Restless legs syndrome is a neurological condition that creates an almost irresistible urge to move your legs — usually accompanied by an uncomfortable crawling, tingling, or pulling sensation — that appears when you are at rest and gets worse in the evening. Moving relieves it briefly, which is exactly why it wrecks sleep: the one thing your body needs to do to fall asleep (stay still) is the one thing that triggers the sensation. If you have ever felt like your legs “won’t let you” drift off, this is likely what you are experiencing, and it is far more common than most people realize — especially during pregnancy, the postpartum window, and perimenopause.
What does restless legs syndrome actually feel like?
The sensations are notoriously hard to describe, which is part of why RLS goes underdiagnosed for years. People reach for words like crawling, creeping, itching-but-deeper, fizzing, pulling, or an electric restlessness. It usually sits deep inside the calf or thigh rather than on the skin. The defining feature is not the sensation itself but the response it demands: an overwhelming urge to move. Stretch, walk, jiggle, kick — and the feeling eases for a moment, then returns the instant you go still again.
Clinicians recognize RLS by four hallmark features: an urge to move the legs, usually with uncomfortable sensations; symptoms that begin or worsen during rest; relief through movement; and a clear circadian pattern where things are worst in the evening and night. That last point matters enormously — RLS is not just “twitchy legs,” it is a condition timed almost perfectly to collide with the hours you are trying to fall asleep.
Why does it get worse at night?
RLS follows your body clock. Symptoms are mild or absent in the morning and intensify as evening arrives, peaking in the hours around your usual bedtime. This is not a coincidence of tiredness — it tracks the daily rhythm of dopamine, the brain chemical most implicated in RLS. Dopamine activity naturally dips in the evening, and in people with RLS that dip appears to unmask the symptoms.
The underlying mechanism connects two systems: iron and dopamine. In their foundational review in Movement Disorders (Allen & Earley, 2007), researchers described how the brain in RLS shows a deficiency of iron specifically in the regions that regulate movement — even when blood iron levels look normal. Iron is a required cofactor for the enzyme that produces dopamine, so low brain iron leads to disordered dopamine signaling in the circuits that control the legs. The circadian evening dip in dopamine, layered on top of an already iron-strained system, is why symptoms crescendo at exactly the wrong time. This is also why RLS overlaps with the frustrating experience of being exhausted but physically unable to settle.
Why is RLS so common in pregnancy and postpartum?
Pregnancy is one of the strongest known triggers for restless legs syndrome. A systematic review and meta-analysis in Sleep Medicine Reviews (Chen et al., 2018) pooling data across dozens of studies found that roughly 21% of pregnant women experience RLS — climbing from about 8% in the first trimester to 22% in the third. That is more than double the rate in the general population.
The reasons fit the iron-and-dopamine model precisely. Pregnancy dramatically increases iron demand as blood volume expands and the growing baby draws on maternal stores, which can leave the brain’s iron reserves stretched thin. Folate demand rises too, and both nutrients are tied to the dopamine pathway. Hormonal shifts — particularly the surge in estrogen across pregnancy — appear to modulate symptoms as well. Reassuringly, the same meta-analysis and related work show that for most women, pregnancy-related RLS resolves quickly after delivery, with prevalence dropping sharply in the weeks postpartum.
But “resolves after delivery” does not mean the sleep damage disappears. A new parent who spent the third trimester unable to fall asleep because of restless legs enters the newborn period already carrying a significant deficit — and then layers severe sleep fragmentation from night feeds on top. If RLS persists into the postpartum months, it is worth having iron levels checked, because postpartum iron depletion (especially after significant blood loss at delivery) is common and treatable.
Why does RLS flare in perimenopause?
For women in their 40s and 50s, restless legs can appear or worsen for the first time, and the hormonal transition seems to be part of why. In a population study of 5,000 Swedish women published in Climacteric (Wesström et al., 2008), 15.7% were diagnosed with RLS, and prevalence rose with age. Notably, the study found a strong association between vasomotor symptoms — the hot flashes and night sweats of the menopause transition — and restless legs, suggesting the two share hormonal roots.
