the same at
all. Yeah, no. Wildly higher. Yeah, it’s much higher. And yeah, and again,
it’s changing your body at the same time. I know people refer to perimenopause as
like the second puberty. I refer to pregnancy as the second puberty because your
body literally changes. I mean, I got new breasts, like your brain is different,
right? And then it’s, you got a totally different situation going on. There’s even
research on how it can rejuvenate the cervical crypts. Like it’s just a whole
situation. Yeah. No, your body goes under like a major remodeling project with
pregnancy, and it changes you forever as noted. And in fact, there’s this really, I
have to tell you about this. I know you’re going to love it because it’s like,
it’s really cool research. But there’s this idea out there because you know that
women get like the rates of autoimmunity are just like through the roof relative to
men. And there’s this hypothesis out there that I think is so cool. And I think
that it’s spot on. And, and it’s essentially the pregnancy prevention hypothesis. And
it’s like, or the pregnancy hypothesis. And it’s, It’s this, and that is that
throughout most of history, humans spend a lot of time pregnant. Women did, because
we didn’t have, we didn’t have birth control, and presumably women weren’t charting
and cycling, you know, and doing all of the things. And so women spend a lot of
their time pregnant, a lot more time than they do now, and they’ve done some
average numbers of years that women spent pregnant by looking at contemporary hunter
-gatherer groups. I mean, several years of our lives spent pregnant. And there’s this
idea out there that because progesterone is like this very powerful anti -inflammatory
immunomodulatory hormone that one of the reasons that we may be seeing so many such
a high rate of autoimmunity in contemporary women is because we’re not pregnant so
much and that we no longer have this break pedal that was being pressed on our
immune system for all of these years that we spent pregnant. And the result is that
we have this unchecked inflammatory, pro -inflammatory type in immune response, which
could be contributing to the really high rates of autoimmunity that we see today,
which I think is a really interesting hypothesis. And I also think what’s really
interesting about that is that, especially for women who are on the pill who don’t,
they don’t get to experience progesterone. They just get those synthetic progestins,
which are not the same thing. And they don’t have these same beneficial effects in
the body, body is that if we gave these women micronized progesterone while they’re
on the birth control pill and see whether or not we can’t start to cut back on
some of these, lowering the rate of auto -immunity specifically in these groups,
because we do know that the birth control pill is also linked with a greater risk
of developing auto -immune disorders. So anyway, just another really sort of
interesting thing that it’s is the absolutely remodels our body, right? And has all
of these different types of effects, including putting the brakes on our immune
system. – Oh my goodness, I mean, that is so fascinating. And to add more to that
for women who aren’t cycling, who aren’t pregnant all the time, how many of them
are actually getting optimal progesterone? I feel like this brings us back to the
topic of PMS. I mean, I just, I spend my days observing charts And,
you know what I mean, kind of looking at it through a different lens and what you
can see when you’re looking at these symptoms through the lens of the chart is that
there’s often signs of low progesterone, whether it be short, luteal phase spotting,
whether it be lower temperatures or a sharp drop of a temperature too soon or
whatever it is that coincide with a lot of these PMS symptoms. So then from that
perspective, like to add more to it, even the women back in the day who were not
and all the time, they probably had more stable cycles. They probably, maybe the
environment was a little bit less stressful for them. And maybe they were able to
actually just live their lives through having a sufficient progesterone in the Lutile.
And maybe that also had some level of protective effect.
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Now let’s go ahead and jump back into today’s episode.
