Preterm Birth and Preterm Prelabour Rupture of Membranes (PPROM)

There are 4 maternity-led strategies that should be offered/considered dependent on gestation to reduce mortality and morbidity in cases of preterm labour and planned preterm birth. See below sections for detailed guidance on each. These form part of the Scottish Patient Safety Programme (SPSP) perinatal optimisation package.

• Delivery at unit with level 3 NICU service when appropriate.
• Antenatal corticosteroids.
• Magnesium sulphate.
• Delayed cord clamping.

In addition:

Tocolysis may be considered to facilitate in-utero transfer and administration of steroids.

Intrapartum antibiotics for group B strep prophylaxis reduce the rate of neonatal sepsis.

Thermal care of the neonate.

Delivery unit

• Borders General Hospital has a level 1 Special Baby Care Unit. Aim to transfer to a maternity unit with a level 2 Neonatal unit if 28-32 weeks and a level 3 unit if less than 28 weeks
• MDT discussion between Consultant Obstetricians and Neonatologists should follow re safety and feasibility of transfer. If transfer recommended contact the In-utero Coordination Service (ScotSTAR) on 03333 990 210
• Delivery in a NICU significantly improves survival and neurodevelopmental outcomes and should be accommodated if safe to do so
• Factors to consider when considering IUT:
  • Gestation
  • Maternal condition
  • Current fetal condition including background risk factors and fetal monitoring
  • Active labour/progress of labour.
  • Neonatal and obstetric unit activity and cot/bed status.
• Be aware that transfer takes time. It is appropriate to commence both steroids and magnesium prior to transfer. Magnesium bolus can be given +/- infusion can be started, discontinued for transfer and restarted in receiving hospital. This approach can ensure babies get the best chance of full optimisation
• Perform a pretransfer pause
• Prior to transfer, reassess the patient clinically to ensure they remain appropriate for transfer. Ensure observations are up to date and this may also warrant repeat vaginal examination (digital vaginal examination (VE) or speculum) to assess for possible progress in labour if there has been delay since last assessment

Antenatal Corticosteroids

Antenatal corticosteroids reduce perinatal mortality and morbidity for premature babies.

Maximal benefit occurs in pregnancies that deliver 24 hours after and up to 7 days after administration of the second dose of antenatal corticosteroids.

There is no/very limited benefit if birth occurs >7 days following steroid administration (RCOG 2022).

Maternal corticosteroid therapy has been shown to reduce the risk of neonatal death and morbidity even if delivery occurs within the first 24 hours. A steroid course should be commenced even if delivery is anticipated with 24 hours.

There is no evidence of other significant maternal harm caused by steroid administration. Steroids do not increase maternal infection rate but may worsen already present systemic infection therefore caution and individualised plan should be used in this scenario. 

Administration:

Betamethasone: two doses of 12 mg IM given 24 hours apart (or 12 hours apart if delivery anticipated within the 24 hours)

Or Dexamethasone: two doses of 12mg IM given 24 hours apart (or 12 hours apart if delivery anticipated within the 24 hours)

See Diabetes guidelines regarding use in diabetic pregnancies as steroids cause maternal hyperglycaemia. Women treated with insulin will need additional insulin therapy and may need a variable rate infusion.

Recommendations per gestation

There is some variation in national and international guidance regarding the use of steroids per gestation. Benefits and risks in late preterm birth remain controversial.

NHS Borders recommendations for steroid administration per gestation

2+0- 23+6: individualised discussion

Babies born at this gestation have the highest risk of mortality and severe morbidity (BAPM). Discussion should be had involving senior obstetrician, neonatologist and the pregnant person/parents regarding the decision for either survival or comfort focused care and may be offered steroids thereafter.

24+0- 34+6: Offer steroids

Offer steroids to all women in preterm labour or having a planned preterm birth.

34+6 – 36+6: Consider steroids

Consider steroids. This should involve shared decision-making with the parents. Risks and benefits of steroids at late preterm gestations should be discussed. Take into account other risk factors such as caesarean birth, known underlying neonatal conditions and fetal growth restriction.

Repeated course of steroids

Repeat courses of steroids are not routinely recommended but may be considered in certain circumstances. This would be a consultant decision taking into account timing of steroids and likelihood of imminent birth.  There is poor evidence of benefit from steroids when birth is > 7 days from administration.

