Obstetric analgesia and anaesthesia

• Labour is intensely painful, and treating that pain is a normal part of care: the World Health Organization (WHO) and the American College of Obstetricians and Gynecologists (ACOG) both state that a woman's request alone is a sufficient indication for pain relief in labour, provided there is no medical contraindication. ^[3][4]
• Neuraxial techniques (epidural and, less commonly, spinal or combined spinal-epidural analgesia) are the most effective and flexible options; they do not increase the chance of caesarean birth, although they are associated with a longer second stage of labour and more instrumental births. ^[5][4]
• Systemic opioids provide useful but limited relief, nitrous oxide (usually a 50:50 mixture with oxygen) is safe and widely used but less effective than an epidural, and a pudendal nerve block targets the perineal pain of the second stage. ^[1][7][5]
• For caesarean birth, regional anaesthesia (spinal or epidural) is offered in preference to general anaesthesia; general anaesthesia is reserved for emergencies or when regional block is impossible or has failed. ^[2][5]
• Consent, timing, asepsis and vigilance (maternal blood pressure, fetal heart rate, respiratory monitoring after intrathecal opioids) matter as much as the technical steps. ^[1][2]

By the end of this page you should be able to:

1. Explain why labour hurts and which neural pathways carry first-stage and second-stage pain.
2. Choose among epidural, combined spinal-epidural, spinal, opioid, nitrous oxide and pudendal block for a given stage of labour, citing contraindications.
3. Describe the preparation, consent and step-by-step technique of the common obstetric blocks.
4. Recognise and manage hypotension, fetal bradycardia, failed block, post-dural puncture headache and other complications.
5. Outline guideline-based care after caesarean birth under regional and general anaesthesia, including neuraxial opioid dosing and respiratory monitoring.
6. Summarise what ACOG, NICE, WHO and RCOG each recommend about obstetric analgesia and anaesthesia.

Obstetric analgesia and anaesthesia covers the relief of labour pain and the anaesthesia used for caesarean and other operative deliveries. The subject has four layers that must be learned together: the pain pathways of labour, the drugs used, the anatomy and technique of each block, and the maternal-fetal monitoring that keeps both safe. This page follows the order a clinician needs: indications, contraindications, preparation and consent, steps, aftercare, complications, then the evidence and published guidelines, finishing with a decision flowchart. The guideline editions named throughout are NICE guideline NG235 (intrapartum care, pain relief section, published 2023), NICE guideline NG192 (caesarean birth, published 2021, last updated June 2025), the WHO recommendations on intrapartum care for a positive childbirth experience (2018), ACOG Practice Bulletin No. 209 (2019, reaffirmed 2024), and the Royal College of Obstetricians and Gynaecologists (RCOG) Green-top Guideline No. 45. ^{[1][2][3][4][9]}

It complements, but is not the same as, two other MedGrasp pages: regional and local anaesthesia (the pharmacology and dose ceilings of local anaesthetics, spinal needles and lipid emulsion) and general anaesthesia and airway management (induction agents, maintenance and the obstetric airway). Those pages should be read if you need drug mechanisms; this page is about obstetric application.

Labor pain. Labour causes severe pain for many women, and there is no other situation in which untreated severe pain that can be safely relieved would be acceptable while someone is under a doctor's care. ^[4] For this reason ACOG states that when nothing medical argues against it, the mother's own request is by itself enough of a reason for pain relief during labour, and that the methods available within an institution must not depend on a woman's ability to pay. ^[4] NICE recommends that Entonox (a 50:50 mixture of oxygen and nitrous oxide) be available in all birth settings, that pethidine, diamorphine or other opioids be available in all birth settings, and that women be informed what each option offers. ^[1] WHO recommends epidural analgesia and parenteral opioids such as fentanyl, diamorphine and pethidine as options for healthy pregnant women requesting pain relief, depending on their preferences, alongside relaxation and manual techniques. ^{[3] [2]}

Caesarean birth. For caesarean birth, NICE says regional anaesthesia should be offered in preference to general anaesthesia, including for women with placenta praevia. ^[2] General anaesthesia is used for emergency caesarean birth when neuraxial anaesthesia is not available or cannot be given quickly enough. ^[5]

Other obstetric procedures. Repairs of severe perineal tears, complicated lacerations, manual removal of the placenta, instrumental vaginal birth (forceps or vacuum), and procedures such as external cephalic version in a distressed or anxious patient may need an epidural top-up, a spinal (saddle) block or a pudendal block. ^[5]

