Clinical overview
Preterm birth — delivery before 37 completed weeks (259 days) of gestation — is the single largest direct cause of neonatal death and long-term neurodevelopmental disability worldwide, and a dominant driver of perinatal mortality in South Africa. The registrar's task is rarely glamorous: it is the unglamorous, high-leverage work of buying gestational weeks, protecting the brain and lungs, and getting the baby born in the right place. Two related but distinct clinical problems dominate this objective. The first is preterm labour with intact membranes — regular contractions with cervical change before term. The second is preterm prelabour rupture of membranes (PPROM) — rupture of the fetal membranes before 37 weeks and before the onset of labour, which precedes roughly a third of preterm births and shifts the whole calculus towards infection.
The central tension in both is the same: every additional day in utero improves survival and reduces morbidity, but the intrauterine environment may itself become dangerous (chorioamnionitis, abruption, cord compression). Management is therefore a continuous risk–benefit negotiation between prolonging the pregnancy and delivering the baby — and in the South African setting, that negotiation is profoundly shaped by where the woman is. A 28-week delivery at a tertiary centre with a NICU and surfactant is a survivable event; the same delivery in a district hospital without ventilation or a neonatal team is frequently not. Decisions about tocolysis, transfer, and resuscitation cannot be separated from the level of care. The NDoH National Integrated Maternal and Perinatal Care Guideline (NDoH, 2024) frames this explicitly, and Saving Mothers/Saving Babies (NCCEMD) repeatedly identifies failure to refer in utero and failure to give antenatal steroids as avoidable contributors to preterm perinatal death.
Core knowledge
Definitions and gestational thresholds
- Preterm birth: delivery from viability up to 36⁺⁶ weeks. Subcategories matter clinically: extremely preterm (<28 weeks), very preterm (28 to 31⁺⁶), moderate (32 to 33⁺⁶), and late preterm (34 to 36⁺⁶). The bulk of births are late preterm, but the bulk of mortality and morbidity sits below 32 weeks.
- Threshold of viability: a moving line set by neonatal capability. South African resource realities mean the locally agreed threshold (commonly framed around ~26 weeks or a birth weight ~750–800 g in many public units, lower in well-resourced centres) is not identical to high-income thresholds. The 5th-edition NDoH guideline and local neonatal protocols define the institution's viability cut-off; the registrar must know the local one, because it determines whether active intervention (steroids, tocolysis, caesarean for fetal indication) is offered at all.
- PPROM: rupture of membranes before labour and before 37 weeks. Pre-viable PPROM (before the local viability threshold, classically <24 weeks) carries an additional burden of pulmonary hypoplasia and limb contractures from prolonged oligohydramnios and warrants honest, individualised counselling.
Why babies are born too early
Preterm birth is a syndrome, not a single disease, with overlapping pathways: intrauterine infection/inflammation (the dominant mechanism in early PPROM and very preterm labour — ascending genital tract organisms trigger prostaglandin-driven membrane weakening and myometrial activation); uteroplacental ischaemia/abruption; uterine overdistension (multiple pregnancy, polyhydramnios); cervical insufficiency; decidual senescence; and iatrogenic/indicated preterm birth for maternal or fetal disease (pre-eclampsia, growth restriction). Recognising the pathway reframes management — see multiple-pregnancy, intrauterine-growth-restriction and antepartum-haemorrhage.
Membrane physiology in PPROM
The membranes maintain the sterile amniotic compartment. Once ruptured, the latency period (rupture-to-delivery interval) is inversely related to gestation — earlier PPROM tends to have longer latency, but every day of latency raises the cumulative risk of chorioamnionitis, cord prolapse (especially with malpresentation or high presenting part), placental abruption, and fetal/neonatal sepsis. Oligohydramnios from ongoing loss adds cord compression and, if prolonged from early gestation, pulmonary hypoplasia.
Figure J18.1 — PPROM and preterm-birth mechanism map showing the shared inflammation-to-contractions pathway, latency trade-off, speculum-first diagnosis and the local-viability/NICU check.
Assessment
Preterm labour — is it real labour?
Most women presenting with threatened preterm labour will not deliver imminently, and over-treatment carries its own harms (unnecessary transfer, tocolytic side-effects, iatrogenic delivery). The assessment seeks to separate true preterm labour from a false alarm.
- History: gestation (re-confirm dating — see gestational-age-assessment), contraction frequency and painfulness, any fluid loss or bleeding (which changes everything — see antepartum-haemorrhage), fever, dysuria, decreased fetal movements (decreased-fetal-movements), and risk factors (previous preterm birth, multiple pregnancy, infection, smoking, short interpregnancy interval).
