The mucus plug is a thick, jelly-like seal in the canal of your cervix, and in the last weeks of pregnancy it comes away as the cervix softens. Some women find it on the toilet paper in one sticky blob. Others lose it a little at a time and never notice. The NHS calls the blood-streaked version a show, and says that sometimes there is no show at all.
This guide covers what the plug is for, what it looks like by colour, how to tell it from ordinary discharge and from your waters breaking, what it does and does not tell you about the start of labour, and the situations where it means a phone call today.
The short answer. The mucus plug is thick, stringy, jelly-like mucus, clear, off-white, pink or brown, often streaked with a little blood. After 37 weeks, losing it is normal and means your cervix is getting ready, but labour can follow within hours or not for days or weeks. Call the same day if it happens before 37 weeks, or straight away if you see bright red bleeding.
What the Mucus Plug Is
Early in pregnancy, rising progesterone thickens the mucus in your cervical canal until it forms a plug. The plug sits between the vagina, which carries bacteria, and the uterus, where your baby grows. Laboratory work on plugs collected from pregnant women shows that it does more than block the opening: it carries antimicrobial proteins and immune cells. A 2014 study by Hansen and colleagues found that the plug slows bacteria moving up from the vagina without stopping them completely, so it is one layer of protection, alongside the membranes around your baby.
Near term the cervix softens, thins and starts to open, and the plug loosens. Sex and internal examinations can loosen it too. The cervix keeps making mucus, so the plug can partly re-form after you lose some of it.
What It Looks Like, by Colour
Cleveland Clinic describes the plug as stringy, sticky and jelly-like, roughly 2.5 to 5 cm long and one to two tablespoons in volume, and relatively odourless. It may come out in one piece or as several smaller ones. If you are unsure, note the colour, the amount and the texture; your midwife will ask about all three.
| What you see | What it usually means | What to do |
|---|---|---|
| Clear, whitish or off-white jelly | The plug without blood | After 37 weeks: nothing urgent, mention it. Before 37 weeks: call today |
| Pink, or streaked with red | A "show": mucus mixed with a little blood from the softening cervix | After 37 weeks: normal, watch for contractions. Before 37 weeks: call today |
| Brown or brownish streaks | Older blood, often after an internal exam, a sweep or sex | Usually fine at term; mention it at your next contact |
| Bright red blood, more than a streak, or clots | Bleeding, which the plug does not explain | Call your maternity unit now |
| Green, yellow or grey, or a strong smell | Not the plug: possible infection, or stained waters if it is watery | Call today; call now if it is watery |
Cleveland Clinic puts the usual amount of a bloody show at no more than a tablespoon or two. The NHS is direct about the rest: if you are losing more blood than a streak, it may be a sign that something is wrong, and you should call your midwife immediately.
Mucus Plug, Discharge or Waters?
All three can leave your underwear wet in late pregnancy, and they mean different things. Normal pregnancy discharge increases steadily for months; the plug arrives as a lump of jelly; and your waters keep coming.
| Normal discharge | Mucus plug | Waters | |
|---|---|---|---|
| Texture | Thin, milky, creamy | Thick, stringy jelly that holds its shape | Watery, runs |
| Colour | White or clear | Clear, off-white, pink or brown-streaked | Clear or pale straw |
| Amount | A steady little every day | One or two tablespoons, at once or over days | A gush, or a trickle that keeps coming |
| Pad test | Damp patch, then dry | A blob on the pad, then dry | A fresh pad soaks again |
| What to do | Nothing, unless it smells or itches | See the colour table | Call your maternity unit |
If you cannot tell. Put on a clean pad and lie down for twenty to thirty minutes, then stand up. Fluid that runs again is probably your waters, and our guide to water breaking covers the colours and the 24-hour clock that follows. A pad that stays dry points to the plug or ordinary discharge.
How Long Before Labour?
The plug is a poor clock. The NHS says labour may follow quickly or may take a few days. Cleveland Clinic says some women go into labour within hours or days and others not for a few weeks. MedlinePlus notes that active labour may still be days away when you see bloody or brownish mucus. None of these sources gives an average gap, because the spread is too wide for one number to help you.
The plug tells you that your cervix has started to change. Contractions tell you that labour has started. Use the second, and keep the full list of signs of labour to hand, from the baby dropping to the 5-1-1 rule.
After a membrane sweep or internal exam
After 39 weeks you may be offered a membrane sweep, where your midwife or doctor runs a finger around the cervix during an internal examination. The NHS lists cramping and some vaginal bleeding afterwards as expected, and a sweep or exam often loosens part of the plug. Pink or brown mucus in the next day or so is common and does not mean labour is starting. The sweep and what follows it are covered in our guide to going past your due date.
Before 37 Weeks, Call the Same Day
Losing the plug before 37 weeks is a different situation. Cleveland Clinic advises contacting your provider as a precaution whenever it comes away early, because a change in discharge or mucus can be an early sign of preterm labour. Call the same day, and sooner if you also have regular tightenings, period-type pain, a new low backache or any leak of fluid, which the NHS lists as signs of premature labour.