Yeah, no, for sure. I mean, when you look at the contemporary environment, it’s like
the number of things that are stacked against ovulation. I mean, it’s pretty
profound. And I was, and I write about this in my book, but I found in my own
research, because we do this cycle research, you know, we’re looking at the effects
of women’s cycling hormones and on their different types of psychological and
behavioral outcomes. And when I first started doing this research, And we would have
women in and it was only women with regular cycles, right? So who and and and felt
pretty confident that they were ovulating regularly and they were all healthy all
healthy weight Etc. Etc. Etc. Etc. And we would we would be studying this woman in
the lab and we would get failure to ovulate in about 30 % of our sample every
single time they were measuring it and these women’s cycles look Normal, right? Like
so they’re the same. They’re not skipping a day or they’re not too long and they’re
not too short and they’re just not ovulating and that’s I mean That’s crazy 30 %
and and when I talked to my my colleagues because at first I thought we were just
doing it wrong We were like messing up something and I talked to my colleagues who
study the same thing and they find the same rates It’s about 30 % and and I mean
and that’s like that’s insane and it’s it’s like he’s noted I mean, it’s like
stress, social isolation, right? All of these types of things, not getting enough
sleep, not taking care of your body, not eating enough. These kinds of things can
lead to these failures to ovulate, which then you don’t get all the really wonderful
benefits of progesterone across the cycle, and that also is associated with worse
mood outcomes. – Well, this is, I’m so fine. Like I feel like there’s a hundred
directions we could go in. I mean, What are the implications then for your average
woman who just feels like her period sucks? There’s still, I think we’ve come a
long way. It’s been just amazing to see how the conversation has shifted around the
menstrual cycle over the past 20 years. I keep asking you how old am I? But it’s
really interesting because when I first learned about charting and about cycle
tracking, no one was talking about it. There was no such thing as a podcast, right?
There wasn’t a lot of this stuff going – Right, there was no social media either.
But things are so different now. Like people are talking about it, women are kind
of putting it out there. But my question would be, are people feeling better?
– Well, no, I think that when women start to learn the stuff,
I do think that it helps everybody feel better. I think there’s a lot of people
who are still feeling pretty bad. And I think that the answer to those women is
one is just like understand what your body is doing. And so one of the reasons
that I wrote the period brain is I really wanted to understand like what, like,
what is the body up to in the luteal phase? Like, like, why is it that we
experience some of these experiences that we all have that make us feel less than
ideal? And so understanding what your brain and your body are actually trying to do
as your body is shifting from a state that’s optimized for sex and conception and
then switching into a state that’s optimized for implantation and pregnancy. The body
does undergo a little mini remodeling project every single month as it goes between
those two states and understanding what your body is doing and why it has the
experiential effects that it can. So like, for example, like explain some of the
things that go on in the brain that can lead to kind of low key feelings of lack
of motivation, right, because we do get our brain changes the outside world to seem
less rewarding to us so that we were not chasing rewards all the time, because we
do need to conserve energy. It’s a very metabolically expensive time in the cycle,
our body is remodeling tissue, which ends up being an incredibly expensive thing to
do. And so our body is oriented toward energy conservation at this time, making us
sleepier, making as less sort of outwardly facing, turning our energy inward and
understanding some of these things or the changes in sexual desire that many women
experience in the luteal phase, which is when sex becomes less about like this sexy
act that you have to have and instead become something that is a tool of
connection. And so it’s like serving a different set of motivations, which means that
it’s also going to
So educating yourself about what all of that is, and I think I do a pretty good
job of I lay all that out in the period brain in the new book. And then also
understanding that there’s a lot about our current environment that is eroding our
sort of resilience to hormonal changes, right? So as you and I talked about at the
beginning of the hour, the luteal phase is this time of just intense hormonal
change, because I mean, you have these huge rises and falls of progesterone that are
again like 10 times higher than the levels of rising and falling of estrogen in the
first half of the cycle. And you’re also getting a rise and fall of estrogen in
the second half of the cycle as well. And so it’s this time of huge hormonal
change. And for most of history, we lived in a way where we had a lot of
resilience to any type of internal or external stressor. And that’s been eroded by
our modern environments, right? There’s a lot of things that erode at our resilience
or the resilience of our cells to be able to quickly adapt to internal changes.
And given that you have all of these huge hormonal changes and with these hormonal
changes come changes in neurotransmission. So just for example, we know that
progesterone when it gets broken down in the body, turns into this really lovely
metabolite called allopregnanolone. And it has this really nice relaxing effect on the
brain, and it can be very kind of almost almost soothing. It’s like this like
really nice hormone. But when it’s going up and down and you’re not, your cells
aren’t able to adapt to those big changes of up and down, it can feel really
terrible. Because imagine that you’re a neurotransmitter and you’re getting bathed by
this like inhibitory relaxing effect, and all of a sudden it’s gone, and you’re like
trying to find it and everything feels crazy, that’s a lot of what’s happening
because of the ways that our environment has minimized our cells’ plasticity and
ability to quickly adapt to different types of hormonal and different types of
neurotransmission changes. And so another thing that I recommend is just taking steps
to try to increase your resilience to hormonal changes, to try to make these changes
that we experience, even though they’re still noticeable, less like you’re careening
off a cliff and feel more like you’re just sort of riding, you know, riding a soft
wave. And so, and these are just like the basic pillars of health, right? So it’s
like not eating processed foods and moving your body and getting morning sunlight.