NICE (2022) and WHO advises to consider a single repeat course if <34+0, steroids >7 days ago and are at very high risk of giving birth in the next 48 hours.

Magnesium sulphate for fetal neuroprotection

Preterm delivery is a known risk factor for cerebral palsy. Magnesium Sulphate reduces this risk.

Magnesium sulphate should be offered to all women <30 weeks’ gestation (individualised decision 22+0-23+6) where delivery is planned or expected within 24 hours.

Offer magnesium sulphate to those who are in established preterm labour of having planned preterm birth within 24 hours. Ideally it should be given in the 24 hours prior to birth for maximum efficacy.

Bolus +/- infusion can be commenced prior to in-utero transfer, discontinued for transfer and restarted in receiving unit.

30- 33+6 Do not routinely offer.  May occasionally be considered in certain circumstances

Administration and dosage of magnesium sulphate

A 4g bolus dose should be given followed by an infusion of 1g/hour until birth or for 24 hours whichever is sooner.

If magnesium sulphate use is for preterm optimisation only (i.e. not pre-eclampsia), discontinue at delivery.

For planned delivery commence infusion as close to 4 hours before delivery as practical. For unplanned situations, ideally at least 4 hours of magnesium should be given but treatment should not be withheld if delivery is anticipated before this.

If there is maternal and/or fetal compromise delivery should not be delayed to allow administration of magnesium. Multiple pregnancies should receive the same dose and treatment. Anaesthetic and neonatal medical staff should be aware of the decision to give magnesium sulphate.

Contraindications: allergy, severe aortic stenosis, cardiogenic shock.

Caution: oliguria, renal impairment, pulmonary oedema

The dosing and monitoring regime are the same as given in severe pre-eclampsia and eclampsia.

Loading Dose (bolus):                      

• 4 grams IV over 15-20 minutes through an Alaris pump @ 120ml/hr
• 40 mls of 10% Magnesium Sulphate (4 amps)

Maintenance Infusion Dose:

• IV infusion 1 gram Magnesium Sulphate per hour 10mls/hr

Maintenance Infusion Preparation:

• 5 grams (50 mls of 10% Magnesium Sulphate (5amps)
• Infusion rate is 1 gram (10 mls) per hour via a syringe driver

Infusion is maintained at 1 gram/hr for 24 hours provided:

• Respiratory rate > 14 per minute
• Urine output > 25mls/hour, and
• Patellar reflexes are present

Use the same monitoring for patients with preeclampsia/eclampsia receiving magnesium sulphate.

Delayed Cord clamping (DCC)/optimal cord management

DCC results in a significant (32%) reduction in mortality in preterm babies.

When survival focused care is being offered, all babies <34 weeks should receive deferred cord clamping for a minimum of 60 seconds.

Practicalities

• We now routinely offer DCC to all babies in our unit, however the impact on preterm babies is significant and we should ensure preterm babies in particular receive this.
• When birth is expected or planned, there should be discussion with neonatal team regarding attendance. Initial stabilisation of the baby can be offered with the cord intact. This may also involve placing the baby in plastic bag as part of thermal management.
• Neonatal attendance at safety briefs prior to planned preterm caesarean births is of benefit for planning of this and should be part of routine practice.
• Whenever possible timing of cord clamping should be guided by the neonatal team in conjunction with the obstetric team.
• Decision to perform earlier cord clamping due to concerns regarding the condition of the baby should be a shared decision with the neonatal team.
• Take care to assess cord length to prevent disruption of cord from traction.
• Administration of active 3^rd stage drugs (oxytocin/syntometrine) should be administered as normal at normal time.
• DCC should be passive with the baby ideally at the level of the placenta or below. The cord should not be routinely milked.

DCC special circumstances

• General anaesthesia is not a contraindication to DCC.
• Initial management of caesarean related traumatic bleeding may be able to be managed whilst the cord is intact. This is for a relatively short time and given DCC results in a significant reduction in neonatal mortality, every effort should be made to provide this. This may involve e.g. the use of Green Armitage clamps on bleeding vessels.
• If the placenta delivers with the baby, BAPM recommend that DCC can still continue for 60 seconds (the beneficial effects are not in relation to oxygenation from the placenta but in relation to blood volume) and the placenta can be held at a level above the baby.
• At caesarean birth for DCDA twins, if possible delivery of second twin should continue whilst DCC being performed for first twin.

