Preterm labour and birth

When giving information and support to women at increased risk of preterm labour, or with suspected, diagnosed or established preterm labour, or having a planned preterm birth (and their family members or carers as appropriate):

• ensure this is given as early as possible, taking into account the likelihood of preterm birth and the status of labour

• follow the principles in NICE's guideline on patient experience in adult NHS services

• bear in mind that the woman (and their family members or carers) may be particularly anxious

• give both oral and written information

• describe the symptoms and signs of preterm labour

• explain about the care that may be offered. [2015]

For women who are having a planned preterm birth or are offered treatment for preterm labour in line with the sections on tocolysis, maternal corticosteroids and magnesium sulfate for neuroprotection (and their family members or carers as appropriate), provide information and support that includes:

• information about the likelihood of the baby surviving and other outcomes (including long-term outcomes) and risks for the baby, giving values as natural frequencies (for example, 1 in 100)

• explanation of the neonatal care of preterm babies, including location of care

• explanation of the immediate problems that can arise when a baby is born preterm

• explanation of the possible long-term consequences of prematurity for the baby (how premature babies grow and develop)

• ongoing opportunities to talk about and state their wishes about resuscitation of the baby

• an opportunity to tour the neonatal unit

• an opportunity to speak to a neonatologist or paediatrician. [2015]

Be aware that, according to the 2021 Mothers and babies: reducing risk through audits and confidential enquiries across the UK (MBRRACE-UK) report on perinatal mortality, women from some minority ethnic backgrounds or who live in deprived areas have an increased risk of stillbirth and may need closer monitoring and additional support. The report showed that across all births (not just those which are preterm):

• compared with white babies (32 out of 10,000), the stillbirth rate is:

  • more than twice as high in black babies (72 out of 10,000)

  • around 50% higher in Asian babies (51 out of 10,000)

• compared with the least deprived areas (23 out of 10,000), the still birth rate is twice as high in the most deprived areas (47 out of 10,000). [2022]

Offer a choice of prophylactic vaginal progesterone or prophylactic cervical cerclage to women who have both:

• a history of spontaneous preterm birth (up to 34+0 weeks of pregnancy) or loss (from 16+0 weeks of pregnancy onwards), and

• results from a transvaginal ultrasound scan carried out between 16+0 and 24+0 weeks of pregnancy that show a cervical length of 25 mm or less.
  
  Discuss the risks and benefits of both options with the woman, and make a shared decision on which treatment is most suitable. [2019, amended 2022]
  
  In April 2024, the only licensed preparation of progesterone for this indication was vaginal 200 mg capsules.

Consider prophylactic vaginal progesterone for women who have either:

• a history of spontaneous preterm birth (up to 34+0 weeks of pregnancy) or loss (from 16+0 weeks of pregnancy onwards), or

• results from a transvaginal ultrasound scan carried out between 16+0 and 24+0 weeks of pregnancy that show a cervical length of 25 mm or less. [2019, amended 2022]
  
  In April 2024, the only licensed preparation of progesterone for this indication was vaginal 200 mg capsules.

When using vaginal progesterone, start treatment between 16+0 and 24+0 weeks of pregnancy and continue until at least 34 weeks. [2019]

Consider prophylactic cervical cerclage for women when results of a transvaginal ultrasound scan carried out between 16+0 and 24+0 weeks of pregnancy show a cervical length of 25 mm or less, who have had either:

• preterm prelabour rupture of membranes (P‑PROM) in a previous pregnancy or

• a history of cervical trauma. [2015, amended 2019]

If prophylactic cervical cerclage is used, ensure a plan is made and documented for removal of the suture. [2019, amended 2022]

In a woman reporting symptoms suggestive of P‑PROM, offer a speculum examination to look for pooling of amniotic fluid and:

• if pooling of amniotic fluid is observed, do not perform any diagnostic test but offer care consistent with the woman having P‑PROM (see the sections on antenatal prophylactic antibiotics for women with P-PROM, identifying infection in women with P-PROM and maternal corticosteroids)

