Are low-dose birth control pills more natural?


Photo by Anna Shvets on Pexels.com

Low-dose birth control pills entered the market to make the pill safer for women. Which, thank goodness they did. The original birth control pills had pretty high levels of progestin and ethinyl estradiol, the latter of which increases women’s risk of experiencing things like blood clots and stroke, which are outcomes that most of us want to avoid. So, lower dose pills have been nothing short of life-saving for hundreds, if not thousands of women.

But are they more natural?

First, some necessary background information. Like what a low-dose birth control pill actually is. A pill is considered low dose if it contains less than 30 micrograms (mcg) of estrogen, and those that contain 10 mcg of estrogen are considered ultra-low-dose. This is the smallest dose of estrogen available in combination birth control pills. It’s worth noting that most pills that are currently on the market are considered low- or ultra-low-dose. This includes both combination pills (estrogen and progestin) and progestin only products (which have 0 mcg of estrogen).

Given that low-dose pills (especially those that are ultra-low-dose) contain less synthetic estrogen than their higher-dose counterparts, there is a tendency to assume that they will put our body in less of an unnatural state than those containing more synthetic hormones. There is also a tendency to believe that the low-dose label means that they will be associated with fewer psychological side-effects, like changes in mood or libido. But these ideas – even though they make sense when you hear them – probably aren’t true.

Let’s start with the natural thing. Which I get. It makes good, intuitive sense that fewer synthetic hormones = less fake stuff in the body = more natural.

But it isn’t necessarily going to work this way.

To get to the heart of this, let’s talk a little about a natural cycle. Each month, women’s hormones go through a beautiful ebb and flow that is the natural result of an egg maturing and being released from an egg follicle. This includes the estrogen-dominant follicular phase, resulting from egg follicles being stimulated and eventually developing a mature ovum. It also includes the progesterone-dominant luteal phase, which is created by the temporary endocrine structure that gets created by the empty egg follicle whose job it is to release progesterone. See my picture below to see this illustrated (taken from my book). And take it in! It’s such an amazingly intricate act of neuroendocrinology. And it happens every month. It still leaves me awestruck….


As you can see, women’s natural cycles are punctuated by a lot of hormonal activity. Like, a lot. And these hormonal changes help to create the “natural” experience of being a woman. Peaks and valleys. Highs and lows. A dynamic experience that (in my experience) makes life feel vibrantly three-dimensional.

Now, look and see what this all looks like on the birth control pill (also taken from my book).


Above, you are seeing the levels of synthetic estrogen and progestin that are in a randomly selected version of the birth control pill (which I can do because they all work pretty much the same way). This daily dose of progestin (plus estrogen, here) creates a hormonal milieu that prevents egg maturation / ovulation and thereby suppresses women’s own production of sex hormones. So, with the pill, you experience hormonal deja vu from synthetic hormones, which prevents the release of women’s own sex hormones. So, women’s hormonal experiences are pretty much a hormonal deja vu with the message being the one that is provided by the hormones in the pill.

So, what happens with a low-dose pill?

Well, with a low dose pill, you are probably not creating a situation that is more “natural”. Instead, you are simply turning down the volume on the synthetics, leading to less (synthetic) hormonal activity in the body. Remember, women’s own hormones are suppressed**, which means the majority of sex hormonal activity going on in pill-taking women’s bodies and brains is from their birth control. This could actually feel less natural to women than the experiences created by a higher-dose pill because a typical hormonal state for naturally cycling women is one punctuated by a lot of hormonal activity.

And there is evidence that this could be the case, at least when it comes to mental health. Research on the relationship between hormonal birth control and the risk of developing depression seems to indicate the the risk is greatest for some of the products that contain the lowest levels of synthetics, in particular, non-oral products like the vaginal ring and hormonal IUD. This is far from a smoking gun (extremely far!!!), but it is worth making a mental note of the fact that low levels of hormones don’t necessarily mean that you are going to be feeling maximally like yourself. Or that you’re going to feel more “normal” or “natural” than you would with a higher dose of synthetics.

**Let me add the tentative caveat that some of our most recent research indicates that women on ultra low dose pills **may** produce relatively higher levels of their own estrogen than women on higher dose pills (although, still far less than what is created in a natural cycle). This could maybe be interpreted as being more natural and may feel more “normal” to women. We are waiting on the data telling us how these women feel… [stay tuned]. We also know that lower dose prescriptions prompt the release of fewer sex hormone binding globulins, which would make less of women’s testosterone unusable by the body. This could also be interpreted as being more natural? Although this feels a bit like splitting hairs, this could be a biologically meaningful difference in some women, making them feel more at home in their own bodies.

The big take-away, here, is that each of us should choose the dose that feels most natural to our own bodies. Because no matter what you pick – if you are on hormonal birth control – it’s going to be unnatural (see figures above). That isn’t necessarily bad. It just is. There are plenty of natural things that are terrible (SARS-CoV2, anyone?) and plenty of unnatural things that are life-saving (ventilators). So it shouldn’t be about natural. It should be about how you feel. YOU. For some women, this might mean a higher dose prescription. For others, it might mean a low- or ultra-low- dose equivalent. Tune in to your body, trust how you feel, and work with your doctor to troubleshoot your prescription. Above all else, be patient and kind to yourself. That should be the most natural thing that any of us ever do. ❤

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Low Progesterone, Stress, and Inflammation

Photo by Andrea Piacquadio on Pexels.com

If your mood is all over the place and you’re having a hard time managing your stress right now, you’re not alone. A lot of us are struggling. For some of you, though, your quarantine / the-world-is-a-dumpster-fire anxiety may be being made a whole lot worse by low progesterone [P], or low P. Although low P is typically called a luteal phase deficiency [LPD], I think some rebranding is in order. My hope is that calling this struggle low P – just like calling hypogonadism, low T – will start more conversation about this topic and get it the attention it deserves.