So you can set or cation rhythms and that way you’re able to get enough sleep,
right, listening to your body when it’s telling you we need sleep and rest to be
able to take that time to restore having a community around you, which is one of
these things where I think that like on one level I think everybody knows that
stress is bad for them. Like if you ask people like, hey, is stress good for you?
And they’ll say, no, it’s not. And so we all know that, but I don’t know that
most people know just how bad it is. I mean, just in terms of like the way that
it erodes at our, at our hormonal health and the way that it erodes at our ability
and resilience to things like hormonal changes. Because when we don’t have a village,
like if we don’t feel social support and we don’t feel safe, like A, that’s going
to interfere with ovulation because our bodies don’t like to ovulate if they don’t
feel like the world is a safe place to be able to have a pregnancy and so it
erodes at that but then it also it increases inflammatory activity because anytime
that we see the world is dangerous or or too much for us to handle which is how
we feel when we’re stressed our body releases inflammatory activity as a way to be
able to be ready and on guard in case you become injured because historically the
times that we felt stressed were times when physical danger was a potential threat,
right? And even though that’s no longer true, we still have the legacy of our
ancestors. And so when we get stressed out, it increases inflammation and
inflammation, erodes that are cellular plasticity. And so anything that we can do to
just sort of build on the basic pillars of health, I think are incredibly important.
And they really can do a huge service in terms of increasing our resilience to
hormonal changes and allowing ourselves to ride that wave and have it feel minimally
unpleasant.
I just, I love this conversation so much. And being a podcaster for many years,
I feel like I’ve had the privilege of interviewing so many different incredible minds
talking about similar topics in a very different way. And I feel like this is one
of the first times I’m hearing about kind of like the brain science, right? Behind
what’s happening in our cycles. And yeah, it’s really fascinating conversation for me.
I’m sure our audience is loving it as well. And I mean, I think it’s amazing.
And in some ways, it almost makes me sad that we have to do this much to be
heard, right? Like women have been saying these things in different ways for so
long, but we really do need the researchers to pull the science on it and to call
it out so that we can actually get something done about it. – Yeah, no, I think
it’s sad. It’s sad that it takes somebody having to come and pull out a chart and
a list of references for people to listen because it’s like, yeah, this is the
stuff that women have been talking about for years and it’s nobody was really paying
any attention or thinking that they were crazy. And it’s only recently that even
like the medical community. It’s like for a long time, doctors would, whatever, you
know, it must be in your head. And I think now doctors are finally starting to
understand that the science that they’re being trained on is very limited. And so I
have seen like one positive change, I guess I’ve seen is that I do think that
doctors are more like, look, women have been studied very well. So like I’m
listening to what you’re saying. I don’t know what to do about it, but at least I
believe you and I feel like that’s at least the stuff in the right direction. I
mean, it’s, and obviously we need to go a lot further because just sympathy only
goes so far. It’s like at some point you want to fix the problem, but I really
think that trying to get a handle on the fact that our cycles matter and as our
hormones change, it changes the way that we experience our bodies and that affects
everything ranging from, like I said, it’s like things like our emotional states, our
ability to manage stress, right, the way that our sexual desire manifests, the way
that we respond to drugs for chronic conditions, the symptoms we have of chronic
conditions. I mean, all of these things can change across the cycle, and women
aren’t told about any of them. And so instead, they just kind of feel like they’re
crazy. And so my one hope That well one of my hopes right so one of them is that
we totally we give science the do -over that it needs In order to best serve the
needs of women but also I want women to have the tools that they need themselves
to be able to just start to really get a handle on Their body’s relationship to
their hormonal changes and then how that impacts the things in their lives that are
really important to them So in the book for example, I talk about the ways that
progesterone influences everything, right? And so, and really starting to track.