Contraindications to DCC:

• The need for maternal resuscitation for massive, acute haemorrhage
• Ruptured vasa praevia, snapped cord or other trauma to the cord vessels which will result in haemorrhage from the baby
• Hydrops

Individualised decision:

• Abruption
• FGR with abnormal umbilical artery Doppler.
• Monochorionicity with twin-twin transfusion syndrome

Tocolysis for preterm labour

There is no clear evidence that tocolytic drugs improve neonatal outcomes and therefore it is reasonable not to use them.

Tocolysis can be considered <33+6 to allow administration of steroids and or transfer to an appropriate unit for neonatal care dependent on gestation.

Tocolytic drugs are contraindicated when delayed delivery may have adverse effects on maternal health or may keep the fetus in a potentially hostile environment. (E.g. known chorioamnionitis)

Contraindications include:

Following discussion with the on call obstetric consultant, if tocolysis is deemed necessary then the agent of choice is Nifedipine.

Dose: Nifedipine Modified Release 20 mg TID x 48 hrs.

Side effects: hypotension, tachycardia, headache, nausea, flushes

Contraindications: allergy, severe aortic stenosis, cardiogenic shock.

Caution:  concurrent administration of Magnesium Sulphate. May cause maternal hypotension.

If Tocolysis has been commenced but labour is progressing: Stop Nifedipine and start Magnesium Sulphate for fetal neuroprotection if <30 weeks

• Symptoms of preterm labour/history
• Diagnosis of established preterm labour
• Suspected/threatened preterm labour
• Adjuncts to the diagnosis of preterm labour
• Management when assessment is not in keeping with preterm labour/suspected preterm labour

Symptoms of preterm labour/history

It is important to note that symptoms and signs of preterm labour may be subtle and preterm labour should be considered in people with the below symptoms. Delay in diagnosis could lead to missed opportunities for perinatal optimisation interventions (steroids, magnesium, transfer) and timely counselling.

Symptoms may include:

• Abdominal Cramps- with or without diarrhoea
• Backache- low, dull constant
• Contractions/ cramping/tightening
• Vaginal Discharge (increase in the amount of discharge) or bleeding
• un-Easiness- feeling “not right”
• Fetal movements /urinary Frequency– changed
• Gush of fluid loss - preterm rupture of membranes
• Heaviness or pelvic pressure—the feeling that the baby is pushing down

Differential diagnosis

Have a low threshold for suspicion of preterm labour

Alternative diagnoses may include:

Assessment

This should involve:

• Detailed history
• Observations
• Maternal examination including abdominal palpation
• +/- sterile speculum +/- digital vaginal examination
• Fetal assessment (auscultation or CTG dependent on gestation and scenario)
• +/- Actim Partus testing – please see below
• +/- cervical length assessment using transvaginal ultrasound – please see below

History

• Establish patient’s background including risk factors for preterm labour including:
  Previous PPROM/preterm birth, uterine anomaly, LLETZ x 2, full dilatation caesarean birth, Asherman’s, smoking, Multiple pregnancy, PPROM or cervical suture in this pregnancy
• If uterine activity/cramping enquire re frequency, duration, pattern.
• Determine if any symptoms of infection
• Enquire re urinary or gastrointestinal symptoms
• Enquire re PV loss (bleeding, discharge, liquor)

Examination/initial Investigation

• Maternal observations
• Perform urinalysis
• Abdominal examination and palpation. Assess for uterine activity but also abdominal tenderness, peritonism, uterine tenderness as part of consideration of differential diagnoses
• Fetal heart rate assessment by doppler or CTG
• Sterile speculum examination to assess for cervical dilation + high vaginal swab
• If unable to assess cervical dilatation adequately, offer digital vaginal examination to assess cervical length, dilatation and effacement
• MSU if suggestion of UTI
• Blood tests. FBC, CRP should be taken when preterm labour is diagnosed, along with group and save

Diagnosis of established preterm labour

If cervix is effaced and 2 or more cms dilated, treat as preterm labour.