Typically doctors become aware of low P because women are spotting between periods or they are having difficulty getting or staying pregnant. It is also sometimes co-diagnosed with things like PCOS, endometriosis, and perimenopause. However, a growing body of research in psychology and neuroscience suggests that low P may show up in women as difficulty regulating stress, inflammation, and mood. And this is a big deal because there are a huge number of downstream consequences that come along with these sorts of issues, including problems with mental health, weight gain, and cognitive decline.

So, let’s get right to it.

First, stress.

You all probably know that cortisol is a stress hormone. But what you probably don’t know is that one of the tools that the body uses to regulate cortisol release in the body is P. It does this primarily through the action of allopregnanolone [ALLO], which is a neurosteroid that gets released when P is broken down by the body (read more here). And this is a big deal because because a lot of mood-related disorders – including major depression, postpartum depression, PTSD and alcohol use disorders – are characterized by (among other features) cortisol dysregulation (see this for a review). These dysfunctions generally involve cortisol being too high when the body is in a resting state and being too low when the body is stressed.

Interestingly, this is exactly the pattern we see in one group of women who are known for having chronically low P and staggeringly low levels of ALLO: women on the birth control pill. As I talk about at length in my book, women on the pill have cortisol responses that are notorious for misbehavior. Their levels of cortisol that are too high when they are at rest, they are too low when they are experiencing stress (see e.g., this), and their daily curve is too flat. And every other part of the signaling pathway is equally jacked… but no one in the research literature has been able to offer a good explanation for why…

But it has to do something with P. It would be impossible not to.

Although this might sound like bad news, this could be great news for therapeutic treatments. ALLO may be able to be used to treat HPA-axis dysfunction (and the resulting mental health side-effects) that are so often observed in women on the birth control pill. And this could be HUGE. So many women go on the pill because they feel like they don’t have better options. Anything that we can do to ease the mental health burden put on these women is a huge step in improving the quality of reproductive healthcare until we have more contraceptive options.

Understanding the role that P and ALLO play in regulating cortisol could also provide insight into some of the unpleasant symptoms that occur during perimenopause and menopause. During the ever-magical perimenopausal transition, levels of P and ALLO decline and levels of cortisol go up. And I don’t think that this is a coincidence. Supporting P and ALLO during this hormonal transition could possibly ease some of the cortisol-driven symptoms that women have during this time, such as mood changes, hair loss, and the accumulation of belly fat (more on this in a minute).

Having low P can also lead to elevated inflammatory activity in the body since P and ALLO help keep inflammation in check. And this is no bueno since inflammation is linked to things like heart disease and certain cancers, as well as mental health issues like anxiety, depression, and problems with cognitive function. So anti-inflammatory are the activities of P, P and ALLO have been found to be therapeutic in treating traumatic brain injury, cocaine addiction, and postpartum depression. And research in animal models has also found it to show promise as a treatment for multiple sclerosis and Alzheimer’s disease.

So, what’s a girl to do when she wants to boost levels of P and its metabolic side-kick ALLO?

Thankfully, there are a number of ways that you can naturally support your body’s synthesis of P and ALLO. The two that seem to be the most important are (a) eating a nutrient-dense diet, rich in vitamins C and B6, magnesium, zinc, and Omega-3 fatty acids and (b) managing stress. If you are doing all of these things and still have low P, you can consider supporting progesterone production by supplementing with Vitex agnus-castus, using a micronized progesterone cream, or by supporting your thyroid. I would talk to your doctor or naturopath before trying any of these latter ideas, though, since you should have your P levels monitored.

If you aren’t in a position to be supporting P – either because you aren’t ready to ditch your birth control pills or you are menopausal and aren’t interested in hormonal replacement – all is not lost. You can help promote cortisol regulation and manage inflammation in other ways.

For example, a growing body of research suggests that many foods can modulate inflammation and improve stress-related mood disorders. Diet is the most potent modifiable risk factor in the fight against systemic low-grade inflammation. And this is super-important because chronic inflammation is involved in several chronic diseases, including mood disorders, but also cardiovascular disease, obesity, diabetes, autoimmune diseases, and neurodegenerative diseases like Alzheimer’s.

So, what should you eat? It’s the usual suspects. Omega-3 fatty acids have well-known anti-inflammatory and anti-allergic effects because they keep the immune system in check. Foods rich in omega-3s are walnuts, sunflower seeds, flax seeds and fatty fish, such as salmon, salmon, and salmon (I really like salmon, so I stopped reading the research paper once I saw that: YUM!). So heroic are these fats in the fight against depression that a recent meta-analysis suggests that they may be an effective treatment in perinatal and postpartum depression. Which is huge! Let food be thy medicine, indeed.