- Examination: maternal temperature, pulse, BP; abdominal palpation for tenderness (abruption), presentation, and contraction frequency; sterile speculum examination to look for cervical dilatation, visible membranes, pooling of liquor, and to take swabs. Avoid digital vaginal examination if PPROM is suspected — it introduces organisms, shortens latency, and adds nothing the speculum did not.
- Cervical assessment: cervical length on transvaginal ultrasound and, where available, fetal fibronectin help triage — a short cervix or positive fibronectin raises the probability of imminent delivery, while a long closed cervix and negative test reassure. These tools rule out better than they rule in; in many SA public units they are unavailable and clinical judgement plus serial assessment governs.
Confirming PPROM
- Sterile speculum is the cornerstone: direct visualisation of liquor pooling in the posterior fornix or trickling through the os is diagnostic.
- Where the diagnosis is uncertain, ancillary tests (nitrazine/pH, ferning, or commercial placental-microglobulin/IGFBP-1 assays) may help, but a clear pooling sign needs no test.
- Ultrasound for amniotic fluid volume, presentation, fetal wellbeing and estimated weight supports the picture but a normal liquor volume does not exclude PPROM.
- Actively look for infection: maternal temperature, pulse, uterine tenderness, offensive discharge, fetal tachycardia, maternal white cell count and CRP (trend more useful than a single value), and a high vaginal swab. Chorioamnionitis is a clinical diagnosis supported by these features, not a laboratory one.
Don't forget the basics
Confirm HIV status and ART (untreated HIV and other genital infections are associated with preterm birth and PPROM — see hiv-in-pregnancy); screen for and treat asymptomatic bacteriuria and symptomatic UTI; and consider infections-in-pregnancy broadly. Group B streptococcus status guides intrapartum antibiotic prophylaxis.
Management
The four interventions that change outcomes in threatened or actual preterm birth are, in order of impact: antenatal corticosteroids, in-utero transfer to the right level of care, magnesium sulphate for neuroprotection, and selective, time-limited tocolysis to enable the first three. Antibiotics are central in PPROM. Tocolysis itself does not improve neonatal outcomes — its only job is to create a window for steroids and transfer.
Antenatal corticosteroids — the highest-yield intervention
- A single course of antenatal corticosteroids reduces neonatal death, respiratory distress syndrome, intraventricular haemorrhage and necrotising enterocolitis, and is recommended for women at risk of preterm birth across the relevant gestational range (RCOG GTG 74; NDoH 2024).
- Regimen (SA EML / NDoH): standard teaching is betamethasone 12 mg IM, two doses 24 hours apart, or dexamethasone 6 mg IM, four doses 12-hourly — dexamethasone is the widely available EML agent in South African public hospitals. Confirm the exact dose against the current EML/NDoH guideline at your facility.
- The greatest benefit accrues when delivery occurs more than 24 hours and up to 7 days after the first dose, but give the first dose even when delivery seems imminent — partial courses still help. Do not delay urgent delivery (e.g. for severe abruption or sepsis) to complete a course.
- Caution: steroids are not free. Avoid giving them "just in case" to women very unlikely to deliver preterm; weigh repeat courses carefully; and in diabetes anticipate hyperglycaemia and intensify glucose monitoring. Where overt maternal infection/chorioamnionitis mandates delivery, the imperative is to deliver, not to withhold a single steroid dose, but management is individualised.
Magnesium sulphate for fetal neuroprotection
- Magnesium sulphate given to women at imminent risk of very preterm birth reduces cerebral palsy and gross motor dysfunction in survivors. It is recommended for fetal neuroprotection at early gestations (commonly applied below ~30–32 weeks; follow the local NDoH/unit threshold).
- This is a distinct indication from eclampsia prophylaxis — same drug, different purpose. Use your unit's neuroprotection regimen (a loading dose followed by maintenance), monitor for magnesium toxicity (loss of patellar reflexes, respiratory depression, reduced urine output), and have calcium gluconate available as the antidote.
Tocolysis — buy time, nothing more
- Goal: delay delivery for ≤48 hours to allow steroids to act and to enable in-utero transfer. Tocolysis beyond this window is not justified.
- Agents: nifedipine (oral calcium-channel blocker) is a commonly used first-line agent; the oxytocin-receptor antagonist atosiban is an alternative where available. Beta-agonists are largely abandoned because of maternal cardiovascular side-effects. Use the agent and regimen specified by your local NDoH/EML guideline.