Initial management:

• IV access, FBC, G+S, CRP
• Ultrasound for presentation
• MSSU, LVS if HVS not already taken
• Admit to labour ward
• Steroids based on above guidance
• MgSo4 based on above guidance
• In-utero transfer is less likely to be appropriate if > 4cm with ongoing uterine activity but may occasionally be considered depending on gestation, dilatation, uterine activity, maternal and fetal assessment. Distance to accepting unit should also be considered. Regular reassessment of the clinical situation should take place particularly prior to transfer.
• Inform Consultant Obstetrician
• Inform Neonatal team - A consultant to consultant discussion regarding any preterm women is advised.
• Ideally neonatal medical review and counselling for patient.

Suspected/threatened preterm labour:

Symptoms of preterm labour where assessment confirms the possibility of preterm labour but rules out established labour. This could include regular palpable uterine activity, other strong features in history, patient at high risk of preterm labour or some cervical change but <2cm dilated.

Management of suspected preterm labour

• Consider use of Actim Partus (see below)
• Consider the use of cervical length ultrasound assessment
• Admission for observation if >32 weeks with ongoing symptoms or signs of preterm labour
• In-utero transfer is likely to be appropriate <32 weeks in all patients with ongoing symptoms or signs of preterm labour
• FBC, CRP, +/- consider G+S
• Ultrasound for presentation
• MSSU, LVS if HVS not taken
• Consider In-utero transfer
• Repeat cervical assessment in 2- 4 hours if ongoing symptoms.
• Treat as preterm labour if cervical change (effacement/dilatation ≥ 2cm)

Adjuncts to the diagnosis of preterm labour

Fetal Fibronectin testing (NICE: 30+0 – 33+6 weeks’ gestation)

Hologic are discontinuing production of fibronectin testing kits nationally, therefore fFN testing has been removed from NHS Borders.

Actim Partus testing

Actim Partus involves a cervical swab sample.

The rapid test is based on highly specific monoclonal antibodies that bind to the phosphorylated form of insulin-like growth factor binding protein-1 (phIGFBP-1). PhIGFBP-1 is produced in the decidua, but leaks into the cervix when the decidua and chorion detach.

A negative Actim Partus result indicates a very low chance of labour in the next 1-2 weeks.

Recommendation for use of Actim Partus

< 30 weeks: base management on history and examination and manage as established/suspected preterm labour as above.

30+0 -36+6 weeks

Consider use in women with symptoms of preterm labour without cervical dilatation and effacement. Do not use in PPROM or PV bleeding.

Negative result

As Actim Partus has a high negative predictive value, if no ongoing regular uterine activity or other clinical concerns consider discharging patient with advice to return if ongoing or new symptoms of preterm labour.

In some situations where there is a significantly high risk of preterm labour or the patient may find it difficult to return quickly, admission for observation may still be considered but perinatal optimisation/transfer does not need to be started.

Positive Actim Partus result

Be aware that Actim Partus has a lower and highly variable positive predictive value in studies. This means that a large number of women with positive result will not go on to labour.

• Do not give steroids/magnesium/ arrange in-utero transfer based on positive result alone.
• Transvaginal ultrasound should be used to guide ongoing management and if 15mm or less treat as preterm labour. See section below
• If ongoing uterine activity, repeat clinical assessment of patient in 2- 4hours including repeat cervical assessment (speculum +/- digital VE).
• If cervical change: steroids +/- Magnesium sulphate/transfer to LW/ in-utero transfer dependent on change/dilatation

Performing Actim Partus testing

Collect a cervical secretion sample using a speculum

Lubrication gel can be used

Cervical swab. Hold the swab in for 10-15 seconds

Extract the specimen

Insert the swab into the extraction buffer. Swirl around vigorously for 10-15 seconds, and discard the swab.

Activate the test

Insert the yellow dip area into the extracted specimen

Wait until you see the liquid front enter the result area

Remove the dipstick from the buffer and place it in a horizontal position

Interpret the test result

• A positive result can be read as soon as it becomes visible.
  Two blue lines (including faint) = positive
• A negative result should be confirmed at 5 minutes.
  One blue line = preterm or imminent delivery is highly unlikely
• No lines= invalid

Actim Partus can be used:

• With lubricating gel
• Following intercourse

Contraindications:

• Ruptured membranes
• Vaginal bleeding. (manufacturer advises against use in moderate/severe and to only perform when no blood present)

Cervical length assessment by transvaginal ultrasound

Cervical length scanning (transvaginal scan by appropriately trained clinician) should be considered between 30+0 - 33+6 weeks in cases of suspected preterm labour. A cervical length < 15mm should be treated as preterm labour. The QUiPP app calculator can be used to help determine risk of preterm labour. 