Another bioactive compound that packs a big punch when it comes to brain function is vitamin D. Vitamin D is involved in brain development and neuronal activity and deficiencies are a risk factor for neuropsychiatric disorders, including postpartum depression, major depressive disorder, and schizophrenia. Major dietary sources of vitamin D are egg yolks, mushrooms, shrimp, herring, sardines, and (my favorite!) salmon.

Lastly, find yourself a good source of resveratrol. This naturally occurring antioxidant shows beneficial effects on depression and anxiety by suppressing inflammation in the periphery, as well as in the brain. Resveratrol, which is present at high levels in red grapes, nuts, dark chocolate, and pomegranates. It is also in red wine, which is my favorite. It has positive metabolic, antioxidant, and anti-inflammatory effects on the body and is neuroprotective.

As much as I would love to tell you that I am going to leave P alone – and start to talk about something else – I have one more Progesterone-a-rific post left to share. I have been reading some super interesting things about progesterone and pain perception that every woman needs to know. The reason you need to know is because it will arm you with the information you need to dismiss your doctor’s claim that your unexplained physical symptoms are all in your head. I will break down everything you need to know to school your doctor on pain perception and hormones. Until then, take care and be well.

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The pill and… sexual orientation?

So, I have been contacted by a handful of readers now who have told me that going on or off the pill seems to have impacted their sexual preferences. And it’s not just in a “my pill seems to have impacted the qualities I desire in my male partners” kind of way. It’s in a “I identified as a lesbian for a decade while I was on the pill, but now that I am off it, I am no longer attracted to women, but attracted to men.” And I have also heard the opposite. In these cases, the emails read something along the lines of “I identified as a lesbian until I went on the pill, but after going on it, I developed attraction to men”.

My mind is blown. Yet, it probably shouldn’t be. [Yet, it still f***ing is!].

I say that my mind shouldn’t be blown because…well, it shouldn’t be. Decades of research has found that women’s sex hormones impact their attraction to specific members of one sex. Why shouldn’t it also impact their attraction between the sexes? Which seems really wild, but maybe it isn’t. And if we are to take seriously the idea that gender isn’t as binary as biological sex, it really isn’t wild at all. It just goes to demonstrate that sex hormones are intimately involved in attraction and – for some women – the hormonal changes initiated by the birth control pill can nudge their preferences in ways that are more noticeable than they are for others.

The other thing that this got me thinking about was the phenomenon of mid-life sexual orientation changes. This is the thing where women who were previously only involved in relationships with men (or women), once they are in their 40s or thereabouts, start getting involved in relationships with women (or men). In other words, the gender of their preferred partners changes. I think that there is a tendency to assume that this sort of thing happens mostly in response to cultural pressures. For example, if we know a woman who was previously only involved with men who started dating women later in life, there is a tendency to assume that she was probably interested in dating women all along, but didn’t feel safe coming out as a lesbian until she was older. And there is good reason to believe that, for a lot of women, this is exactly what goes on. People who fall outside the cisgendered, heterosexual mold are still routinely discriminated against and, for many, coming out can be scary and even dangerous. But given that the hormonal changes initiated by the pill may have the ability to nudge some women’s sexual preferences this way and that, it also seems possible that mid-life changes in women’s partner choices might also occur because of mid-life changes in sexual preferences. That is, it seems pretty plausible that the mid-life hormonal changes that women experience as fertility begins to decline could nudge women’s partner preferences in ways that – for some women – produce changes in the sex of their preferred partners.

All of this is utterly fascinating to me. It raises so many interesting questions about women’s sexual psychology, attraction, and even the whole notion of the self. A person’s self – which is our perceptions about who we are – is believed to be relatively stable. But given that hormonal changes may change our self in important ways, this view of the self could actually be a totally gendered assumption that applies less to women than it does to men. That is, the idea that each of us is a relatively fixed person (and that to be otherwise is pathological or deviant in some way) may be an assumption that was created based only on the experiences of men, whose hormones change less across the lifespan. For women, it may be the norm for the self to constantly evolve. We may have selves.

I would love to hear your own thoughts on any of this. Do you know anyone who has experienced changes in sexual preferences on the pill? Has your notion of self changed in response to hormonal changes? Are our views about the self male-centric?

Xoxo. Stay healthy and be well.


This is my brain on writing.

I am a research psychologist and professor who studies relationships and health. I am also a writer, speaker, and consultant with a passion for helping people understand how to use science to help them feel happier, healthier, and better connected with others. My book, This Is Your Brain On Birth Control: The Surprising Science Of Women, Hormones, And The Law Of Unintended Consequences is out now.

This blog is going to be where I post original articles about all-things related to wellness and relationships. There will also be a lot of articles that are of special interest to women since: (a) I am one, (b) I have spent much of my research career studying them, specifically, and (c) I have a lot of things to say about the birth control pill that couldn’t fit into my book.

I will also be interspersing this sort of content with other things that I am thinking about at the moment (like food, natural approaches to wellness, and other psychology- and health-related things). Food, sex, and the brain…who could ask for something more in a reading space? And when you combine all that with my gratuitous use of the word f**k, I think that you’ll agree that there are few other places quite like this one on the internet**.

**I’ll let you decide whether that’s for better or for worse.

I love hearing from all of you, so please feel free to leave me comments, send me email, or message me on social. My handle is @sarahehillphd on all platforms.