• if pooling of amniotic fluid is not observed, perform an insulin-like growth factor binding protein‑1 test or placental alpha-microglobulin‑1 test of vaginal fluid. [2015, amended 2019]

If the results of the insulin-like growth factor binding protein‑1 or placental alpha-microglobulin‑1 test are positive, do not use the test results alone to decide what care to offer the woman, but also take into account her clinical condition, medical and pregnancy history and gestational age, and either:

• offer care consistent with the woman having P‑PROM (see the sections on antenatal prophylactic antibiotics for women with P-PROM, identifying infection in women with P-PROM and maternal corticosteroids or

• re-evaluate the woman's diagnostic status at a later time point. [2015]

If the results of the insulin-like growth factor binding protein‑1 or placental alpha-microglobulin‑1 test are negative and no amniotic fluid is observed:

• do not offer antenatal prophylactic antibiotics

• explain to the woman that it is unlikely she has P‑PROM, but that she should return for reassessment if there are any further symptoms suggestive of P‑PROM or preterm labour. [2015, amended 2022]

Do not use nitrazine to diagnose P‑PROM. [2015]

Do not perform diagnostic tests for P‑PROM if labour becomes established in a woman reporting symptoms suggestive of P‑PROM. [2015]

As prophylaxis for intrauterine infection, offer women with P-PROM oral erythromycin 250 mg 4 times a day for a maximum of 10 days or until the woman is in established labour (whichever is sooner). [2015, amended 2022]

For women with P‑PROM who cannot tolerate erythromycin or in whom erythromycin is contraindicated, consider an oral penicillin for a maximum of 10 days or until the woman is in established labour (whichever is sooner). [2015, amended 2019]

Do not offer women with P‑PROM co‑amoxiclav as prophylaxis for intrauterine infection. [2015]

For guidance on the use of intrapartum antibiotics, see the section on intrapartum antibiotics in NICE's guideline on neonatal infection, and when applicable also see the section on treatment for women with prolonged prelabour rupture of membranes who have group B streptococcal colonisation, bacteriuria or infection. [2015]

Use a combination of clinical assessment and tests (C‑reactive protein, white blood cell count and measurement of fetal heart rate using cardiotocography) to diagnose intrauterine infection in women with P‑PROM. [2015]

Do not use any one of the following in isolation to confirm or exclude intrauterine infection in women with P‑PROM:

• a single test of C‑reactive protein

• white blood cell count

• measurement of fetal heart rate using cardiotocography. [2015]

If the results of the clinical assessment or any of the tests are not consistent with each other, continue to observe the woman and consider repeating the tests. [2015]

Do not offer emergency cervical cerclage to women with:

• signs of infection, or

• active vaginal bleeding, or

• uterine contractions. [2015, amended 2022]

Consider emergency cervical cerclage for women between 16+0 and 27+6 weeks of pregnancy with a dilated cervix and exposed, unruptured fetal membranes. Also:

• take into account gestational age (being aware that the benefits are likely to be greater for earlier gestations) and the extent of cervical dilatation

• discuss with a consultant obstetrician and consultant paediatrician. [2015, amended 2022]

If emergency cervical cerclage is being considered, explain to the woman (and their family members or carers, as appropriate):

• about the risks of the procedure

• that it aims to delay the birth, and so increase the likelihood of the baby surviving and of reducing serious neonatal morbidity [2015, amended 2022]

If emergency cervical cerclage is used, ensure that a plan is made and documented for removal of the suture. [2019, amended 2022]

Explain to women reporting symptoms of preterm labour who have intact membranes (and their family members or carers, as appropriate):

• about the clinical assessment and diagnostic tests that are available

• how the clinical assessment and diagnostic tests are carried out

• what the benefits, risks and possible consequences of the clinical assessment and diagnostic tests are, including the consequences of false-positive and false-negative test results and taking into account gestational age. [2015]

Offer a clinical assessment to women reporting symptoms of preterm labour who have intact membranes. This should include:

• clinical history taking

• the observations described for the initial assessment of labour in NICE's guideline on intrapartum care