Management when assessment is not in keeping with preterm labour/suspected preterm labour

Discharge may be appropriate where:

• History and examination findings are not in keeping with preterm labour and are normal.
• There is no palpable uterine activity
• The cervix is not effaced and is <2cm dilated
• Actim Partus testing is negative (if used as per above guidance)
• Observations are normal and clinical assessment is otherwise reassuring
• Differential diagnoses have been considered
• Consideration has been given to the woman’s social circumstances/ability to recognise ongoing symptoms and return.

• Principles
• Maternal monitoring
• Fetal monitoring in preterm labour
• Fetal blood sampling (FBS)
• Use of Fetal scalp electrode (FSE)
• Progression in labour
• Antibiotics in labour
• Mode of birth

Principles

• Discuss with senior neonatal medical staff and patient should ideally have a neonatal consultation
• Update neonatal team re progress and to ensure able to be present prior to birth
• Provide one to one midwifery care
• Provide perinatal optimisation with steroids, +/-magnesium, deferred cord clamping at birth
• Recommend intrapartum antibiotic prophylaxis
• Ensure room temperature appropriate
• Check resuscitaire
• Provide regular maternal monitoring. Be alert for developing chorioamnionitis.
• Continuous CTG monitoring
• Aim to provide deferred cord clamping in majority of situations.

The on-call Obstetric Consultant should be notified when a patient is admitted in preterm labour. They should be in attendance for all preterm births in theatre and any preterm birth in labour ward with fetal or maternal concerns. 

Maternal monitoring

Perform baseline observations of HR, BP, temperature, RR.

Take bloods for FBC, CRP, G+S, MSSU and LVS if not already taken.

Regularly assess maternal observations and uterine activity. This should be performed as per standard care in the first and second stage of labour.

Fetal monitoring in preterm labour

In practice it is reasonable to offer CTG to those ≥ 26+0 weeks gestation.

Use of Fetal scalp electrode (FSE)

FSE should not be routinely used in preterm labour.

Progression in labour

Preterm labour may progress more slowly than term labour. This may allow time for administration of steroids/magnesium.

Intervention to augment labour would not normally be recommended unless there are maternal or fetal concerns. This should involve discussion with the on call obstetric consultant.

The neonatal team should be contacted when the patient is in the second stage.

Antibiotics in labour

Offer all women in establish preterm labour antibiotics for group B streptococcus prophylaxis.

Be vigilant for signs and symptoms of chorioamnionitis and if suspected change the antibiotic regime.

Mode of birth

The mode of birth should be individualised.

Planned caesarean birth should be considered for breech presentation as there is an increased risk of head entrapment during vaginal birth particularly at earlier gestations.

Planned caesarean birth may be the most appropriate mode of birth in preterm birth particularly < 34 weeks e.g. for severe growth restriction/pre-eclampsia.

• Definition and background
• Diagnosis of PPROM
• Management if PPROM confirmed
• During admission
• Timing of birth if no preterm labour
• Outpatient Management of PPROM
• Evidence regarding outcomes in extreme PPROM

Definition and background

Rupture of membranes prior to 37+0 with no evidence of labour.

3% pregnancies are affected

Occurs in 30-40% preterm births

Complications: Neonatal morbidity and mortality from prematurity, pulmonary hypoplasia, sepsis, and cord prolapse. Maternal sepsis (chorioamnionitis), abruption.