I’m looking forward to getting started and having the opportunity to connect with you all.

Xoxo. Sarah


What is the truth about midlife birth control pill taking?

Does the pill make sense when you are 35+?

It wasn’t all that long ago that doctors used to discourage all women – regardless of their health or lifestyle – to go off of the birth control pill once they were 35 or older. However, times have changed. Not only have birth control pills, themselves, become safer (they contain much lower doses of hormones than they used to, minimizing the risk of cardiovascular events); the science now tells us that, for healthy, nonsmoking women who are older than 35, the mortality risk associated with pill use differs little from the risk to much younger women. Although doctors continue to recommend that women 35 and older use a pill with the lowest hormone dosage possible, it is now understood that most commercially available birth control pills can be safely used by healthy, nonsmoking women until menopause (which is typically assumed at age 55).

Given the relaxing of restrictions that used to prevent women in their midlife from using hormonal forms of contraception, a growing number of women in their mid-30s, 40s, and 50s are finding themselves on the birth control pill. For some women, this reflects their first foray into the word of hormonal contraceptives. However, for many others, this is simply a matter of habit. They were on the pill throughout their teens, twenties, and thirties (with some taking breaks to have children). Now, they’re continuing to use it because their doctor never told them that it was time to stop or consider alternatives. This has led many women to begin wondering to themselves about whether using the pill for so long is safe and what it might be like for them once they eventually go off of it.  

First, let’s talk about the benefits of midlife pill use. And there are quite a few of them. The big one is, of course, pregnancy prevention. Although the idea of a pregnancy scare can feel almost absurd to women in their 40s, unplanned pregnancies are not altogether uncommon in this age group. The reason for this is that a lot of women in this age group feel totally invulnerable to their own fertility. Somehow, the idea of getting pregnant at a time we are confronted with nearly daily reminders of our aging seems too cruel to be possible. Unfortunately, it’s not. Although women’s fertility declines as they approach middle-age, pregnancy is still possible. And the risk of complications from pregnancy and childbirth increase as women get older, women in their 40s can have a lot more to lose when it comes to unexpected pregnancies than women in their 20s. So, the pill’s pregnancy prevention effects are a huge benefit to women in midlife who are hoping to avoid the complications of an unwanted pregnancy at a time in their lives when the risks of such a pregnancy are particularly high.

There are also other perks that come from being on the pill during midlife. For example, many women find that pill use can help relieve some of the symptoms associated with perimenopause, such as cycle irregularity and hot flashesCombination pills containing both estrogen and progestin seem to offer women the greatest symptom relief. These symptoms occur because of hormonal imbalances that can occur across the cycle as women age. The pill – because it keeps women’s own levels of sex hormones low and replaces them with a consistent daily dose of synthetic hormones  – can help manage these symptoms. Although the pill does not address the cause of these symptoms (it does not address any of the underlying issues that create the hormonal imbalances at the root of these symptoms), it can provide women relief from them. 

The pill has also been found to offer symptom relief to women who experience severe PMS or PMDD (premenstrual dysphoric disorder – a more serious form of PMS).  PMS and PMDD symptoms – which manifest themselves as a combination of physical and psychological effects, such as mood changes, irritability, and physical discomfort – are believed to be caused by abnormal physiological responses to changing levels of hormonesacross the cycle. By ironing out the hormonal fluctuations that occur across the cycle and lifespan, the pill can take the edge off PMS for women whose brains and bodies don’t respond well to hormonal ups and downs. This is particularly true of brands that use the same dose of hormones throughout the cycle (monophasic treatments) or those that keep you on a steady dose of hormones for three months before you have your week of placebo pills. Estrogen containing pills are also known to reduce women’s risk of endometrial and ovarian cancer, and may even offer some protection against colon cancer.

Now, for the drawbacks. Although research consensus tells us that midlife pill use is perfectly safe for most healthy, nonsmoking women 35 and older, it’s not for everyone. It can still be associated with an increased risk of serious cardiovascular events (like strokes and heart attacks) in women who smoke, are obese, or have a personal health history that is known be associated with an increased risk of cardiovascular events (e.g., migraine with aura or diabetes). It is generally recommended that these higher-risk women avoid estrogen containing products, since estrogen use is linked with an increased risk of cardiovascular events; however, progestin only formulations canoften be safely. You will need to talk with your doctor about whether it makes sense for you, given your unique personal and health history.

It’s also worth noting that we don’t yet know a whole lot about what it means for women to be on a more-or-less steady dose of hormonal contraceptives for decades at a time. How does this change women’s bodies? And brains?

There is a growing body of research in psychology and neuroscience that finds that the birth control pill can  number of effects of the activities of the brain. For example, research indicates that the pill can influence the psychological processes involved in sexual attraction and partner preferencesthe desire for sexthe nature of the stress responselearning and memorymoodsuicide risk, and learning and memory. Accordingly, women of all ages on the birth control pill will want to keep track of how they are feeling, psychologically, as well as physically to determine whether the birth control pill is the right choice for them. Keeping a journal of your physical, as well as psychological, symptoms before and after starting hormonal contraception can be a useful tool to help determine whether birth control pill use is right for you.  

