Science

Hormones and desire, plainly: the month, the year, the decade

Hormones get blamed for almost every change in desire and credited with almost none of the good ones. Someone stops wanting their partner and a friend says it is probably hormones. Someone starts wanting their partner again and nobody says anything at all. The word has become a shrug, a way of ending the conversation rather than starting it, which is a shame, because the real picture is more useful than the shrug and not much harder to hold in your head.

This page is the hub for that picture. It lays out what hormones can and cannot do to desire, then walks the three clocks they run on: the month, which is the cycle; the year, which is pregnancy, birth, feeding, and the long recovery after; and the decade, which is the slow drift of midlife, perimenopause, menopause, and the gradual change in testosterone that both men and women go through. Each clock has its own page on this site, and this one tells you which clock you are probably looking at and where to read next. The frame throughout is observational. Hormones move the dials. They do not hold the pen.

What can hormones actually do to desire?

They change how easily the dials move, not what the dials are. The Dual Control Model, developed by researchers at the Kinsey Institute, describes sexual response as two separate systems: an accelerator that answers appealing input and a set of brakes that answer anything the body reads as a reason to hold back. Those two systems are the equipment. Hormones are more like the weather the equipment runs in. On some days the accelerator answers a small thing with a large response and the brakes stay quiet. On other days the same input gets a faint reply and every brake in the house is pressed. The equipment did not change between those days. The conditions did.

Health publishers describe estrogen, progesterone, testosterone, prolactin, and thyroid hormone as the ones that most visibly move desire, and the plain observation underneath all of them is the same: when the hormonal picture shifts, people report desire arriving more easily or less easily, the body feeling more like their own or less, and the ordinary brakes of tiredness, discomfort, and low mood pressing harder or softer. What hormones do not do is decide whether you love your partner, whether the relationship works, or whether you are a person who wants closeness. Those questions get asked when desire goes quiet, and the hormonal answer is almost always narrower than the question. Our page on what libido means covers why one summary word gets asked to carry so much. Hormones carry a real part of it. They do not carry the whole thing.

What does the month do?

For anyone who cycles, the month is the clock with the shortest hand, and the one most people have never been shown. Health publishers describe a stretch around ovulation when many people notice desire arriving more easily and a stretch in the days before a period when it tends to go quiet, with the week itself landing somewhere in between depending on comfort and mood. Our page on your cycle and desire describes the whole calendar and how to read it, and our page on PMS, PMDD, and desire covers the premenstrual week specifically, where soreness, bloating, tiredness, and a low mood that arrives on schedule press several brakes at once while the accelerator mostly waits underneath.

Two things sit on top of the month and change how it reads. Hormonal birth control steadies the cycle by design, and for some people that steadiness includes a flattening of the ovulation stretch, which our page on birth control and desire describes alongside the people who notice nothing at all and the people who find the predictability a relief. Coming off it is its own chapter, covered on our page about stopping birth control, where three outcomes are all reported and none is promised. And conditions that change the month from inside, such as PCOS and endometriosis, each have a page here, because a cycle that is irregular or painful lands on desire through the brakes long before it lands through anything hormonal. The useful move for the month is a calendar. Two cycles of noticing when desire arrives and when it does not turns a mystery into a forecast, and our page on tracking your dials describes how.

What does the year do?

The year is the pregnancy clock, and it is the one where hormones move furthest and fastest. Health publishers describe pregnancy as the highest-hormone state an adult body runs, and our page on desire during pregnancy walks the three trimesters as three different bodies: the first often flattened by nausea and exhaustion, the second frequently reported as a return or even a rise, the third pressed by size, discomfort, and the mind already living in the delivery room. Then birth ends that state within days, and estrogen and progesterone fall to some of the lowest levels the body sees. Our page on postpartum desire describes the timeline nobody explains at the six-week checkup, and our new page on intimacy after birth covers the gap between being cleared and being ready.

Feeding extends the year. Prolactin, the hormone behind milk production, holds estrogen down for as long as feeding continues, and many nursing parents describe desire staying flat until feeding tapers and then returning on its own schedule, which our page on breastfeeding and desire covers as the hormone chapter with an end date. Mood sits alongside all of this, and our page on postpartum mood and desire describes when the low stretch is more than tired and belongs with a clinician. The partner who did not give birth is on the same clock without the hormones, which our page on the non-birthing partner after a baby describes, and the whole household is on it, which our page on desire after kids covers. The point of the year is that it ends. Every chapter in it has a departure date, even when the date is further out than anyone wants, and a couple who knows that reads the quiet stretch as a season rather than a verdict.

What does the decade do?

The decade is the slow clock, and it runs for everyone. For women, health publishers describe perimenopause as the years when estrogen and progesterone begin to swing before they fall, often starting in the forties, with cycles that shorten or lengthen, sleep that breaks, flushes and night sweats, and a mood that will not sit still. Our page on perimenopause and desire describes those years as the stretch when the dials will not hold a setting. Menopause is the point after which the swings stop and the levels settle low, and our page on desire after menopause covers the after chapter: dryness and thinning tissue that press the comfort brake, covered in its own right on our page about dryness and desire, and the equally common report that desire did not leave at all once comfort was handled. Hormone therapy belongs in this chapter too, and our page on hormone therapy and desire lists the questions worth bringing to the appointment.