 Diagnosis of PPROM

• Take a detailed history and include
  • Timing of suspected PPROM
  • Colour/odour of fluid
  • Any bleeding
  • Any pain /contractions/cramping or tightening
  • Fetal movements
• Undertake and document maternal observations
• Measure symphysis-fundal height, fetal lie and presentation
• Fetal heart rate assessment (CTG from 26+0 weeks).
• Perform sterile speculum examination and high vaginal swab (HVS)
  • Consider performing after the mother has adopted the left lateral position for 20 -30 minutes (limited evidence). If a pool of liquor is seen diagnose PPROM
• HVS may grow group B streptococcus (GBS) colonisation which is relevant to recommendations re timing of birth. In the absence of PPROM it may point to other causes of vaginal discharge (e.g. candida, bacterial vaginosis)
• When a pool of amniotic fluid is not clearly observed, consideration should be given to testing for placental alpha microglobulin-1 (PAMG-1) (AmniSure)
  • AmniSure detects PAMG-1: sensitivity 99%, specificity 98%. AmniSure can be used in the presence of semen, minimal amounts of blood, vaginal infection, after intercourse, after a vaginal examination, and in the presence of a minimal amount of water-based lubricant. DO NOT USE with active vaginal bleeding.
• If the results of the AmniSure test are negative and no amniotic fluid is observed, do not offer antibiotics and explain PPROM is unlikely but that the woman should return for re-assessment if symptoms persist.
• If results are positive, NICE and RCOG recommendation is not to use the test results alone to decide what care to offer the woman, but also to take into account her clinical condition, medical and pregnancy history and gestational age, and either offer care consistent with PPROM or re-evaluate at a later stage.

Management if PPROM confirmed

• Obtain MSSU, LVS if HVS was not taken at time of speculum.
• Do not routinely perform digital examination of cervix. Assess if there is cervical dilation during speculum examination. Digital examination should be considered if unable to visualise a long closed cervix (as this may be due to cervical dilatation) use sterile pack and gloves.
• Take blood tests for WCC (FBC) and CRP.
• There is a high risk of preterm labour in the next 48 hours. Recommend admission for observation for 48 hours.
• Offer steroids dependent on gestation, see below.
• Discuss admission with neonatal staff. Ideally women should have the opportunity for neonatal counselling regarding expectations should their baby deliver.
• In-utero transfer should be considered if <32 weeks or if known underlying fetal issues
• Medical review if suggestion of preterm labour
• Perform bedside ultrasound scan for presentation
• There is no evidence of benefit from the use of tocolytics following preterm premature rupture of membranes, therefore withhold.
• If there is no evidence of chorioamnionitis, commence antibiotics.
  • Oral Erythromycin 250mg QDS for 10 days, or until labour is established (whichever is sooner).
  • NICE recommends an oral penicillin if the woman is allergic to erythromycin

Subsequent management

• Consider the need for antenatal corticosteroids – see section above.
• Discuss the risks and benefits of antenatal steroids at late preterm gestation.
• Arrange ultrasound for growth, LV and umbilical artery Doppler.
• Discuss with neonatal team – this should include a medical team discussion

If there is evidence of infection or fetal compromise seek senior obstetric opinion and consider delivery.

Signs of Chorioamnionitis:

• Maternal pyrexia, hypothermia, tachycardia, tachypnoea
• Uterine tenderness
• Offensive discharge
• Raised WCC/CRP ( NB. Steroids elevate WCC and the trend of WCC is more important than the actual values)
• Fetal tachycardia
• Meconium staining – this is almost diagnostic of sepsis in preterm pregnancy

In cases of suspected chorioamnionitis:

• Sepsis 6 bundle
• Commence intravenous antibiotics
• Delivery will need to be planned
• Mode of birth will depend on gestation, presentation, obstetric history, if in active labour, and maternal wishes.

During admission

• Regular maternal observations 4 hourly.
• Fetal monitoring method and frequency will depend on gestation. If appropriate, twice daily CTG during admission.
• Medical review if suggestion preterm labour, infection or new clinical concerns. Aim for timely diagnosis to allow transfer to labour ward and neonatal attendance at delivery.
• The decision to offer outpatient care to women with PPROM, following a period of in-patient care, should be made on an individual basis. Factors including past obstetric history, support at home and distance from the hospital should be taken into account in discussion with the woman about her preferences.

If preterm labour occurs: treat as per preterm labour guidance.

If there is no evidence of infection or fetal compromise and preterm labour does not develop after 48 hours:

Assess for discharge home

Arrange follow-up through PAU/Ward 16 and book the woman into the next available Consultant ANC.