Although birth control use is a safe and effective means of regulating fertility for healthy women 35 and over, it is important to understand that there are questions that still remain. For example, we don’t know whether women 35 and over need the same doses of hormones needed by younger women to regulate fertility. We also don’t know what doses of estrogens and progestins are least likely to cause cardiovascular or metabolic issues, which tend to be of greater concern to women 35 and over.

Women in midlife need to be proactive about regulating their fertility up until they have stopped having menstrual cycles for two years or reach age 55, when natural sterility is assumed. If you are a healthy non-smoking woman, the birth control pill can be part of this strategy until birth control is no longer needed.  

What does the pill’s effect on the human stress response mean?

Photo by energepic.com on Pexels.com

The birth control pill has been life-changing for generations of women. It has allowed us to dream bigger and achieve more than even the most optimistic feminist would have ever dared imagine possible 60 years ago. Freeing women from the possibility of an unintended pregnancy has removed a powerful storm cloud that was perpetually present for our college-bound grandmothers and great-grandmothers. It allowed women – for the very first time in history – to plan. As a result of this freedom, there are now some 2.2 million more women enrolled in collegethan men, with women 30 and younger also being more likely than men to have earned a college degree

There is little doubt that, for many women (myself included), the pill is the most pivotal prescription they’ll ever fill. 

But just as we honor the spirit of democracy through the act of self-reflection and critical discussion, we need to continually push to get access to as much information as possible about this great emancipator of women. Women and women’s issues have almost completely been ignored for decades by medical research, which means that we know embarrassingly little research on the range of effects that the birth control pill can have on women’s bodies. And this particularly true when it comes to the impact of the pill on the brain and the stress response. 

Although many of us think of our stress response as being something to be avoided, it’s actually one of the unsung heroes of emotional and physical well-being. This is because it’s not our stress response that causes stress. Life causes stress. Our stress response is the way that our body copes with and manages the stress created by our crazy, overscheduled lives. The specifics of the stress response differ a little bit depending on what’s stressing us out (e.g., pressing deadline versus wildebeest stampede), but there are a few common ingredients that operate across pretty much all of them. One these ingredients is release of the stress hormone cortisol. Cortisol’s job is to dump fat and sugar into the bloodstream to allow for quick escape from dangerregulate inflammatory activity in preparation for injury, and potentiate brain cell activity to allow us to learnfrom our stressful experiences. Each of these activities is integral to our ability to adaptively respond to stress, so much so that we see it in virtually all healthy, functioning living organisms.  

Except for women on the birth control pill.

For almost three decades now, researchers have been documenting thatwomen on the birth control lack the cortisol response to stress.Pill-taking women exhibit higher than average levels of total cortisol, high levels of corticosteroid binding globulins (CBGs), and dysregulated responses to exogenously administered cortisol. And this is significant because these patterns are typically only observedwhen the body becomes so overwhelmed with cortisol signaling that it has no choice but to shut the signal downaltogether. For example, this type of pattern is often observed in children who have been abused or abandonedand those with a joint diagnosis of PTSD and major depressive disorder.We should all be alarmed by the fact that the stress hormone profiles of women who are on the birth control pill look more like those belonging to trauma victimsthan they do like those belonging to otherwise healthy young women. 

So, why haven’t you heard about this before and what does it mean?

Although researchers have been documenting this effectsince the mid-1990s, the information isn’t widely known.  The problem goes back to the lack of research on women and the pill: rather than being the focus of inquiry into the psychological and neurobiological effects of the birth control pill, these patterns are often reported as footnotes in the margins of research about other things. So, these effects aren’t well-known among researchers, let alone the millions of women who are the birth control pill or even the doctors who prescribe it. This information is critical, though, to women’s health and well-being and may help solve some of the most vexing problems in women’s health. For example, disruptions in cortisol signaling are believed to underlie many neuropsychiatric disorders, including depression and anxiety, as well as metabolic disorders such as obesityand insulin resistance.

Although the precise impact of the birth control pill on each of these outcomes is currently not well-understood, its impact is likely to be significant. Already, stress dysregulation in the context of the pill has been linked to problems with learning,the ability to process negative emotions, and memory for emotionally-laden events. Others find that pill-taking women’s brainsand lipid profilesshow evidence of hippocampal shrinkage and elevated triglycerides, both of which are also linked to chronic stress. 

Your doctor isn’t going to tell you about this research. In fact, it’s unlikely that your doctor has heard about it before. In addition to being woefully understudied, the neurobiological and psychological effects of the birth control pill aren’t topics that most medical doctors consider to fall under the purview of medical practice. Most neuroscientists don’t read the results of medical research and most physicians don’t read research in neuroscience.

The pill will likely continue to be the best option for many women. However, we deserve to have access to the information that science gives us so that women can better monitor their health to make sure that their birth control pills are working for, and not against, their long-term health and well-being. 

It is estimated that only 2% of annual sales revenue from contraceptives gets funneled back into research and developmentof new and better ways to prevent pregnancy. That number is unacceptable and suggests that we have gotten far too complacent with the options that we currently have available. Doing better will require a significant investment in research on issues that are important to women, including the ways that the pill modifies women’s stress response. It will also require that we change the way that medicine is practiced, with doctors being more aware of the psychological effects of the drugs they prescribe. There may well be better versions of the pill to be created, but we aren’t currently innovating to find them.