Early and individualised timing. Unlike older teaching, waiting for a particular cervical dilatation is unnecessary: Spanish and German guidelines, the American Society of Anesthesiologists and ACOG all support starting low-dose neuraxial analgesia early in labour, and the evidence does not show that doing so increases caesarean birth rates. ^[6] NICE similarly advises that remifentanil patient-controlled analgesia (PCA) and epidural care must be explained, offered and documented with the woman. ^[1]

Neuraxial blocks (epidural, spinal, combined spinal-epidural). The usual contraindications are infection at the proposed insertion site, therapeutic anticoagulation or a significant coagulation disorder, a severe bleeding tendency and suspected raised intracranial pressure. Relative situations (aortic stenosis, certain neurological disease, recent lumbar surgery, gross obesity) are case-by-case decisions for an obstetric anaesthetist. Anticoagulation and neuraxial blockade are a specialist shared decision; follow the current anticoagulant guidance for regional techniques rather than memory. ^[5]

Remifentanil PCA. NICE restricts this to obstetric units because of the risk of maternal respiratory depression that may need anaesthetic support. ^[1]

Paracervical block. This is rarely appropriate because the incidence of fetal bradycardia exceeds 10 percent. ^[5]

Parenteral opioids. NICE and Merck both warn that opioids cross the placenta and can cause neonatal respiratory depression and drowsiness, so the smallest effective dose is used. ^[1][5] Codeine-containing analgesics should be avoided in breastfeeding women because of the risk of serious neonatal sedation and respiratory depression. ^[2][5]

Nitrous oxide. Nitrous oxide (usually the 50:50 mixture) is contraindicated or relatively contraindicated in women with closed air-space disease (for example, severe asthma attack, pneumothorax, bowel obstruction) and in undiagnosed acute abdomen, and should be avoided when oxygen delivery is already compromised. Mask anxiety, nausea and practical exhaustion limit its use even when it is safe. The debate about its metabolic, folate and neurodevelopmental effects is unresolved; counsel accordingly, and recognise the competing positions below. ^[7]

General anaesthesia. The aspiration risk of a full stomach in late pregnancy is the main hazard; hence the left lateral tilt, antacids, rapid sequence induction, pre-oxygenation and cricoid pressure described below. ^[2]

Pain pathways. In the first stage of labour, visceral afferents from the cervix and lower uterine segment enter the spinal cord at T10 to L1, so pain is felt in those dermatomes (lower back, abdomen, thighs). ^[6] In the second stage, somatic fibres from the vagina, perineum and pelvic floor travel in the pudendal nerve to S2 to S4, producing the sharp perineal pain of descent and crowning. ^[6] Epidural analgesia can block visceral, somatic or both components depending on the levels covered.

The pudendal nerve. It leaves the pelvis through the greater sciatic foramen, hooks around the ischial spine, and re-enters via the lesser sciatic foramen to run in Alcock's canal. A local anaesthetic injected transvaginally or transperineally where the nerve crosses the ischial spine bathes the distal nerve. ^[5]

Cardiovascular physiology. Aortocaval compression in the supine position, plus the sympathetic block produced by neuraxial anaesthesia, can drop blood pressure and reduce utero-placental flow. ^[6] Left lateral tilt and vasopressors (phenylephrine first-line, with ephedrine boluses for bradycardia) are the countermeasures. ^[2][6]

Talk about pain relief early. NICE recommends discussing preferences in pregnancy, and offering information on all methods, including when transfer to an obstetric unit would be needed. ^[1] ACOG adds that the choice of methods should be explained, that a woman who requests epidural analgesia should not be deprived of it because of insurance status, and that anaesthesia services should be available in every hospital that offers maternal care (levels I to IV). ^[4]

Consent for caesarean birth. RCOG's consent advice on planned caesarean birth is built on the same balanced-discussion principle, and should be used together with patient information leaflets. ^[9]

Consent for neuraxial care. NICE says that if a woman requests regional analgesia, talk about the benefits, risks and effect on labour, and then support her decision: more effective pain relief than opioids; not always fully effective; complications during insertion (including severe postnatal headache); no long-term backache; no increase in first-stage length or unplanned caesarean; longer second stage and more instrumental births; and reduced mobility because of closer monitoring and intravenous access. ^[1]

Intravenous access. NICE: always secure intravenous access before starting regional analgesia. ^[1] Preloading or maintenance fluids do not need to be given routinely before low-dose epidural or combined spinal-epidural analgesia. ^[1]