• a speculum examination (followed by a digital vaginal examination if the extent of cervical dilatation cannot be assessed; be aware that if a swab for fetal fibronectin testing is anticipated [see recommendation 1.7.5] the swab should be taken before any digital vaginal examination). [2015]

If the clinical assessment suggests that the woman is in suspected preterm labour and she is 29+6 weeks pregnant or less, advise treatment for preterm labour as described in the sections on tocolysis and maternal corticosteroids. [2015]

If the clinical assessment suggests that the woman is in suspected preterm labour and she is 30+0 weeks pregnant or more, consider transvaginal ultrasound measurement of cervical length as a diagnostic test to determine likelihood of birth within 48 hours. Act on the results as follows:

• if cervical length is more than 15 mm, explain to the woman that it is unlikely to be preterm labour and:

  • think about alternative diagnoses

  • discuss with her the benefits and risks of going home compared with continued monitoring and treatment in hospital

  • advise her that if she does decide to go home, she should return if symptoms suggestive of preterm labour persist or recur

• if cervical length is 15 mm or less, view the woman as being in diagnosed preterm labour and offer treatment as described in the sections on tocolysis and maternal corticosteroids. [2015]

Consider fetal fibronectin testing as a diagnostic test to determine likelihood of birth within 48 hours for women who are 30+0 weeks pregnant or more if transvaginal ultrasound measurement of cervical length is indicated, but is not available or not acceptable. Act on the results as follows:

• if fetal fibronectin testing is negative (concentration 50 ng/ml or less), explain to the woman that it is unlikely she is in preterm labour and:

  • think about alternative diagnoses

  • discuss with her the benefits and risks of going home compared with continued monitoring and treatment in hospital

  • advise her that if she decides to go home, she should return if symptoms suggestive of preterm labour persist or recur

• if fetal fibronectin testing is positive (concentration more than 50 ng/ml), view the woman as being in diagnosed preterm labour and offer treatment as described in the sections on tocolysis and maternal corticosteroids. [2015]

If a woman in suspected preterm labour who is 30+0 weeks pregnant or more does not have transvaginal ultrasound measurement of cervical length or fetal fibronectin testing to exclude preterm labour, offer treatment consistent with her being in diagnosed preterm labour (see the sections on tocolysis and maternal corticosteroids). [2015]

Do not use transvaginal ultrasound measurement of cervical length and fetal fibronectin testing in combination to diagnose preterm labour. [2015]

Ultrasound scans should be performed by healthcare professionals with training in, and experience of, transvaginal ultrasound measurement of cervical length. [2015]

For guidance on the use of other biomarker tests used for the diagnosis of preterm labour, see NICE's diagnostics guidance on biomarker tests to help diagnose preterm labour in women with intact membranes. [2019]

Take the following factors into account when making a decision about whether to start tocolysis:

• whether the woman is in suspected or diagnosed preterm labour

• other clinical features (for example, bleeding or infection) that may suggest that stopping labour is contraindicated

• gestational age at presentation

• likely benefit of maternal corticosteroids (see the section on maternal corticosteroids)

• availability of an appropriate level of neonatal care (if there is need for transfer to another unit). See also NHS England's guidance on saving babies' lives care bundle version 2 (recommendation 5.9).

• the preference of the woman. [2015, amended 2022]

Consider nifedipine for tocolysis for women between 24+0 and 25+6 weeks of pregnancy who have intact membranes and are in suspected preterm labour.

In November 2015, this was an off-label use of nifedipine. See NICE's information on prescribing medicines. [2015]

Offer nifedipine for tocolysis to women between 26+0 and 33+6 weeks of pregnancy who have intact membranes and are in suspected or diagnosed preterm labour.