There has been a 9% decline in pill usage in the US in the last fifteen years, reflecting women’s growing distrust of medical professionals who have minimized the extent of the pill’s side-effects. Understanding what the full range of these side-effects are – and being able to recognize and treat them – is a critical next step in regaining women’s trust in medicine and their birth control pills

This is re-posting of an article I published first on Medium.

All hail progesterone.

Progesterone ≥99% | 4-Pregnene-3,20-dione | Sigma-Aldrich


But, to get to the punchline, we’re going to have to go over a few terms that aren’t particularly user-friendly. The first is allopregnanolone, which is a neurosteroid that gets released when your body is metabolizing progesterone. The second is γ-aminobutyric acid [aka GABA], which is a neurotransmitter that slows the brain down and makes you feel ahhhhhhhhhh. And one of the reasons that I love progesterone so much is that allopregnanolone – its little metabolic freebie – stimulates GABAA receptors, which can do all kinds of cool stuff in the brain.

Now, this might not sound very exciting, but let me remind you that one of the big reasons that people do things like drink wine and take Xanax is for their potent GABAA receptor action. GABA receptor stimulation makes us feel relaxed. And that’s a feeling that most of us can really wrap our arms around, especially now. So, the idea that we can have our GABAA receptors stimulated by simply metabolizing progesterone – which our body needs to do anyway – is pretty awesome.

And I’m not the only one who thinks so. There is a growing body of research that shows that allopregnanolone – because of its amazing GABArific effects – has a number of therapeutic benefits for the brain. Here is a great review of this literature if you want to read more about the science. What this research finds is that allopregnanolone has potent anti-anxiety and anti-depressant effects, it makes it easier for people to fall and stay asleep, and it can be used effectively to treat seizures and symptoms of alcohol withdrawal.

Now, here’s where things start to get interesting. When you put this all into context, we can make some predictions that might be meaningful to you. First, we can predict that times in the cycle when progesterone is high (the luteal phase), women should feel less anxious and depressed, they should sleep better, and they should be less likely to get seizures or migraines (the neurotransmitter activity involved in both are very similar) than at points in the cycle when progesterone is low. We might even find that women with alcohol dependencies are better able to abstain from alcohol use during this phase of the cycle than during the follicular, ovulatory, or menstrual phase.

But what about women women PMS? Or PMDD? Don’t they feel worse during this phase of the cycle than they do at the others?

Yes. And it turns out that allopregnanolone and GABAA receptors have something to do with this, too. The research, which is summarized nicely in this review article, suggests that PMDD may be caused by impairments in the interaction between allopregnanolone and GABAA receptors. Although women without PMDD are able to dynamically adjust their numbers of functional GABAA receptors, allowing them to experience the amazingness that is GABAergic activity, women with PMDD aren’t so lucky. They aren’t able to adapt to dynamically changing levels of allopregnanolone across the cycle, which can result in mood problems and poor regulation of the stress response. This is why the birth control pill – which irons out women’s hormonal fluctuations and replaces them with a constant daily dose of synthetics – can be therapeutic to women with PMDD.

It is also interesting for me to think about what this means for women on the pill and women going through perimenopause / menopause. Given that women on the pill have extremely low levels of progesterone (and the synthetic progestins in the pill do not release allopregnanolone), we can predict that they will have a higher incidence of mood disorders, sleep disturbances, and might even have a harder time kicking alcohol dependencies than their naturally-cycling counterparts. And – as I talk about in my book – there is evidence for the first of these things, with the pill being associated with an increased risk of mood disorders. I am super-curious about the second two. I am currently plotting ways to include questions about these things in my upcoming research.

It’s also really interesting to think about this as it relates to perimenopause (which I am totally going to rebrand with a better name as soon as I think of one – the word perimenopause feels totally unacceptable to me). During this hormonal transition, our hormone levels drop, which wreaks all kids of havoc on the body and brain. And among the havoc it wreaks is that it makes women angry, anxious, and depressed. It seems likely that changes in GABAergic activity resulting from diminishing levels of progesterone could have something to do with this… and research suggests it may. If you are perimenopausal and pissed off, it’s not your imagination. You may be seriously lacking GABAergic activity, which can make you anxious, angry, sad, and more likely to want that glass of wine to help take the edge off. It doesn’t need to be this way. I recommend talking to your doctor or naturopath about if you think your mood-related woes may be linked to low progesterone. She may recommend supplementing with bio-identical progesterone or trying one of the non-hormonal GABA hacks below.

The good news is that there are ways that we can increase GABAergic activity on our own. Exercise, meditation, yoga, eating fermented foods with probiotics (or kombucha! which is my favorite non-wine-based way to feel GABArific), and supplementing with magnolia bark, valerian root, or lemon balm. Each of these recommendations are backed by research and worth exploring if you think you could benefit from some additional GABA-related action in your life.

The latest on hormonal contraceptives and weight gain (new data are in!)

As you might imagine, I love talking to women about their experiences with hormonal contraceptives. And given my penchant for nerding out on details that others might find TMI (“…did your orgasms return to normal once you switched the brand you were on??”), I find myself talking to women about these experiences a lot. Like, A LOT, a lot. And one of the things that women most-often ask me about in these discussions is whether their hormonal birth control might be causing them to gain weight. Because many women swear that they gain weight on the pill, even when their doctors tell them otherwise.

But that conversation may be changing soon.