Screening and laboratory tests. According to the review by Heesen and Veeser, no routine laboratory tests are needed before regional anaesthesia in a woman with an unremarkable history and no haemorrhage; measure the platelet count if there is pre-eclampsia, and do thorough coagulation testing if values are abnormal, there has been pathological bleeding or HELLP syndrome is suspected. ^[6] The same review notes that a platelet count between 80,000 and 100,000 per microlitre is not unusual in healthy pregnancy and rises peripartum; no absolute cut-off for neuraxial puncture has been established, and the acute change in the count with the anaesthetist's risk-benefit assessment matters more than a single number. ^[6]

Antacid prophylaxis for caesarean birth. NICE offers women antacids and H2-receptor antagonists or proton pump inhibitors (the latter off-label in March 2021) before caesarean birth to reduce gastric volume and acidity, and says each unit should have a failed-intubation protocol. ^[2]

Fasting and gastric volume. NICE notes that eating a low-residue diet in labour increases gastric volume without a proven effect on aspiration risk, and that isotonic drinks during labour do not increase gastric volume. ^[2] This is honest uncertainty that should be discussed before general anaesthesia rather than hidden.

The sequence below is the logical order regardless of the method eventually chosen.

1. Assess the stage of labour, pain, maternal condition, fetal heart rate and any contraindications; discuss options and document.
2. Place the woman in a safe position, secure monitoring, establish intravenous access.
3. For an epidural or combined spinal-epidural during labour, perform the block in the sitting or lateral position with full asepsis; give a test dose; assess motor and sensory levels.
4. Start analgesia, reassess in 15 to 30 minutes, set up patient-controlled epidural analgesia or a continuous infusion.
5. Maintain monitoring (blood pressure, fetal heart, block height, motor power) and top-up or shorten the block for delivery or surgery.
6. For an operative delivery without epidural in place, choose spinal (faster, smaller dose) or, in some situations, general anaesthesia; for caesarean birth, left lateral tilt, phenylephrine and warming of fluids follow.

Establishing labour analgesia. NICE: use either epidural or combined spinal-epidural (CSE) analgesia to establish regional analgesia; if rapid analgesia is needed, use CSE. ^[1] Establish CSE with bupivacaine (or an equivalent local anaesthetic) and fentanyl, and establish epidural analgesia with a low-concentration local anaesthetic plus fentanyl solution, giving the first dose cautiously as a test dose to rule out inadvertent intrathecal or intravascular placement. ^[1] Heesen and Veeser add that in CSE the epidural space is first identified with the epidural needle, an introducer is used for the spinal needle, the intrathecal injection is given, and then the epidural catheter is threaded; the intrathecal opioid works in 2 to 5 minutes versus 15 to 20 minutes for an epidural alone. ^[6] After intrathecal opioid without local anaesthetic, the woman can still walk because there is no motor block. ^[6]

Ongoing maintenance. NICE: blood pressure every 5 minutes for 15 minutes during establishment or after boluses of 10 ml or more; ask the anaesthetist to review if she is not pain-free 30 minutes after each dose; assess sensory block hourly; if she is not mobilising, assess motor block hourly with a straight leg raise, asking the anaesthetist to review if she cannot do this. ^[1] Perform continuous cardiotocography for at least 30 minutes during establishment and after each bolus of 10 ml or more. ^[1] Once established, continue regional analgesia until after the third stage and any perineal repair. ^[1]

Pudendal nerve block. Merck describes the technique as injecting a local anaesthetic through the vaginal wall so that it bathes the pudendal nerve as it crosses the ischial spine; this anaesthetises the lower vagina, perineum and posterior vulva, but not the anterior vulva (innervated by lumbar dermatomes). ^[5] It is a safe, simple method for uncomplicated spontaneous vaginal deliveries when a woman does not want neuraxial analgesia, or when labour is so advanced that there is no time for an epidural, and it is used for operative vaginal birth and repair of complex lacerations. ^[5] Complications are intravascular injection, haematoma and infection. ^[5] Heesen and Veeser describe paracervical (Frankenhauser ganglion) block as a way to abolish first-stage visceral pain without motor block, but its complications include fetal bradycardia and inadvertent fetal injection with systemic local anaesthetic toxicity; Merck gives a fetal bradycardia incidence above 10 percent. ^[5][6]