Timing of birth if no preterm labour

Timing of birth should be discussed with the woman and usually decision made through own ANC/with consultant involvement.

In women with PPROM and no contraindication to continuing the pregnancy birth should be planned at 37 weeks gestation. Intrapartum GBS prophylaxis should be offered irrespective of GBS status (RCOG GBS prevention).

If GBS present.

For those at more than 34+0 weeks gestation it may be beneficial to expedite delivery if a woman is a known GBS carrier.

For those with evidence of GBS colonisation in the current pregnancy or in previous pregnancies, the perinatal risks associated with preterm delivery at less than 34+0 weeks of gestation are likely to outweigh the risk of perinatal infection.

Intrapartum GBS antibiotic prophylaxis should be offered in labour.

Outpatient Management of PPROM

(After a period of minimum 48 hours as an inpatient)

Prior to discharge, women should be advised of the signs and symptoms of chorioamnionitis and under what circumstances they should seek specialist advice. Give them the RCOG patient information leaflet (“When your waters break prematurely”)

The following women may not be suitable for outpatient management:

• Non-cephalic presentation
• Long distance from BGH or difficulties with transport
• Social issues that may prevent compliance with outpatient surveillance

Woman should be reviewed twice per week in Ward 16/PAU. The following should be reviewed:

• Well-being of woman, colour of liquor, any pain, fetal movements
• Checks observations, including temperature (if HR >100bpm, temperature < 36°c or > 38°c, RR>20 or O2 saturation <94% on/air then registrar review required).
• Examine abdomen
• Check WCC/CRP
• Check fetal heart (110-160bpm) – if any concerns commence CTG
• Perform fortnightly ultrasound scans for growth, LV and umbilical Doppler (unless concerns prompt more frequent monitoring)
• CTG monitoring is not routinely required unless there are concerns regarding fetal movement, maternal wellbeing, infection, uterine activity, fetal growth or umbilical artery Doppler.
• Ensure follow up is also in place with woman’s consultant (likely via antenatal clinic) for consultant oversight and delivery planning
• If there are concerns regarding the above or there is suspicion of chorioamnionitis, then senior obstetric opinion should be sought

In-utero transfer (IUT)

• Borders General Hospital has a level 1 Special Baby Care Unit. Aim to transfer to a maternity unit with a level 2 Neonatal unit if 28-32 weeks and a level 3 unit if less than 28 weeks
• MDT discussion between consultant obstetricians and neonatologists should follow re safety and feasibility of transfer
• The In-utero Coordination Service (ScotSTAR) should be contacted on 03333 990 210
• Good communication between units is essential for patient safety
• Aim to complete the Preterm Birth Preparation tab on Badger prior to transfer
• Complete the Preterm Perinatal Checklist for all admissions/transfers <34 weeks gestation
• Perform a pretransfer pause
• Prior to transfer, reassess the patient clinically to ensure they remain appropriate for transfer. Ensure observations are up to date and this may also warrant repeat vaginal examination (digital vaginal examination (VE) or speculum) to assess for possible progress in labour if there has been delay since last assessment
• In-utero transfer is generally not considered appropriate for women >4cm dilated
• In-utero transfer should not be undertaken for women with abnormal CTG

Benefits of steroid use < 35 weeks evidence summary

RCOG 2022 guidance on corticosteroid use assessed most up to date evidence including a Cochrane review of 27 studies, 11925 babies.

Between 24+0-34+6 If birth was 24- 48 hours following administration, steroids were shown:

-with high certainty to reduce:

Perinatal mortality with RR 0.85, Neonatal mortality RR 0.78, Respiratory distress syndrome RR 0.71

-With moderate certainty to reduce:

Intraventricular haemorrhage RR 0.58, Developmental delay RR 0.51

There was a reduction in respiratory morbidity if birth >48 hours but < 7days following steroids.

Extreme preterm gestations

 <25 weeks there is evidence of benefit throughout the literature and published guidance.

RCOG 22 guideline committee included data from a systematic review of 9 observational studies with 13, 443 babies. This showed that steroid administration was associated with:

Reduced mortality (odds ratio [OR] 0.48, 95% CI 0.42–0.55),

Reduced IVH/periventricular leukomalacia (PVL) (OR 0.70, 95% CI 0.63–0.79).