- Do NOT tocolyse when prolonging the pregnancy is dangerous: chorioamnionitis or maternal sepsis, significant antepartum haemorrhage/abruption, non-reassuring fetal status, lethal fetal anomaly, advanced cervical dilatation where delivery is inevitable, or any maternal condition (e.g. severe pre-eclampsia) requiring delivery. In these settings the membranes and contractions are telling you the baby is safer out.
Managing PPROM specifically
- Antibiotics prolong latency and reduce neonatal morbidity in PPROM and are recommended (RCOG GTG 73). The classic evidence base (ORACLE I) favoured erythromycin; co-amoxiclav was associated with increased necrotising enterocolitis and should be avoided for this indication. Use the antibiotic regimen specified in the NDoH 5th-edition guideline / EML at your facility.
- Expectant management is appropriate for most PPROM without infection, abruption, cord prolapse or fetal compromise: admit (or, per local protocol, monitor closely), give steroids, give magnesium if very preterm, give latency antibiotics, and surveil for infection (temperature, pulse, fetal heart rate, symptoms, serial inflammatory markers) and for fetal wellbeing.
- Timing of delivery: weigh the prematurity risk of staying against the infection risk of waiting. Expectant management is generally continued in the very preterm range while surveillance stays reassuring; nearer term the balance tips towards delivery. There is no universal "deliver at week X" rule — follow the NDoH/GTG 73 framework and individualise to gestation, infection status and local neonatal capability. Any clinical chorioamnionitis mandates delivery and antibiotics regardless of gestation.
- Tocolysis in PPROM is generally not recommended (it risks masking sepsis); a very short course only to enable steroids/transfer may occasionally be considered, but never in the presence of infection.
- Group B streptococcus: provide intrapartum antibiotic prophylaxis per protocol (RCOG GTG 36).
Figure J18.2 — Preterm birth and PPROM management dashboard showing the parallel outcome changers, PPROM latency antibiotics, no-tocolysis red flags and deliver-now triggers.
Get the baby born in the right place — the SA imperative
In-utero transfer of the fetus is almost always safer than ex-utero transfer of a sick preterm neonate. Before any irreversible step:
- Confirm the gestation and viability against local thresholds and decide whether active management is offered.
- Phone ahead. Establish a NICU bed and neonatal team before transfer. A transfer that arrives to no cot is a failed transfer.
- Transfer in utero whenever the mother is stable and delivery is not imminent. Saving Mothers/Saving Babies repeatedly flags failure to refer in time as an avoidable factor.
- Mode of delivery is decided on obstetric grounds: vaginal birth is appropriate for many cephalic preterm deliveries; preterm breech and other malpresentations are common and frequently prompt caesarean (see breech-management and complicated-labour). Continuous fetal monitoring is used where the baby is considered viable and intervention would follow an abnormality (ctg-interpretation).
EMERGENCY DRILLS — act, do not deliberate
CORD PROLAPSE (a true obstetric emergency — commoner with PPROM, malpresentation, high head):
- Call for help — declare an emergency. Summon senior obstetric, anaesthetic and neonatal teams.
- Relieve cord compression NOW: elevate the presenting part with a gloved hand (keep it there); position the woman knee-chest or in steep head-down/left-lateral with hips elevated; consider filling the bladder with ~500 mL saline via catheter to lift the head.
- Minimise handling of the cord (cold and touch cause spasm); do not push it back.
- Expedite delivery by the fastest safe route — usually emergency caesarean if vaginal delivery is not imminent; instrumental/vaginal delivery only if the cervix is fully dilated and delivery is faster. Continuous fetal monitoring meanwhile. (See postpartum-haemorrhage readiness for the birth that follows.)
CLINICAL CHORIOAMNIONITIS / MATERNAL SEPSIS:
- Recognise it: maternal fever, tachycardia, uterine tenderness, offensive liquor, fetal tachycardia, rising inflammatory markers.
- Sepsis Six approach: take blood cultures + lactate, start broad-spectrum IV antibiotics per local protocol, give IV fluids, monitor urine output, give oxygen if hypoxic (RCOG GTG 64).
- DELIVER. Infection inside the uterus is treated by emptying the uterus — do not tocolyse, do not delay for a steroid course. Mode of delivery on obstetric grounds; alert the neonatal team to a septic preterm baby.