Parenteral opioids. NICE insists on an antiemetic with any intravenous or intramuscular opioid, and warns that women must not enter water within 2 hours of opioid administration or if drowsy. ^[1] Merck lists commonly used regimens (fentanyl 100 micrograms, or morphine sulfate up to 10 mg intravenously every 60 to 90 minutes, with the minimum amount needed for comfort) and warns that if toxicity occurs, respiration should be supported and naloxone 0.01 mg per kg given by intramuscular, intravenous, subcutaneous or endotracheal route, repeated in 1 to 2 minutes as needed. ^[5] For remifentanil PCA, NICE proposes 40 micrograms per bolus with a 2-minute lockout in an obstetric unit, with a midwife trained in its use continuously present, cardiotocography, and continuous respiratory monitoring with supplemental oxygen and immediate anaesthetic support available; this was an off-label use at the time of review. ^[1] Heesen and Veeser report that bolus doses in practice range from 0.25 to 0.7 micrograms per kg with a lockout of 1 to 5 minutes, and that pain reduction is good in the first hour but pain can return in the second hour. ^[6]

Nitrous oxide. NICE simply requires Entonox in all birth settings and warns about nausea and light-headedness. ^[1] In a 50:50 oxygen-and-nitrous mixture it is self-administered by demand valve, producing anxiolysis and mild analgesia; onset within about 1 minute; pain scores fall only modestly (about 0.5 points on a visual analogue scale versus about 1.5 for remifentanil and about 5 for epidural analgesia), but many women report similar satisfaction to epidural users and would choose it again. ^[7][6] Adverse effects include drowsiness, nausea, vomiting, dizziness and, with unscavenged systems, possible occupational exposure. ^[7] NICE's cautious phrasing and the broader literature (in which only two nitrous-oxide studies for labour met good-quality criteria) justify presenting it honestly as a useful, safe but relatively weak option. ^[7] Merck notes that nitrous oxide 40 percent with oxygen is occasionally used for vaginal delivery while verbal contact is maintained. ^[5]

Neuraxial caesarean anaesthesia. NICE: regional anaesthesia in preference to general, including with placenta praevia; induction (including regional) in theatre; left lateral tilt up to 15 degrees; prophylactic phenylephrine infusion after spinal injection with maternal blood pressure kept at 90 percent or more of baseline and not allowed to fall below 80 percent; ephedrine boluses if the heart rate is low; intravenous crystalloid co-loading in addition to vasopressors; warmed intravenous fluids and irrigation; anti-emetics; antacids. ^[2] Merck adds that vital signs should be checked every 5 minutes when a spinal has been used, because hypotension is the predictable problem. ^[5]

General anaesthesia for caesarean birth. NICE: every maternity unit must have procedures for failed intubation; pre-oxygenation, cricoid pressure and rapid sequence induction are used to reduce aspiration; a practitioner skilled in neonatal resuscitation must be present; after general anaesthesia a professional with airway skills performs continuous one-to-one observation until airway control, haemodynamic stability and the ability to communicate have all returned, then half-hourly observations for 2 hours. ^[2] General anaesthesia is reserved for emergencies or when regional block is impossible. ^[5]

After caesarean under regional anaesthesia. NICE requires continuous one-to-one observation until haemodynamic stability (return of pulse and blood pressure to baseline). ^[2] After intrathecal or epidural diamorphine, hourly monitoring of oxygen saturation, respiratory rate and sedation for at least 12 hours applies if risk factors for respiratory depression are present; after morphine, the risk of respiratory depression is greater and more prolonged, so the same 12-hour hourly monitoring is used with risk factors, and extra monitoring is considered in others. ^[2] Urinary catheter removal should wait until the woman is mobile after a regional anaesthetic, and not sooner than 12 hours after the last top-up. ^[2]

Post-caesarean analgesia. NICE recommends intrathecal diamorphine up to 300 micrograms (epidural up to 3 mg) as the first choice; if diamorphine is unavailable, intrathecal preservative-free morphine up to 100 micrograms plus fentanyl up to 15 micrograms intrathecally, or epidural preservative-free morphine up to 3 mg. ^[2] Morphine given neuraxially increases nausea, vomiting and itching compared with diamorphine and may need treatment, and must be preservative-free with clear storage separation. ^[2] Otherwise: paracetamol and (unless contraindicated) an NSAID in combination, regularly rather than as needed; oral immediate-release morphine sulfate (or intravenous, intramuscular or subcutaneous morphine if oral medication is not tolerated) for women who received spinal or epidural anaesthesia; intravenous PCA morphine (or oral morphine) after general anaesthesia; dihydrocodeine, tramadol or low-dose oxycodone only for severe breakthrough pain; codeine avoided in breastfeeding. ^[2] Laxatives and anti-emetics are considered, and women discharged on opioids are told to seek help if the baby shows drowsiness, breathing difficulty, constipation or feeding difficulty. ^[2] ACOG's stepwise multimodal approach (NSAIDs, paracetamol, low-potency opioids) is the matching consensus. ^[5]

