Restless Legs in Pregnancy

What restless legs syndrome actually is

Tommy's defines it as "a condition where you have a strong urge to move your legs, usually when resting at night." The NHS describes "a strong need to move your legs" alongside "uncomfortable feelings in your legs, such as tingling, throbbing or itching", which get worse at night and disrupt sleep.

Tommy's is more specific about the sensations people report: tingling, burning, itching and crawling. They are "often worse just below the knee", though they can affect the thighs, feet and sometimes the arms. The pattern that defines the condition is that the sensations come on at rest and ease when you move. That is what separates it from cramp, from ordinary fidgetiness, and from a leg that has simply gone numb.

It is a recognised neurological condition. It is not a habit, a nervous tic, or something you are doing to yourself.

How common it is, and when it starts

Tommy's reports that around 1 in 5 pregnant women and birthing people develop restless legs syndrome, and that it "usually occurs during the third trimester (the last 3 months of pregnancy)". Its page on common health problems says the same: "Some people get restless legs syndrome in pregnancy, usually in the third trimester."

So if it appeared at around 28 to 32 weeks and you have never had it before, that is the textbook presentation rather than something unusual.

Why pregnancy brings it on

The honest answer is that it is not fully understood, but there are two established links.

Iron and dopamine. Both Tommy's and the NHS say the condition is thought to be linked to levels of iron and the brain chemical dopamine in the body. The NHS lists iron deficiency anaemia among the conditions associated with restless legs, and Tommy's notes that iron-deficiency anaemia can trigger symptoms.

Pregnancy itself. Tommy's says it "can be brought on by pregnancy in people who have never had it before", possibly because of hormonal changes. The NHS lists pregnancy among the recognised associated conditions.

The iron link is the practically useful one, because it is testable. If you also have unusual exhaustion, breathlessness or pallor, that is worth mentioning — Tommy's advises consulting your midwife if extreme tiredness persists, because iron deficiency may need testing, and it notes that iron supplements help if anaemia is present.

What it is not: leg cramps

These get conflated constantly and they are different problems with different management.

The NHS describes cramp as "a sudden, sharp pain, usually in your calf muscles or feet. It's most common at night." Tommy's says leg cramps are "sudden, sharp pains, usually in your lower leg", and suggests stretching the leg and moving the ankle up and down during a cramp, with gentle stretches and not pointing your toes down while lying down to help prevent them.

Restless legs is an urge and an uncomfortable sensation relieved by movement. Cramp is a painful involuntary muscle contraction. If you are trying to work out which you have: cramp stops you moving; restless legs makes you move.

The distinction matters because the supplements often recommended for cramp do not have good evidence behind them. The Cochrane review of interventions for leg cramps in pregnancy identified eight randomised trials with 576 women between 14 and 36 weeks, comparing magnesium, calcium, calcium-with-vitamin-D or vitamin B against placebo or no treatment, and vitamin C against calcium. Its conclusion: "It is unclear from the evidence reviewed whether any of the interventions provide an effective treatment for leg cramps." The certainty of evidence was low or very low, and the reviewers noted that because adverse outcomes were mostly not reported, "it is therefore not possible to assess the safety of these interventions."

What actually helps

A caveat before the list: there is no equivalent pooled trial evidence for restless legs in pregnancy, and even the leg-cramp review above could not identify an effective treatment. What follows is national-guidance advice. It is low-risk and worth trying; it is not proven.

• Move when it starts. Both the NHS and Tommy's note that symptoms ease with movement — walking about or stretching your legs during an episode is the immediate answer.
• Regular exercise during the day. Tommy's suggests swimming; the NHS advises exercising daily.
• Heat. Tommy's lists heat pads and warm baths; the NHS lists applying heat.
• Massage and relaxation techniques (Tommy's).
• A consistent sleep schedule and a good bedroom environment (NHS).
• Ask about iron. Tommy's notes iron supplements help if you are anaemic. Do not start iron on your own — it needs a blood test first, and taking iron you do not need is not harmless.

What to cut back on

• Caffeine. Tommy's advises staying under 200 mg a day; the NHS suggests avoiding caffeine after midday.
• Alcohol. Tommy's says avoid it entirely.
• Smoking. Tommy's advises quitting.
• Heavy late meals and screens before bed (NHS).

Medicines

Tommy's is direct: "Medication for restless legs syndrome is not really recommended during pregnancy or while you are breastfeeding." The NHS lists treatments including pregabalin, gabapentin, codeine or tramadol, sleeping tablets and dopamine agonists such as ropinirole — but those are options for restless legs in the general population, not a menu for pregnancy. Do not start any of them without a specific conversation with your doctor.

When to call

Speak to your midwife or doctor if:

• Leg symptoms are disturbing your sleep (Tommy's lists this specifically for cramps).
• You have numbness or swelling in your legs (Tommy's).
• Cramps last longer than 10 minutes (Tommy's).
• You are exhausted beyond what your sleep loss explains — ask about an iron test.

Contact a doctor urgently if the problem is in one leg only, particularly if one calf is red, hot, swollen or tender. The HSE lists "one of your calves is red, swollen and hot" among the reasons to contact your midwife, GP or obstetrician immediately, and Tommy's treats unexplained one-sided leg swelling as a possible deep vein thrombosis and a medical emergency. Restless legs is symmetrical and sensory; a hot, swollen, painful single calf is a different problem entirely.

Call your local emergency number (999 in the UK and Ireland, 911 in the US and Canada, 000 in Australia, or 111 in New Zealand) if you develop sudden breathlessness or chest pain alongside a painful swollen leg.

When it ends

Tommy's: "If your symptoms are caused by pregnancy, it's likely that they will go away soon after giving birth." The NHS says the same — symptoms usually go away after giving birth. That is a genuine and well-established piece of reassurance, and it is worth holding on to during the weeks when it is at its worst.