To start with, women’s doctors haven’t been lying to them. For a really long time now, the majority of studies that have set out to look at the relationship between hormonal contraceptive use and weight gain have found no relationship between the two. There have been some exceptions to this (I’m looking at you, hormonal contraceptive shot), but most studies fail to find a relationship between being on hormonal contraceptives and weight gain. This, of course, begs the question of why science hasn’t been able to document pill-induced weight gain when so many women report that this is what happened to them.

One possibility is that women are simply mistaking weight gained for others reasons on their birth control. It’s easy and convenient to blame our birth control for any problems we might have (although, please note that I have learned the hard way that the IRS will not accept “unusual birth control side effect” as an acceptable explanation for late taxes). So, it’s possible that women are misattributing regular, run of the mill weight gain to a birth control issue.

Another possibility is that some women *are* gaining weight on their hormonal birth control, but that science just hasn’t been able to capture it yet. This is the sort of thing that can happen when a medication impacts different people in different ways. Which of course it will. I talk about this issue a lot in my book. No two of us are built the same way, which means that each of us might respond to the exact same medication in very different ways. Especially something that influences sex hormones. This is why you should always listen to what your body is telling you. If you are experiencing a side effect that isn’t described in the package insert of your birth control, there’s a pretty good chance that you aren’t imagining things. Science probably just hasn’t been able to capture your weird side-effect yet because not everyone has it. Thankfully some new research is finally beginning to underscore this super-important point by showing gene-based differences in the risk of weight gain from the birth control implant.

In a new study that is in press in the research journal Contraception, researchers found that women who went on the birth control implant (which uses the third-generation progestin etonogestrel), at the time of the study, had gained an average of seven pounds since the time it was inserted (roughly two years prior). This is significantly greater than the average two-year weight gain found among women in the absence of implant insertion. More interestingly than that, though, was what they found next. Women who had two copies of the ESR1 rs9340799 variant of the estrogen receptor gene gained, on average, gained 30.8 pounds more than all other participants after going on the birth control implant.

Taken from Lazorwitz et al., in press. Note that the Y-axis shows weight as kg (instead of pounds).

This is huge. And it’s huge for a couple of reasons that may be meaningful to you even if you have no intention of ever going on the birth control implant.

The first reason that these results are pretty huge is because this study found that being on the birth control implant, for all of the women in their study, was associated with an increase in weight over time. Although most women gain a little bit of weight over time, regardless of how they are preventing pregnancy, seven pounds over two years is greater than what would be expected in the absence of a manipulation (here: the birth control implant). So, the implant appears to be associated with an increased risk of weight gain for all women.

The second thing that is a big deal is that how women responded to the implant depended on their genes. Women with the ESR1 rs9340799 variant of the estrogen receptor gene were likely to gain a whole lot more weight after going on the implant that were women with other genetic variants. Like, THREE TIMES more. This is important for a lot of reasons. First, it provides evidence that women can respond very differently to the exact same type of hormonal birth control. And this includes differences in the likelihood of gaining weight from being on it. Science has finally heard you. Some women will gain weight on the pill. Some women will lose weight on the pill. And some women will experience no changes whatsoever. And one of the factors that influences which camp you will fall into is your genes.

However, the biggest deal with this is research is that it has begun to expose the tip of the iceberg. This is one genetic SNP and one type of birth control. Imagine how many unidentified risk factors for unpleasant side effects (including weight gain) each one of us has latent in our genomes. There are probably side effects that you are vastly more likely to get than others because of your genes. And there is a chance that the existing research literature – most of which doesn’t look at gene-based differences in responses to birth control at all – doesn’t yet know about it. You aren’t crazy. You aren’t imagining things. It could be your birth control.

I am so excited about this next phase of research on the birth control pill. And I am excited that my lab and the research we are doing gets to be part of it. I look forward to seeing you all, your daughters, and my daughter being given access to better, more targeted means of fertility regulation.

Take care and be well.

PS: If any of you are interested in learning more about your genes and which ESR1 gene you have, you can actually download the raw data from your entire genome from 23 and Me. From there, you can dig around in your own genome to find our what you are made of.

Birth control pills & partner choice.

Is sexy in the eye of the pill-taker?

If you’ve ever had to suffer through an awkward middle school health class, there’s a good chance that you’ve probably heard about all the stuff that estrogen does from the neck down to promote reproduction. A little follicle stimulation here and a little endometrial lining proliferation there. However, there’s a piece of the puzzle you probably haven’t heard much about that is just as important to the process of reproduction as is the release of an egg: sex. And sex requires a partner. So, estrogen – in addition to all of the things that it does to make conception possible – may also have a hand in partner choice. And there’s a growing body of research in psychology that suggests that this is exactly what goes on.

Research conducted on heterosexual women finds that, as estrogen increases across the cycle, so too does women’s sexual desireand attunement to cues of good genetic quality in men. In particular, this research finds that estrogen increases women’s preference for men whose facesvoices, and behaviorsexhibit cues to the presence of relatively high levels of the male sex hormone, testosterone (we’re talking square jaws, deep voices, and swagger). This research also finds that estrogen tends to heighten women’s preference for the scentof men who possess testosterone markersand whose faces and bodies are symmetrical. Estrogen increases attunement to these qualities (and makes them more desirable to women) since each of these cues are reasoned to be indicators of high genetic quality in men, which is something that would have led to more successful pregnancies and more surviving children. 

