HORMONAL SHIFTS: WHAT REALLY HAPPENS BEYOND THE FOURTH TRIMESTER
By Nicole Fuge
So, the fourth trimester has come and gone. You’re (somewhat) getting the hang of this whole motherhood thing. The newborn fog has definitely lifted and maybe—just maybe—you’re managing to drink your tea while it’s still hot.
But just as you start to feel like yourself again, your body throws you another curveball.
Because here’s the truth most don’t tell you: the postpartum period doesn’t end at 12 weeks. The recalibration continues. Your hormones are still finding their way. And you’re not broken, or behind … you’re simply still in it.
Let’s talk about what really happens next.
The fourth trimester is only the beginning
We hear a lot about those first 12 weeks after birth, the “fourth trimester”, as this sacred, intense stretch of change. And it is. But the idea that everything settles neatly by the three-month mark? That’s a myth.
For many women, hormonal shifts continue for months, sometimes even years. The postpartum period isn’t a single phase; it’s a spectrum. Your body is still recovering from pregnancy and birth, your endocrine system is adapting, and your hormones are responding to it all.
From fluctuating oestrogen and progesterone to thyroid shifts and breastfeeding hormones, your internal world stays on a kind of loop-de-loop for a while.
Hair loss, dry skin and breakouts
Around the three- to four-month mark, many new mothers notice their hair coming out in clumps. It can feel shocking, but it’s also completely normal.
During pregnancy, elevated oestrogen levels keep your hair in the growth phase. Once those levels drop, your strands shift back into their natural cycle, and that means mass shedding.
And your skin? It might feel like it’s suddenly forgotten how to behave. Dry patches, hormonal acne, eczema flare-ups, these can all be part of the ride, especially while breastfeeding, as oestrogen dips even further.
Mood swings and mental shifts
Here’s the part we don’t talk about nearly enough: postpartum mood changes.
The baby blues might peak early, but postnatal anxiety or depression can sneak in six, even 12 months later. Hormonal drops (particularly oestrogen and progesterone) can impact serotonin levels, making you more emotionally vulnerable. Add in the identity shift, the sleep deprivation, the invisible load, and it’s no wonder things feel wobbly.
If you’re feeling not-quite-yourself, you’re not alone. And it’s never too late to seek support. Your mental health matters—today, tomorrow, and long after the newborn stage has passed.
The breastfeeding effect
If you’re breastfeeding, prolactin and oxytocin are the hormones running the show. They support milk production and bonding, but they also suppress ovulation. That’s why some women don’t get their period for months (or even longer) postpartum.
While that might feel like a win, it also means your body is hanging out in a kind of hormonal limbo. Low oestrogen can affect mood, libido, skin, sleep, even your bones.
And when breastfeeding slows or stops? Cue another hormonal shift—sometimes subtle, sometimes stormy. PMS might hit differently. Your cycle might feel unfamiliar. Some women say it’s like going through puberty all over again.
Thyroid troubles
One of the quieter postpartum changes? The thyroid.
Postpartum thyroiditis affects around 1 in 20 women. It often goes undiagnosed because the symptoms—fatigue, anxiety, weight changes, brain fog—can feel a lot like typical new-mum exhaustion.
It usually starts with an overactive phase (hyperthyroidism), followed by a sluggish phase (hypothyroidism). If something feels persistently off, especially once you’ve moved past the early weeks, a thyroid check could offer answers. It’s a simple blood test, and it can be life-changing to get the right support.
The lesser-known shifts we don’t talk about enough
Crying at random things? Zero interest in sex? Boiling rage over someone breathing too loud? These aren’t just quirks. They’re often hormonal, and very real.
Oestrogen and progesterone influence serotonin, the mood-regulating chemical in your brain. So if you find yourself sobbing over a cotton commercial or feeling strangely hollow at nine months postpartum, it’s not just you being “emotional.” It’s biology.
Libido MIA? Low oestrogen, high cortisol, and sheer exhaustion form a trifecta that makes desire feel a million miles away. There’s nothing wrong with you. You are not broken. You are in recovery.
Postnatal rage—though less discussed—is another common experience. It’s fuelled by sleep deprivation, hormonal changes, and the mental load that seems to fall squarely in your lap. If you’ve ever shouted at the kettle for taking too long to boil, you’re not the only one.
Even your internal thermostat is recalibrating. Night sweats, hot flushes, chills, they’re all part of the postpartum hormonal symphony.
The slow return to something like “normal”
There’s no magic date for when your hormones settle. For some, it’s a few months. For others, it might take a year, or longer. And the truth? Your “normal” might not look like it used to.
But that doesn’t mean you’ve lost yourself. You’re still in there—wiser, softer, stronger, and slowly re-emerging.
So, be gentle with yourself. Nourish your body. Ask for help. Let the non-essentials wait. Honour the work your body continues to do, long after the birth.
keep the conversation open
Motherhood remakes us, inside and out. And the more we talk about the unseen, unglamorous parts—the skin changes, the sweats, the silent mood swings—the more seen we all feel.
So if you’re still crying over dog food commercials at eight months postpartum…
If your skin suddenly hates you…
If your libido has packed its bags and moved to another galaxy…
It’s not just you. It’s your hormones. And you are so not alone.
MUSE PAPER
ISSUE 04
Disclaimer: The content provided on Muse Paper is intended for informational and educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of your physician or other qualified healthcare professional with any questions you may have regarding your health, medical conditions, or treatments.