After caesarean under general anaesthesia. As summarised above, one-to-one observation until airway control, haemodynamic stability and communication return, then half-hourly observations for 2 hours, then routine postnatal checks. ^[2]

Hypotension. The predictable hazard of spinal or epidural anaesthesia in pregnancy; treated with left tilt, intravenous fluids and vasopressors, monitored with blood pressure checks every 5 minutes at first. ^[2][5]

High or total spinal block. A block climbing to the cervical or intracranial level can paralyse respiration and produce cardiovascular collapse. Recognition: rapidly rising sensory level, arm weakness, dyspnoea or drowsiness; management is airway protection, ventilation, oxygen, vasopressors and fluids. ^[5]

Fetal bradycardia after intrathecal opioids. Mardirosoff's meta-analysis found fetal bradycardia more common after intrathecal opioids; it can occur independently of maternal hypotension during the first 15 to 45 minutes after epidural or combined spinal-epidural. ^[6]

Maternal hyperthermia. Epidural analgesia extending beyond 6 hours has been associated with maternal temperature rise in 1 to 46 percent of women; the mechanism is uncertain, and neonates in these cases are more likely to be investigated and treated for sepsis. ^[6]

Urinary retention. More common with epidural analgesia; sacral blockade impairs bladder emptying and explains the 12-hour catheter rule above. ^[6][2]

Post-dural puncture headache (PDPH). Accidental dural puncture during epidural catheter placement occurs in an estimated 0.5 to 1.5 percent of women in labour. ^[8] PDPH then develops in roughly 50 to 80 percent of them, usually within the first five days. ^[8] It is a dull, throbbing frontal or occipital headache that worsens on sitting or standing and improves lying flat; neck stiffness (10 to 25 percent), nausea and vomiting (20 percent), tinnitus (10 percent), photophobia (23 percent), diplopia (2 percent) and, rarely, cranial nerve palsies can accompany it. ^[8] Cerebrospinal fluid hypotension explains it. Management follows the multisociety consensus: no routine bed rest (upright restriction only for temporary relief), multimodal analgesia, oral fluids with intravenous fluids if needed, caffeine (up to 300 mg per day if breastfeeding, up to 900 mg if not) in the first 24 hours, and an epidural blood patch when conservative measures fail, with a reported success rate of 33 to 91 percent; about 15 percent of patients need a second patch. ^[8] Severe or atypical headaches may have other causes (cerebral venous sinus thrombosis, haemorrhage, infection) and need urgent imaging. ^{[8] [6]}

Epidural haematoma and infection. Rare but catastrophic; the reason neuraxial techniques must obey anticoagulant guidance. The SBA's regional safety guidance, drawing on the Third National Audit Project, estimated major infectious complications of neuraxial anaesthesia at about 1 in 40,000, higher after epidural than spinal. ^[5]

Failed or inadequate block. Neuraxial analgesia fails in an estimated 12 percent of cases, most of which can be improved with repositioning or catheter manipulation; do not chase failure with repeated large doses without recounting total local anaesthetic. ^[6]

Nitrous-associated effects. Sedation, nausea and vomiting; with unscavenged systems, occupational exposure risk to staff. ^[7]

Parenteral-opioid neonatal effects. Dose-dependent respiratory depression and drowsiness that may last days and make breastfeeding harder; treat with naloxone as above. ^[1][5]

Pudendal-block complications. Intravascular injection, haematoma and infection; the anterior vulva is not anaesthetised by this block. ^[5]

WHO (2018, intrapartum care for a positive childbirth experience, recommendations 19 and 20). Epidural analgesia and parenteral opioids such as fentanyl, diamorphine and pethidine are recommended for healthy pregnant women requesting pain relief, depending on preference; pain relief should not be used to prevent or shorten delay in labour. ^[3]