In November 2015, this was an off-label use of nifedipine. See NICE's information on prescribing medicines. [2015]

If nifedipine is contraindicated, offer oxytocin receptor antagonists for tocolysis. [2015]

Do not offer betamimetics for tocolysis. [2015]

For women between 22+0 and 23+6 weeks of pregnancy who are in suspected or established preterm labour, are having a planned preterm birth or have P‑PROM (see the section on diagnosing P-PROM), discuss with the woman (and her family members or carers, as appropriate) and the multidisciplinary team the use of maternal corticosteroids in the context of her individual circumstances. [2015, amended 2022]

Offer maternal corticosteroids to women between 24+0 and 33+6 weeks of pregnancy who are in suspected, diagnosed or established preterm labour, are having a planned preterm birth or have P‑PROM. [2015, amended 2019]

Consider maternal corticosteroids for women between 34+0 and 35+6 weeks of pregnancy who are in suspected, diagnosed or established preterm labour, are having a planned preterm birth or have P‑PROM. [2015]

Consider a single repeat course of maternal corticosteroids for women less than 34+0 weeks of pregnancy who:

• have already had a course of corticosteroids when this was more than 7 days ago, and

• are at very high risk of giving birth in the next 48 hours.
  
  Where the woman is less than 30+0 weeks pregnant or if there is suspected growth restriction, take into account the possible impact on fetal growth of a repeat course of maternal corticosteroids. [2022]

Do not give more than 2 courses of maternal corticosteroids for preterm birth. [2022]

When offering or considering maternal corticosteroids, discuss the benefits and risks with the woman (and her family members or carers, as appropriate). [2015, amended 2022]

For guidance on the use of corticosteroids in people with diabetes, see NICE's guideline on diabetes in pregnancy. [2019]

For women between 23+0 and 23+6 weeks of pregnancy who are in established preterm labour or having a planned preterm birth within 24 hours, discuss with the woman (and her family members or carers, as appropriate) the use of intravenous magnesium sulfate for neuroprotection of the baby, in the context of her individual circumstances. [2019]

Offer intravenous magnesium sulfate for neuroprotection of the baby to women between 24+0 and 29+6 weeks of pregnancy who are:

• in established preterm labour, or

• having a planned preterm birth within 24 hours. [2015]

Consider intravenous magnesium sulfate for neuroprotection of the baby for women between 30+0 and 33+6 weeks of pregnancy who are:

• in established preterm labour, or

• having a planned preterm birth within 24 hours. [2015]

Give a 4 g intravenous bolus of magnesium sulfate over 15 minutes, followed by an intravenous infusion of 1 g per hour until the birth or for 24 hours (whichever is sooner). [2015]

For women on magnesium sulfate, monitor for clinical signs of magnesium toxicity at least every 4 hours by recording pulse, blood pressure, respiratory rate and deep tendon (for example, patellar) reflexes. [2015]

If a woman has or develops oliguria or other evidence of renal failure:

• monitor more frequently for magnesium toxicity

• reduce or stop the dose of magnesium sulfate. [2015, amended 2022]

For guidance on the use of intrapartum antibiotics in established preterm labour, see NICE's guideline on neonatal infection. [2019]

Discuss the general benefits and risks of caesarean birth and vaginal birth with women in suspected, diagnosed or established preterm labour and in P‑PROM (and their family members or carers, as appropriate). See the section on planning mode of birth in NICE's guideline caesarean birth. [2015]

Explain to women in suspected, diagnosed or established preterm labour and women with P‑PROM about the benefits and risks of caesarean birth that are specific to gestational age. In particular, highlight the difficulties associated with performing a caesarean birth for a preterm birth, especially the increased likelihood of a vertical uterine (classical) incision and the implications of this for future pregnancies. [2015, amended 2022]

Explain to women in suspected, diagnosed or established preterm labour that there are no known benefits or harms for the baby from caesarean birth, but the evidence is very limited. [2015]

Consider caesarean birth for women presenting in suspected, diagnosed or established preterm labour between 26+0 and 36+6 weeks of pregnancy with breech presentation. [2015]

Wait at least 60 seconds before clamping the cord of preterm babies unless there are specific maternal or fetal conditions that need earlier clamping. [2015, amended 2022]

Position the baby at or below the level of the placenta before clamping the cord. [2015]