Now, it’s important to note that the overwhelming majority of this sort of research has been conducted exclusively in heterosexual women [yawn]. This means that we can’t be absolutely certain that these shifts characterize allwomen. However, there is every reason to believe that LGBTQI+ women will experience similar shifts in mating psychology in the presence of estrogen. Research suggests that the mating psychology of gay and transgendered women isn’t all that different from that of their heterosexual, cisgendered peers. And given how estrogen works, there is every reason to believe that it will impact all women’s partner preferences in similar ways, regardless of whether it is occurring as the result of an egg follicle maturing (which is what happens to women with ovaries) or a prescription medication.  

Which brings us to the birth control pill.

Given everything that estrogen does to impact women’s desire for sex and partner choice, it probably shouldn’t be hugely surprising that the pill can have some pretty sweeping effects on women’s sexual and mating psychology. And the research suggests that it does. In addition to being linked to decreased sexual enjoymentand increased risk of sexual dysfunction, research suggests that the birth control pill may also change women’s partner preferences…and in ways that may have implications for their relationships in the long-term. 

For example, in one studythat was conducted on a sample of 55 women, researchers had women use a special computer program to manipulate the appearance of photographs of male and female faces. Clicking on a computer mouse allowed them to masculinize or feminize the facial prototype, which they were asked to manipulate to look like their ideal short-term or long-term romantic partner. After their first laboratory session, half of the women in their study started taking the birth control pill and the other half did not. Both groups of women came back to the lab three months later and completed this task a second time.

When the researchers compared the two sets of images created by the non pill-takers, they found no differences between the faces they created at time one and time two. However, for the women who started the pill, they found that women’s ideal male faces became significantly less masculine after the fact. A follow-up study of pill-taking women’s actual partner choice echoed these results. Using a sample of 170 age-matched, partnered women, researchers found that the faces of men who were chosen as partners by women who were on the birth control pill had significantly less masculine faces than those of their non pill-taking contemporaries. 

These differences can potentially have important implications for women’s relationship satisfaction. For example, in one studyconducted on 2,519 women, researchers compared ratings of relationship quality given by women who had chosen their partners when they were on the pill to those given by women who had chosen their partners when they were not on the pill. They found that women who had chosen their partners when they were on the pill reported less sexual attraction to their partners, less sexual arousal in response to their partners, and less sexual adventurousness than women who had chosen their partners when they were not on the pill. Later longitudinal studiesfound similar patterns. After following two samples of married couples (one sample was comprised of 48 couples; the other 70 couples) for up to five years,  they found that women who chose their partners when they were on the pill and then went off of it experienced changes in sexual and relationship satisfaction in response to their change in hormonal status. Specifically, they  found that all of these women reported decreased sexual satisfaction after going off the pill. And for women who were paired to unattractive husbands? They found that this change was accompanied by a decrease in overall marital satisfaction. 

The results of these studies suggest that the pill – by influencing who women are attracted to – may have important implications for women’s relationships. Given that pill-taking women don’t exhibit the preference for cues to testosterone are observed in naturally cycling women, there’s a chance that a partner chosen on the pill – when women prefer rounder, more feminine faces than what is observed in non-pill-takers – may not meet a woman’s masculinity standards once she goes off the pill. 

As unsettling as this interpretation may be, it is consistent with what research tells us about the effects of estrogen on mate preferences. It is also consistent with stories that I have heard from women about their transition off of the birth control pill. Although many women are able to transition off of the pill without having any major relationship disruptions, this isn’t true for others. As a research psychologist, I have had the opportunity to collect data – both in the form of surveys and interviews with women – about their experiences on and off of the birth control pill. In the process, I have spoken to several women who have had no issues with their partners whatsoever in their transition on and off the birth control pill, but also many for whom it proved very disruptive. In some, it was disruptive because they found that being off of it decreased their attraction to their partner. In others, it increased their attraction to other men. In others yet, it did both. In many of these cases, the relationship with their partners ultimately ended, which is a heartbreaking thing to have happen in response to changes in a medication. 

The idea that your birth control pill might influence your choice of relationship partners in a way that that could mean trouble down the road might sound a little scary. But take heart in knowing that this doesn’t happen to all women. It’s also worth keeping in mind that relationships are always scary. The pill just adds a new wrinkle into the mix. And there is a lot that we still need to know. For example, are all birth control pills equally likely to have an impact on partner choice? And how doesthe pill impact the partner preferences and choices of women in LGBTQI+ relationships? Although there is every reason to believe that the impact of the pill on the brain should operate very similarly across people, regardless of sexual identity or orientation, we need more research to know for certain whether this is true.

Lastly, it’s worth point out that beingon the pill when you choose your partner may increase your risk of some types of relationship problems, but it dramatically decreases your risk of others. For example, being on the pill decreases women’s risk of needingto get married out of financial necessity or because they got pregnant unexpectedly. It also grants women the opportunity to take their time in finding the right partner and allows them to meet their career goals and be less financially dependent on men. Both of these things increase women’s ability to find satisfying relationships. Knowing what the pill does when it comes to choosing men means that you get to choose who you want to be and what you prioritize in your partner. And that’s empowering. Whether you are on the pill or off of it, you get to pick what happens next. 

This Is Your Brain on Birth Control by Dr Sarah E. Hill is published by Avery, out now.