ACOG (Practice Bulletin No. 209, 2019, reaffirmed 2024). Labour causes severe pain for many women; in the absence of medical contraindication, maternal request is a sufficient indication, and no institution should make methods of labour analgesia dependent on a patient's ability to pay; anaesthesia services should be available in all hospitals offering maternal care (levels I to IV). ^[4]

NICE (NG235, intrapartum care, pain relief in labour, and NG192, caesarean birth, anaesthesia and postnatal care, published and updated through 2025). Key points used above: availability of Entonox, opioids, remifentanil PCA, combined spinal-epidural with bupivacaine and fentanyl, observations and top-ups, regional anaesthesia preferred for caesarean birth, phenylephrine thresholds 90 and 80 percent, left tilt, intrathecal diamorphine dosing up to 300 micrograms, morphine 100 micrograms plus fentanyl 15 micrograms, 12-hour postoperative monitoring after neuraxial morphine or diamorphine with risk factors, and avoidance of codeine in breastfeeding. ^[1][2]

RCOG (Birth after Previous Caesarean Birth, Green-top Guideline No. 45). There is a broad consensus (NICE, RCOG, ACOG) that planned vaginal birth is clinically safe for most women with a single previous lower-segment caesarean delivery, so neuraxial analgesia should be offered and not withheld on the basis of a previous caesarean birth. ^[9]

Points on which sources differ. Merck's professional summary reserves general anaesthesia for emergency caesarean delivery, while NICE's caesarean guideline details pre-oxygenation, cricoid pressure and rapid sequence induction when general is used. ^[2][5] On concentrations, NICE's Entonox is a 50:50 mixture, whereas some services (for example, those following Merck's description) use 40 percent nitrous oxide with oxygen. ^[1][5] On injection, Merck gives a paracervical fetal bradycardia incidence above 10 percent, making the technique an uncommon choice. ^[5] On nitrous oxide overall, the review by Vallejo and Zakowski presents both sides: one author argues it is safe, cheap and popular, the other argues for limitation because of metabolic and potential neurodevelopmental effects disputed by the pro side; counsel women accordingly. ^[7] On pencil-point needles, spinal puncture with cutting needles carries a higher risk of post-dural puncture headache than pencil-point needles; this is the standard preventive strategy. ^[8]

• Labour pain is a physiological, not a social, problem; relieving it is part of normal obstetric care, and many bodies regard maternal request alone as sufficient indication. ^[4]
• Neuraxial analgesia is the most effective option, with onset in minutes for epidural and 2 to 5 minutes for combined spinal-epidural; it does not increase caesarean rates but prolongs the second stage and increases instrumental delivery. ^{[6] [5]}
• Start low-dose neuraxial analgesia when the woman asks for it; do not insist on an arbitrary cervical dilatation. ^[6]
• Entonox (50:50) must be available in all birth settings; it helps some women and is safe, but it is substantially less effective than epidural analgesia. ^[1][7]
• Systemic opioids are second-line, need an antiemetic and careful neonatal observation; remifentanil PCA is effective in the first hour and is restricted to obstetric units. ^[1][6]
• Pudendal block targets S2 to S4 perineal pain; it does not cover the anterior vulva and is not useful for first-stage pain. ^[5]
• For caesarean birth, regional anaesthesia is preferred to general anaesthesia; general anaesthesia requires rapid sequence induction, left tilt and strict postoperative observation. ^[2][5]
• Phenylephrine is the favoured vasopressor under spinal anaesthesia for caesarean birth; aim to keep maternal blood pressure at 90 percent or more of baseline and avoid falls below 80 percent. ^[2][6]
• Accidental dural puncture occurs in an estimated 0.5 to 1.5 percent of labour epidurals and causes post-dural puncture headache in roughly half of those affected; manage with conservative measures and, if needed, an epidural blood patch. ^[8]
• Intrathecal and epidural opioids have specific doses, preparations and monitoring requirements; neuraxial morphine in particular needs at least 12 hours of respiratory monitoring when risk factors exist. ^[2]
• A fourth-degree tear or other operative perineal repair can usually be managed with spinal or epidural anaesthesia, with general anaesthesia reserved for unusual situations. ^[9]
• Guidelines agree on availability and maternal choice, but differ on detail: the nitrous oxide concentration offered, the place of paracervical block, and the limits of nitrous oxide use. ^[1][5][7]

• Regional and local anaesthesia
• General anaesthesia and airway management
• Perioperative care
• Postoperative pain and analgesia
• Neonatal resuscitation
• Hypotension and shock in pregnancy