What to Do Next at Term
After 37 weeks, with streaked mucus and nothing else
- Note the time, the colour and roughly how much
- Wear a pad so you can see any change in colour or any fluid
- Check that your baby is moving as usual
- If tightenings start, time them with a contraction timer
- Carry on with your day; a bath or shower is fine while your waters are intact
- Do not use a tampon to catch it; it hides the colour you need to see
The NHS says to call your midwife or maternity unit once contractions come regularly every 5 minutes or more often, and to call urgently if any contraction lasts longer than 2 minutes or you have 6 or more in 10 minutes. Many units use the 5-1-1 rule for a first baby: contractions every 5 minutes, each lasting about a minute, for an hour. Follow your own unit's instructions where they differ.
Call your maternity unit straight away, at any hour, if: you see bright red blood, more than a streak, or clots; you are under 37 weeks; fluid is leaking, especially if it is green or brown; your baby is moving less than usual; you have a fever; or you have severe or constant tummy pain.
Call 999 in the UK or 911 in the US if the bleeding is heavy (soaking a pad soon after you put it on), or if you have severe pain, pain in your shoulder, or feel faint or dizzy.
At a Glance
The mucus plug is a jelly-like seal in the cervix that forms early in pregnancy and helps hold back bacteria. Near term it comes away, in one piece or several, clear or streaked pink or brown, and sometimes you never see it. After 37 weeks that is a normal sign that the cervix is changing, but it predicts labour badly: hours, days or weeks can follow. Contractions decide when you go in. Before 37 weeks, or with bright red bleeding, fluid or fewer movements, call.
Inside Baby Novum. When tightenings start after a show, the app's contraction timer logs each one with a tap, works out the averages and alerts you when the 5-1-1 pattern has lasted an hour. It records; your maternity unit decides.
Next: Signs of Labor: When to Go to the Hospital → · Water Breaking → · Hospital Bag Checklist →
Frequently Asked Questions
What does the mucus plug look like?
The mucus plug is a thick, jelly-like discharge that may be clear, pink or streaked with brown or red blood. Losing it (a 'show') can happen days or even weeks before labour begins, so it is a sign — not a starting gun.
Can the mucus plug be clear, with no blood at all?
Yes. The plug is often clear or off-white, and many women never see any blood in it. Pink, red or brown streaks come from small blood vessels in the cervix as it softens and opens. A plug without blood means the same thing as one with it: the cervix is changing. Neither version tells you labour will start today.
How long after losing the mucus plug does labour start?
Nobody can tell you from the plug alone. The NHS says labour may follow quickly or take a few days, and Cleveland Clinic notes that some women go on for a few weeks. Treat it as a sign that your cervix is getting ready, keep your phone charged, and let contractions, not the plug, decide when you leave.
Can the mucus plug come out in pieces, or grow back?
Both happen. The NHS describes it coming away in one blob or in several pieces, and some women lose small amounts of thick mucus over several days without noticing a single moment. The cervix also keeps producing mucus, so the plug can partly re-form and you may lose more later. Losing some of it once does not leave your baby unprotected.
Is it normal to lose mucus with blood after a membrane sweep or internal exam?
Yes, within limits. A sweep or vaginal examination disturbs the cervix, and the NHS lists cramping and some vaginal bleeding afterwards as expected. Blood-streaked mucus or light spotting over the next day is common. Bleeding that is bright red and flowing, that soaks a pad, or that comes with constant pain needs a call to your maternity unit straight away.
What if I lose my mucus plug at 30 weeks?
Call your maternity unit or midwife the same day. Before 37 weeks, a change in discharge, mucus or blood can be an early sign of preterm labour, and Cleveland Clinic advises contacting your provider whenever the plug comes away before 37 weeks. Most of these calls end in reassurance, but if it is preterm labour, treatment given early helps your baby.
Can I take a bath after losing my mucus plug?
If your waters are intact, yes. Cleveland Clinic says there is usually nothing you need to avoid after losing the plug, because the membranes around the baby are still closed. The rule changes once your waters break: from then on, showers only and no sex, because of the infection risk, and you should call your maternity unit.
Do I need to go to hospital when I lose my mucus plug?
Not at term, if the mucus is only streaked with blood and nothing else is happening. Mention it at your next appointment or when you call about contractions. Call straight away if you are under 37 weeks, if you see bright red bleeding beyond a streak, if fluid is leaking, or if your baby is moving less.
Sources
- NHS — Signs that labour has begun
- NHS — Vaginal bleeding in pregnancy
- NHS — Premature labour and birth
- NHS — Inducing labour
- Cleveland Clinic — Mucus Plug
- Cleveland Clinic — Bloody Show
- MedlinePlus — Am I in labor?
- Hansen LK et al. — The cervical mucus plug inhibits, but does not block, the passage of ascending bacteria (Acta Obstet Gynecol Scand, 2014)