For men, the decade is testosterone, and the observation health publishers make is that it declines gradually from the thirties on rather than dropping off a cliff. Our page on testosterone and desire is deliberately titled as a question, is it low testosterone, because the number gets blamed for a great deal that sleep, weight, medication, drinking, and mood are actually doing, and our page on men's desire after 50 describes slower as something other than gone. The decade also reaches both partners at once in ways that are not strictly hormonal: our page on desire in midlife separates what actually changes from what gets blamed, our page on desire after 60 does the same for the next stretch, and our page on living with a partner in menopause is for the person on the other side of the bed. The decade's honest summary is that the equipment keeps working. The conditions change, the comfort brake needs more attention than it used to, and the couples who do best are the ones who update the plan rather than mourning the old one.

What about the hormones nobody mentions?

Thyroid is the one most often missed. Health publishers describe both an underactive and an overactive thyroid as capable of flattening desire, the first through fatigue, weight change, low mood, and feeling cold, the second through anxiety, a racing pulse, and sleep that will not settle. Our page on thyroid and desire calls it the quiet dial behind the dials, because the symptoms look like a dozen other things and a single blood test usually settles the question. Prolactin outside of feeding is another, raised by some medications and occasionally by other causes, and it is on the standard list a doctor runs when desire drops without an obvious reason. Our page on raising low desire with a doctor describes how to get that list run without the conversation getting lost.

Then there are the things that move hormones from outside. Medication is the big one, and our pages on medication and desire, antidepressants and desire, and GLP-1 medications and desire each describe a drug that treats one thing and moves other dials on the way through. Diabetes sits on desire through blood sugar, circulation, and nerves, covered on our page about diabetes and desire. Weight change in either direction moves testosterone, estrogen, sleep, and energy together, covered on our page about weight changes and desire. Sleep itself, especially the broken sleep of snoring and apnea, is where a lot of so-called hormonal desire loss actually lives, and our pages on sleep and desire and on snoring, apnea, and desire are the place to start before any blood test. None of these is a hormone in the way people mean the word. All of them move the hormonal weather, and most of them are more fixable than the weather is.

How do you tell which clock you are on?

Ask three questions in order. Does the change track the month, arriving and lifting with the calendar? Then it is the cycle, and the pages on the cycle and on the premenstrual week are where to read. Did it start with a pregnancy, a birth, or feeding, and has it been less than a year or two since? Then it is the year, and the postpartum, breastfeeding, and after-birth pages are the ones. Has it crept in slowly over a few years alongside sleep changes, flushes, cycle changes, or the plain arithmetic of age? Then it is the decade, and the perimenopause, menopause, testosterone, and midlife pages are the place. And if the answer is none of the above, a sudden drop with no clock attached, our page on sudden loss of desire walks the other list, which is mostly medication, mood, illness, and the relationship itself.

Whichever clock it is, the second half of the answer is never hormonal. Hormones change how easily the dials move. What is pressing the brakes and what is feeding the accelerator on any given evening is still the stress of the week, the state of the room, the last fight, the sleep you did not get, and the plain question of whether the two of you are still reaching for each other in small ways. Our page on stress and desire covers the first of those and our page on everyday warmth the last. The Vibotype quiz is free and takes five minutes each, and it reads your accelerator, your brakes, and your tempo, meaning whether desire tends to arrive first or build once things start. It does not read your hormones, and it does not need to. It reads the equipment the hormones are running through, and that is the part of the picture you can actually do something about this week.

Common questions

Which hormones affect desire the most?

Health publishers most often name estrogen, progesterone, testosterone, prolactin, and thyroid hormone. The plain observation is that shifts in any of them change how easily desire arrives and how hard the ordinary brakes of tiredness, discomfort, and low mood press. They move the conditions the dials run in, not the dials themselves.

Is my low desire hormonal or something else?

Ask whether it tracks a clock. A dip that comes and goes with the month points to the cycle. One that started with a pregnancy, a birth, or feeding points to the postpartum year. One that crept in over years alongside sleep and cycle changes points to the midlife decade. A sudden drop with no clock attached is more often medication, mood, illness, or the relationship, and a doctor can run the short blood panel that settles the hormonal part.

Can a blood test tell me why my desire changed?

It can rule a few things in or out, mainly thyroid, prolactin, and testosterone, and it is worth asking for when a drop has no obvious cause. It cannot measure how easily your brakes press or how strongly your accelerator answers, which is where most desire changes actually live. Bring the whole picture to the appointment, including sleep, mood, medication, and stress, so the number is read in context.

Do hormones affect men's desire too?

Yes. Testosterone declines gradually from the thirties on, thyroid problems flatten desire in anyone, and prolactin can be raised by some medications. The plain observation health publishers make is that the number gets blamed for a great deal that sleep, weight, drinking, mood, and medication are doing, so those get checked alongside it rather than after.

Keep reading

Find your type

Five minutes, free, anonymous.