So for example, if you’re a woman who has a chronic condition, because one of the
things I talk about in the book is how our symptoms of chronic conditions change
across the cycle. And for some women, they find that their medication doesn’t even
work as well during certain points in the cycle. And so if you’re a woman with a
chronic condition, whether it’s a mental health condition like ADHD, or whether it’s
a chronic health condition like asthma. A lot of times women will notice
breakthroughs in their symptoms where they’re not being managed very well by their
drugs. And there is some research on certain types of conditions where doctors have
now recognized that this is in fact something that happens and that women might need
additional, they might need additional care during the last two weeks in their cycle
because that’s generally when most women have worsening of different types of symptoms
that they experience. And so for example, with things like asthma, it might mean
that you have more than one type of treatment that you use during the second to
have the second two weeks of your cycle, because this is a time when many women, I
think it’s me, like 80 % of asthmatics experience premenstrual worsening. And they
define premenstruals anywhere between two weeks to a week before your period starts.
A lot of women experience luteal phase worsening of asthma related symptoms. And so
getting that extra care. So during that time, you don’t feel like you can’t breathe
can be really helpful. Oh, my goodness. I mean, I could talk to you all day,
and then probably all week, we’re gonna have a little retreat, have a mini retreat
where we just sit and ask each other questions. But this is, I mean, on the one
hand, like, it’s amazing, what a time to be alive, right? Like, this is being
talked about in big platforms now, we’re actually getting all this information out
here. And on the other hand, it’s like women have been saying these things for a
while. – I know. – So, but it is truly amazing. I am so thankful for you and for
the work that you’ve done in this area. I just love the topics that you touched on
today. And obviously they need to be shouted loud and wide and long from all of
the places so that we can inspire the change that needs to happen clearly in
science. I mean, I’m sure that I’m generally outraged. So I don’t know if my
outrage counts, but I’m sure that we have plenty of listeners that are outraged to
think that they’re taking medications that were only tested on a part of their
cycle. And we just have literally no information about how it affects you for the
other half of your life. You know what I mean? Like it’s completely insane. – It is
insane. – So as we draw this interview to a close, I would just love to hear your
final thoughts. I mean, for someone who tuned in and thought they were just going
to have a run -of -the -mill conversation, but got their mind blown over and over and
over again. Where does she start? Or just, I guess, I don’t know, I’m sure you
have plenty of words of wisdom for us. Yeah. So, I mean, the first thing is just
really understanding your cycle. And I’m assuming that most listeners who know about
cycle charting, all the wonderful things that you do know that like, like keeping
track of what’s happening with yourself hormonally is like the first is really the
first step in everything. And, and starting to get not only a feel for what’s
happening as you’re doing your charting, but using that and then also evaluating how
you’re feeling, checking in with yourself, right? And starting to learn your own
different patterns within the cycle. So when it comes to everything that’s important
to you, so things like your mood, sexual desire, performance at work, appetite, your
workouts, are you having side effects from the medications that you’re taking? These
are things that I think that starting to track regularly across the cycle can be
incredibly important just in terms of understanding the way that your body responds
to hormones because even though there are some patterns that we tend to see that
are pretty reliable between women, each woman’s relationship with her hormones is a
little bit different and it’s like good to get a handle on what yours is. And just
to give a quick example, even though most women feel great near ovulation, there’s
about 10 % of the population and that feels the worst right near ovulation. And
which is like one of these things we don’t have an answer for it. But if you know
that about yourself, then you know when to put in the safeguards. And so starting
to understand your relationship with your own hormones, I think is really important.
Number two, obviously I’m gonna have a plug for my book, The Period Brain. I really
do try to unpack for women everything that’s happening in the body in the second
two weeks of the cycle. So that way they can actually have a roadmap of what the
luteal phase is supposed to be about. And that way they can understand what’s
happening in their body. ‘Cause I’ve found that when I have language to describe
what’s happening to myself, it’s really easy to talk myself out of feeling things
that I don’t wanna be feeling. And also being able to communicate with people around
me to be able to make sure that I’m able to recover from whatever it is that I’m
going through, whether it’s just having a moment or if I’m having difficulty with
sleep or exercise or whatever. It’s something I can talk about and I’ve got language
for it and it makes sense. And so checking out the book, I think is also helpful.