DELIVERY OF THE PRETERM/VERY-PRETERM BABY: have the neonatal team present at delivery; practise gentle handling, delayed cord clamping where appropriate and the baby is vigorous; dry/warm (use a plastic bag/wrap for the very preterm to prevent hypothermia), provide inflation breaths and titrated oxygen per neonatal resuscitation guidance (neonatal-resuscitation; initiation-of-respiration).
Figure J18.3 — Emergency-drills action card for cord prolapse, chorioamnionitis/maternal sepsis and very-preterm neonatal handover.
Prevention and the next pregnancy
A woman with a prior spontaneous preterm birth or PPROM is at high risk again. Counsel before discharge and in any future antenatal booking (high-risk-pregnancy-risks): vaginal progesterone for a short cervix or prior preterm birth (progesterone-in-pregnancy); cervical cerclage for selected cervical insufficiency (cervical-cerclage); treating modifiable factors (smoking, infection, optimising HIV/ART). Early dating and risk stratification at booking allow these interventions to be deployed in time.
Red flags / pitfalls
- Doing a digital VE in suspected PPROM. It seeds infection and shortens latency for no diagnostic gain over a sterile speculum. Speculum first; digital only if delivery is imminent and you need cervical information to act.
- Tocolysing through sepsis or abruption. Suppressing contractions while infection or bleeding is the reason for them is dangerous. Contractions and ruptured membranes in the setting of fever mean deliver, not delay.
- Forgetting the single steroid dose. The most avoidable preterm death is one delivered without antenatal corticosteroids when there was time to give the first dose. Saving Babies flags this repeatedly. Give it even if the course will be incomplete.
- Giving co-amoxiclav for PPROM latency. Associated with increased neonatal necrotising enterocolitis — avoid for this indication; use the recommended (erythromycin-based / NDoH-specified) regimen.
- Confusing magnesium for neuroprotection with magnesium for eclampsia. Different indication, different threshold; know which you are giving and why, and monitor for toxicity with calcium gluconate to hand.
- Delivering a viable very-preterm baby where there is no one and nothing to receive it. Transfer in utero, phone ahead, confirm a cot and a neonatal team. Ex-utero transfer of an unwell preterm neonate is far more dangerous.
- Missing cord prolapse when membranes rupture with a high or malpresenting part — examine, and if the cord is felt or seen, run the drill immediately.
- Over-diagnosing preterm labour. Most threatened preterm labour resolves; reserve transfer, tocolysis and steroids for those with genuine cervical change or high pre-test probability, but do not under-treat the woman who is genuinely in early labour at 28 weeks.
- Pre-viable PPROM handled without honest counselling. Prolonged early oligohydramnios risks pulmonary hypoplasia and contractures; the family deserves frank, individualised, non-directive counselling about realistic outcomes within local viability limits.
Evidence anchors
- NDoH — National Integrated Maternal and Perinatal Care Guideline for South Africa (NDoH, 2024): the SA source of truth for gestational thresholds, antenatal corticosteroid and magnesium regimens, latency antibiotics, tocolysis, level-of-care and referral pathways. Confirm exact doses/thresholds against the current edition at your facility.
- Saving Mothers / Saving Babies (NCCEMD), latest triennium: identifies failure of timely in-utero referral and failure to administer antenatal steroids as recurrent avoidable factors in preterm perinatal death.
- South African EML — Hospital Level (Adults): antenatal corticosteroid agent (dexamethasone widely used), magnesium sulphate, tocolytic and antibiotic availability.
- RCOG Green-top Guideline No. 73 — Care of Women Presenting with PPROM ≥24 weeks: diagnosis, expectant management, latency antibiotics, surveillance and timing of delivery.
- RCOG Green-top Guideline No. 74 — Antenatal Corticosteroids: indications, gestational range and benefit window (current; replaces GTG 7).
- RCOG Green-top Guideline No. 36 — Group B Streptococcal Disease (prevention): intrapartum antibiotic prophylaxis in preterm/PPROM birth.
- RCOG Green-top Guideline No. 64 — Maternal Sepsis: recognition and the Sepsis Six approach to chorioamnionitis.
- RCOG Green-top Guideline No. 50 — Umbilical Cord Prolapse: the cord-prolapse drill.
- RCOG Green-top Guideline No. 75 — Cervical Cerclage; progesterone for prevention: secondary prevention in the next pregnancy.
- ILCOR 2025 CoSTR / ERC 2025 Newborn Life Support / AAP NRP: preterm neonatal resuscitation, thermoregulation and delayed cord clamping.
- NICE NG201 — Antenatal care and NICE NG235 — Intrapartum care: cross-reference for risk assessment and intrapartum monitoring frameworks.