Antenatal corticosteroids were associated with significantly reduced neonatal mortality at 22, 23 and 24 weeks; the benefit for severe IVH/PVL was significant only at 23 and 24 weeks.

Risks and benefits of steroids in late preterm pregnancies evidence summary

Data from RCOG antenatal corticosteroids green top guideline 74 (2022) regarding steroid use between 35+0 – 36+6 weeks.

Benefits:

Likely to reduce need for respiratory support. 146/1000- 116/1000, RR 0.8, NNT 33.3

Harm:

Likely to increase neonatal hypoglycaemia. 150/1000- 240/1000, RR 1.6, NNH 11.1 (this data included babies from 34+0)

May increase psychiatric and behavioural diagnoses in children born at term, NNH 38.8(this data included babies from 34+0)

Evidence of harm comes from observational studies.

There is mixed evidence regarding possible neurodevelopmental risks of late preterm steroids.

Gyamfi-Bannerman C et all published data from an RCT in 2024:

949 babies from 34-36 weeks gestation (479 betamethasone, 470 placebo) completed the DAS-II (differential ability scales) at a median age of 7 years. There were no differences in the primary outcome, a general conceptual ability score less than 85, which occurred in 82 (17.1%) of the betamethasone vs 87 (18.5%) of the placebo group (adjusted relative risk, 0.94; 95% CI, 0.73-1.22). No differences in secondary outcomes (Gross Motor Function Classification System level and Social Responsiveness Scale and Child Behaviour Checklist scores) were observed.

Repeated course(s) of steroids evidence summary

Concerns regarding possible adverse effects from maternal administration of repeated doses of corticosteroids have been raised.  NICE 2022 reviewed the evidence: There is evidence of reduced birth weight however mean difference was 114g. Reductions were greater at administration gestations <30 weeks, if given < 7 days interval and with increasing number of repeated courses.

There is some evidence of reduction in need for respiratory support (NICE 2022). RCOG 2022 suggests incidence of respiratory support of 395/1000 without and 311/1000 with administration of 2nd course steroids. RR 0.91 and NNT 11.9.

There was no good evidence of an effect on perinatal mortality, neonatal admission, intraventricular haemorrhage, growth at 2 years, neurodevelopmental delay. The NICE 2022 committee agreed that a single repeat course may be beneficial in certain circumstances when first course was >7 days previous and preterm birth was imminent but that with  multiple repeat courses the effects on birthweight outweigh any benefits.

The definition of a “repeated course” varies in the multitude of studies. Many used 2 x 12mg betamethasone and WHO recommends considering 24mg betamethasone in divided doses as a “course”.

See https://www.nice.org.uk/guidance/ng25/evidence/b-evidence-review-for-effectiveness-of-repeat-courses-of-maternal-corticosteroids-for-fetal-lung-maturation-pdf-11078990750

Magnesium sulphate evidence summary

The rate of cerebral palsy in surviving neonates is estimated to be 14.6% at 22-27 weeks’ gestation, 6.2% at 28-31 weeks’ gestation and 0.7% at 32-26 weeks gestation.

Maternally administered magnesium sulphate reduces the risk of cerebral palsy in babies <30 weeks gestation by 30% when given in the 24 hours prior to birth.

30-33+6 weeks

Magnesium Sulphate use within this gestational age range to reduce the risk of cerebral palsy is not supported by robust evidence (RCOG impact paper 2011, NICE 2015, 2022), and is therefore not recommended in this GG&C guidance, however NICE suggests consideration of its use. There may therefore be consultant level decision for its use due to documented specific risks i.e. suspected fetal infection, severe FGR or other increased priori risk of neonatal neurological dysfunction

Actim Partus evidence summary/details

There is less high quality evidence for its use vs fFN and is not yet currently recommended in NICE preterm birth guidance.

Sensitivity: 77% pooled

Specificity:  81% pooled

Positive predictive value:  39-86%

Negative predictive value: 92-98%. Pooled 98%

Manufacturers promote use from 22 weeks. However, Given the above statistics, along with NICE’s previous recommendation that fFN should not be used prior to 30 weeks (highest risk babies where there should be a lower threshold for admission +/- optimisation) we do not currently recommend routine use of Actim Partus <30 weeks.