The leading explanation is again dopamine. Estrogen appears to support healthy dopamine signaling, and the erratic decline of estrogen through perimenopause may destabilize the same pathway that RLS depends on. It may be the fluctuation rather than the absolute level that matters — which is consistent with why RLS often first shows up during hormonally turbulent windows (pregnancy, perimenopause) rather than during stable ones. Iron matters here too: heavy or irregular perimenopausal periods can quietly lower iron stores over months, tightening the same constraint that drives RLS in pregnancy.
For perimenopausal women, RLS rarely arrives alone. It tends to stack with the early-morning waking and fragmented nights already characteristic of the transition, which is why the cumulative toll on sleep can feel disproportionate to any single symptom.
What actually helps restless legs at night?
The evidence points to a few consistent, low-risk starting places. None of this is medical advice — RLS that meaningfully disrupts your sleep is worth a conversation with a clinician, particularly to check iron — but these are the levers research supports.
Get your iron checked (specifically ferritin). Because RLS is tied to iron availability, a blood test for serum ferritin is the single most useful first step. Many clinicians treat RLS with iron supplementation when ferritin is low or even low-normal, and correcting a deficiency can substantially reduce symptoms. This is not something to self-dose blindly — excess iron is harmful — so it belongs with a lab test and clinical guidance. For pregnant and postpartum women in particular, this is the highest-yield check.
Move the way that helps, not the way that hurts. Gentle, regular daytime activity is associated with fewer RLS symptoms, while intense exercise late in the evening can make them worse for some people. A walk, light stretching, or leg movement earlier in the day tends to help; a hard workout right before bed can backfire. The broader relationship between physical activity and sleep quality reinforces the same timing principle.
Mind the evening triggers. Caffeine, alcohol, and nicotine are all commonly reported to worsen RLS, and the effect can be pronounced in the hours before bed. Certain medications — including some antihistamines, anti-nausea drugs, and older antidepressants — can also aggravate symptoms, so it is worth reviewing anything new with your prescriber if RLS started or worsened after a medication change.
Consider magnesium, with realistic expectations. Magnesium is frequently suggested for restless legs and nighttime muscle discomfort. The evidence is thinner than for iron, but it is low-risk for most people, and some find it helpful. Our fuller look at what magnesium can and can’t do for sleep covers where the science is solid and where it is oversold.
Warmth, counter-stimulation, and rhythm. A warm bath, a heating pad, calf massage, or compression can provide temporary relief by giving the nervous system competing input. These are symptomatic tools rather than fixes, but on a bad night they can be the difference between lying awake fighting the urge and settling enough to fall asleep.
When should you take RLS seriously?
Occasional restless legs after a long day of sitting is not a disorder. It becomes something to address when it shows up most nights, reliably delays your sleep, or wakes you — because chronic RLS drives real, measurable sleep deprivation and its daytime consequences. It is also worth flagging to a clinician if symptoms appear suddenly and severely, if they are one-sided, or if they come with numbness or weakness, since those can point to other causes worth ruling out. And in pregnancy or postpartum, RLS is a specific prompt to check iron rather than to simply endure it.
The calm version
Restless legs syndrome is not restlessness of character or a failure to relax — it is a real neurological pattern rooted in how your brain uses iron and dopamine, and it clusters in exactly the life stages, pregnancy and perimenopause, where those systems are under the most strain. That means it is often explainable and frequently improvable, starting with something as simple as a ferritin test. Mendtide won’t diagnose RLS, but by helping you see how your nights are actually fragmenting — and gently flagging the patterns worth raising with a clinician — it keeps you focused on the next useful step rather than the number on a screen.
Your legs aren’t betraying you. They’re carrying a signal your nervous system is sending at the wrong hour — and signals, once understood, can usually be quieted.