And then lastly, it’s really believe your body. It’s like,
learn, I think one of the things that his disheartening about all the conversations
that I’ve had with women over the years and through my research and just through
conversations with readers and others and friends is how many women have an
adversarial relationship with their body. And I think that a lot of that is because
we all have been fed this one -size -fits -all idea about what it means to be human.
And so even when we’ve been following all the rules that we’ve been told that we’re
supposed to follow to have good health and good nutrition and good rest and good
friendships and so on and so forth, that most of these rules have been created for
male bodies and they don’t always work for our bodies. And the result is that we’ve
had a lot of times where we felt like we were doing what we’re supposed to and
our body was rebelling and then we learned to distrust our body. And so like
another thing that I think is really important is to try to start to reestablish a
new and trustful relationship with your body where you start to believe what it’s
telling you and then use that as a guidance for the path forward, right?
And so starting to develop a trusting, loving relationship with your body, listening
to what it’s telling you and then sort of going from there. That is incredible
advice and I highly recommend for anyone who found this conversation interesting like
run to like pull out your phone now and grab the book. And one of the reasons I’m
saying that as well is because, sir, your approach to writing and research is just
very different. So even if you’ve read a whole bunch of books on the menstrual
cycle and those types of things, you’re not getting that same book. This is a very
different approach. And I feel like you never disappoint with your just the rigor of
your approach and your creative mind. I love that you just, you’re thinking about
these things and you’re wanting to figure out why and you’re doing it, right? And
that’s what makes your books very unique, very interesting, very informative. And I
really mean that because I’ve seen a lot of like a lot of books across my desk,
right? I’m guessing that’s true. Yeah. So this definitely isn’t just your regular
book. You can tell by your conversation. Like these are topics that really haven’t
even been broached. So I mean, just congratulations. I’m so thrilled to be able to
support you in getting the word out. Thank Thank you so much. It’s always such a
pleasure. I’ve so much fun talking with you, Lisa, every time. You too. Likewise.
I hope that you enjoyed today’s interview with Dr. Sarah Hill. I obviously was
fascinated and really enjoyed the conversation. I feel like you can tell just by my
responses. And it’s not every day that I’m faced with brand new information,
brand new research, and even a brand new way to to understand some of the holes
that seem to exist in our healthcare system as it pertains to women. I feel like
Dr. Hill has really uncovered this huge, I mean I would call it a dirt little
secret, but just this huge issue with the way research is done. I mean that
certainly stood out to me quite a bit in the interview and it’s one of my biggest
takeaways from this interview that even when they do include women in research and
female animals in animal research, whether it’s especially as it pertains to certain
drugs and medications, we’re only getting the tiniest window into how these
medications might be affecting us because they’re leaving out the parts of the cycle
where our hormone levels are the highest. So they’re not testing for these
medications before ovulation when our estrogen levels are really high. They’re not
testing in the post -op when our progesterone is significant. And then that would
bring me to other questions, like, well, what happens with women who are on birth
control and how might the responses of a woman on hormonal contraceptives,
contraceptives that suppress the natural production of her natural hormones, estrogen
and progesterone, how might that change how she might be affected by these different
medications. And as Dr. Hill touched on, how is it then different at different times
of the life cycle? How is it different during pregnancy? How is it different during
lactation? How is it different in premenopause? How are hormones affecting the
efficacy of the medications that we’re taking? And what are the implications of that?
And so it’s a really profound way to look at it and to really kind of look at
this issue. And And when you add in also the way that we live our lives and the
different societal pressures, the stress, and this kind of invisible expectation that
we move through society like men. When we add that all together, it does make sense
why so many women are struggling and why one of the biggest challenges that we have
is trying to understand what’s happening with our hormones. So this was definitely an
enlightening conversation for me, and I hope that you enjoyed it as much as I did.
I feel that this episode is definitely one worth sharing, so if you could think of
someone that would benefit from hearing today’s episode, you can share the episode at
fertilityfriday .com /593. You’ll also find the links there to Dr.
Hill’s books and any of the other relevant information that we talked about today.
So with that said, I hope have a wonderful week weekend whenever you’re tuning into
the show. And of course, as always, until next time, be well and happy charting. If
you’re loving the podcast and you’re ready to apply fertility awareness strategies in
your women’s health practice, then I know you’ll love our Fertility Awareness Mastery
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