Epidural: how it works and what it really changes
Updated October 13, 2026 · sources checked October 13, 2026
In short
An epidural is a local anaesthetic, often mixed with an opioid, given through a thin tube in your lower back by an anaesthetist. It takes about 10 minutes to set up and 10 to 20 minutes to work, and usually gives very good pain relief. NICE says it does not raise the chance of an unplanned caesarean or cause long-term backache, but can lengthen the pushing stage.
What an epidural is
An epidural is a form of regional pain relief. Medicine, usually a mixture of local anaesthetic and opioid, flows through a very thin tube placed near the nerves that carry pain signals from your womb. ACOG notes it is the most common pain relief used for childbirth in the United States. You stay awake and alert, and you should still be able to push.
Only an anaesthetist (anesthesiologist in the US) can give an epidural, so it is not available at home, and NICE notes it is only available in obstetric units. If you think you might want one, check that anaesthetists are always available where you plan to give birth.
How it is placed, step by step
- A drip goes into a vein in your arm.
- You sit curled forward or lie on your side with your back rounded.
- The anaesthetist cleans your back and numbs a small area with local anaesthetic.
- A needle is placed in your lower back, a thin tube is passed through it, and the needle is removed. The tube stays.
- Medicine runs through the tube. Setting up takes about 10 minutes, and it takes another 10 to 15 minutes to work (NHS).
- It can be topped up by your midwife, or by you with a pump.
- Your contractions and your baby's heart rate are then monitored continuously.
Side effects, with the figures
| Effect | How common, or how it is handled | Source |
|---|---|---|
| Heavy legs | Depends on the anaesthetic used | NHS |
| Drop in blood pressure | Rare: the drip helps prevent it | NHS |
| Difficulty peeing | A small catheter may be used | NHS, ACOG |
| Itching | Common when opioids are used; can be treated | ACOG |
| Headache | About 1 in 100, and treatable | NHS |
| Pins and needles in one leg after birth | About 1 in 2,000, more often due to the birth itself | NHS |
| Shivering, cold sore reactivation | Possible | ACOG |
| Sore back | For a day or two; no long-term backache | NHS, NICE |
| Not fully effective | May need adjusting or replacing | NICE |
What the evidence says it changes, and what it does not
NICE asks midwives to give every woman who requests an epidural this information:
- it gives more effective pain relief than opioids
- it is not associated with a longer first stage of labor or a higher chance of an unplanned caesarean
- it is associated with a longer second (pushing) stage and a higher chance of birth with forceps or vacuum
- it comes with more monitoring and a drip, so you may move less
- it is not associated with long-term backache
The largest review, a Cochrane analysis using data from 40 trials and more than 11,000 women, found epidurals were more effective for pain and increased satisfaction with pain relief. The rise in assisted births was not seen in studies published after 2005, suggesting modern approaches may not affect it. Epidurals had no impact on caesarean risk, long-term backache or babies' Apgar scores (Anim-Somuah et al., 2018).
With an epidural, NICE notes that once you are fully dilated, pushing may be delayed by 1 hour if you have given birth before, or up to 2 hours for a first baby, unless you feel the urge or your baby's head is visible.
Spinal and combined spinal-epidural
- Spinal block: a single injection with a much thinner needle. It works quickly but lasts only an hour or two, which is why it is commonly used for a caesarean (ACOG).
- Combined spinal-epidural (CSE): a spinal for immediate relief, then an epidural tube for continuous relief, with lower doses than an epidural alone for the same relief (ACOG).
Is this normal? When to call
Heavy legs, itching, shivering and a sore back for a day or two are normal after an epidural. Tell your midwife or doctor if you have a headache after the birth: NICE notes that complications at insertion can cause a severe postnatal headache, and the NHS says it can be treated.
Back home, call your midwife, OB-GYN or GP if a severe headache, numbness or weakness does not settle. In the UK call NHS 111 if you cannot reach them; for anything sudden and severe call 911 (US) or 999 (UK).
When it may not be suitable
ACOG lists heart disease, certain blood disorders, liver disease and previous spinal surgery among conditions that may affect your options. If one applies to you, ask to meet the anaesthetic team before labor.
Questions to ask before labor
- Is an anaesthetist available 24 hours a day where I am giving birth?
- Do you offer mobile epidurals?
- Can I top it up myself?
- What positions can I use once it is in? NICE recommends any position you find comfortable except lying flat on your back; see labor positions.
Choosing an epidural is a choice, not a failure, and so is choosing not to. You do not have to decide in advance. ACOG is clear that you can ask for pain relief during labor, that you can change your mind, and that using pain medication does not make your birth "less natural". Note your current thinking in your birth plan.
Questions parents ask
How long does an epidural take to work?
The NHS says it takes about 10 minutes to set up and another 10 to 15 minutes to work; ACOG says pain relief should begin within 10 to 20 minutes after the medicine starts.
Does an epidural increase the risk of a C-section?
No. NICE states it is not associated with an increased chance of an unplanned caesarean, and a Cochrane review of 40 trials found no impact on caesarean risk. It is linked with a longer pushing stage and more assisted births with forceps or vacuum.
Can I walk with an epidural?
Sometimes. Some hospitals offer "mobile" epidurals, but these need remote monitoring of the baby's heart rate, which many hospitals do not have. Ask your unit what they offer.
Does an epidural cause long-term back pain?
No. The NHS and NICE both say it does not cause long-term backache, although your back may be a little sore for a day or two.
Does an epidural affect my baby?
ACOG describes the overall risks for the baby as low; when opioids are part of the mix, short-term effects on heart rate, breathing, drowsiness and early breastfeeding are possible.
Sources
- NHS — Pain relief in labour (epidural section) checked October 13, 2026
- ACOG — Medications for Pain Relief During Labor and Delivery (FAQ) checked October 13, 2026
- NICE NG235 — Intrapartum care, information about regional analgesia checked October 13, 2026
- Anim-Somuah M et al. Epidural versus non-epidural or no analgesia for pain management in labour. Cochrane Database Syst Rev 2018 (PMID 29781504, DOI 10.1002/14651858.CD000331.pub4) checked October 13, 2026
Mamavela explains; it does not replace your midwife, doctor or pediatrician, who know your situation. If something worries you, call them. In an emergency, call 911 (US), 999 (UK) or 112.