This information is for general guidance only.

It does not replace advice from your midwife, obstetric team or NICU. Read more about our approach.

Premature birth: signs of preterm labour and what to expect

A premature (or preterm) birth is one that happens before 37 completed weeks of pregnancy. Around 8 in every 100 babies born in the UK are premature. Advances in neonatal care mean outcomes have improved substantially over recent decades, particularly for babies born after 28 weeks.

Premature babies may need support with breathing, feeding, temperature regulation and other functions that would have kept developing in the womb. Monitoring baby's movements and knowing the signs of preterm labour are both key. Twin pregnancy and premature birth often go together, and your antenatal care schedule is designed to pick up on warning signs early.

Prematurity by gestation

Extremely preterm

Before 28 weeks

Rare. Requires intensive neonatal care. Survival has improved significantly: around 80% at 25 weeks, over 90% at 27 weeks at specialist UK centres. Long-term outcomes vary, and the specialist team will discuss your baby's specific situation with you.

Very preterm

28 to 31 weeks

Significant prematurity. Usually several weeks in NICU. Most babies born at this stage survive and do well with support.

Moderate to late preterm

32 to 36 weeks

The most common form of prematurity. Often a shorter NICU stay. Many babies catch up to full-term peers by age 2.

Early term

37 to 38 weeks

Not premature by definition but baby may benefit from some additional monitoring. Outcomes are generally very good.

Signs of preterm labour

Before 37 weeks, call your maternity unit if you have:

  • Regular contractions or tightenings (every 10 minutes or more often)
  • Period-type cramping or pains
  • A gush or trickle of fluid from your vagina (waters breaking)
  • Pelvic pressure, a feeling that baby is pushing down
  • Lower back pain that is new or unusual for you
  • Vaginal bleeding or spotting

If in doubt, always call. Your midwife would far rather hear from you than have you waiting at home.

Causes and risk factors

Preterm labour often has no clear identifiable cause. Known risk factors include:

  • Previous preterm birth (the strongest predictor, around 20-30% recurrence risk)
  • Multiple pregnancy (twins or triplets)
  • Short cervix (identified on transvaginal ultrasound)
  • Infection of the amniotic fluid or cervix
  • Placenta praevia or placental abruption
  • Pre-eclampsia or gestational hypertension
  • Certain uterine abnormalities
  • Smoking, drug use or heavy alcohol use
  • Very low or very high pre-pregnancy BMI
  • Short interpregnancy interval (less than 18 months between births)

What happens when you arrive at hospital

Assessment

  • Vaginal examination to check cervical dilation
  • CTG to monitor contractions and baby's heart rate
  • Ultrasound to check baby's position and cervical length
  • Swabs to check for infection
  • Blood tests

If preterm labour is confirmed

  • Steroid injections (betamethasone), two doses 12-24 hours apart, to help mature the baby's lungs. Offered 24-36 weeks and dramatically improve outcomes.
  • Magnesium sulphate, offered 24-29 weeks (and sometimes 30-33), to protect the baby's brain and reduce cerebral palsy risk.
  • Tocolytics to try to delay labour and buy time for the steroids to take effect. Not always appropriate.
  • Transfer to a centre with appropriate neonatal facilities if needed.

The neonatal unit: what parents need to know

Types of neonatal unit

  • NICU: the highest level of care for the most premature or sick newborns.
  • LCU / HDU: step-down care.
  • SCBU (Special Care Baby Unit): less intensive support.

What you might see

  • Incubator, providing warmth and a controlled environment. Portholes allow you to put your hands in and touch your baby.
  • Ventilator or CPAP machine for breathing support, common in early prematurity.
  • A fine feeding tube through nose to stomach for milk.
  • Monitors measuring heart rate, oxygen, breathing and temperature. Alarms sound frequently and do not always indicate a problem. Ask the nurses to explain each monitor.
  • Lines and drips for medication and fluids.

Your role in the NICU

You are not a visitor, you are your baby's parent. You belong there, and your presence matters enormously.

  • Skin-to-skin (kangaroo care): holding your baby skin-to-skin on your chest, even with tubes and wires. Improves outcomes including weight gain and brain development. Ask staff to show you how.
  • Expressing breast milk: your milk has special properties for premature babies. Even small amounts of colostrum are valuable. The neonatal team will support you.
  • Talking and reading: your voice is comforting and stimulating. Your baby knows you.

Premature baby development

Premature babies are assessed by their corrected age (actual age minus weeks born early) rather than chronological age. A baby born at 32 weeks who is now 3 months old has a corrected age of 1 month, so you compare development to a 1-month-old.

Most premature babies catch up to full-term peers by age 2. Some babies born very early have longer-term additional needs with learning, movement or health, and the NHS provides specialist follow-up care for premature babies.

Practical and emotional support

Practical

  • Hospital travel costs: help through the Healthcare Travel Costs Scheme if you are on certain benefits.
  • BLISS (bliss.org.uk, helpline 0808 801 0322): the UK's leading premature baby charity. Family support workers at most NICUs help with practical and emotional needs.
  • Ronald McDonald House: free accommodation for families at many UK neonatal units, ask your NICU team about availability.

Emotional

  • Having a premature baby is a shock and a grief for the pregnancy and the early weeks you expected. It is normal to feel terrified, overwhelmed, guilty or disconnected at first.
  • NICU teams are experienced in supporting parents — please ask.
  • BLISS peer support and the online community are invaluable.
  • Tommy's (tommys.org) supports baby loss and premature birth families.

Going home

Babies typically go home when they can breathe unassisted, feed fully by breast or bottle, maintain their own temperature, and are gaining weight consistently. For very preterm babies this may be around their original due date, or sometimes earlier.

Some babies go home with an apnoea monitor for breathing pauses. Your NICU team will train you. Premature babies have scheduled developmental checks with a community paediatrician after discharge.

Related guides and tools

Your antenatal appointments→ Premature birth in twin pregnancies→ Baby movements guide→ Emotional support after premature birth→

A note from our team

This guide reflects NHS UK, BAPM (British Association of Perinatal Medicine) and BLISS guidance. If you are currently in NICU with a baby, please lean on the unit team and BLISS. You are doing brilliantly. Read more about us.

Frequently asked questions

What causes premature birth?
Many preterm births have no clear cause. Known risk factors include a previous preterm birth, multiple pregnancy, short cervix, infection, placental problems, pre-eclampsia, certain uterine abnormalities, and maternal factors such as smoking or very low or very high BMI. In many cases, labour simply starts early without a specific trigger.
Will my premature baby be OK?
Most premature babies in the UK do well thanks to advances in neonatal care. Outcomes improve with every additional week of gestation. Babies born after 28 weeks have very good survival rates; many born at 32 weeks or later go on to have no long-term problems. Some babies born very early may have additional needs. Your NICU team will speak honestly with you about your baby's specific situation.
Can I hold my baby in the NICU?
Yes. You are not a visitor, you are your baby's parent. Skin-to-skin (kangaroo care) is strongly encouraged even when your baby has tubes and wires. Ask the nurses to show you how. Research shows it improves weight gain, stabilises heart rate, supports breastfeeding and reduces stress for baby and parent. Even short sessions make a difference.
What is a corrected age for a premature baby?
Corrected age is your baby's actual age minus the number of weeks they were born early. A baby born at 32 weeks who is now 3 months old has a corrected age of 1 month. You use corrected age when thinking about development for the first 2 years, because your baby is doing the things a 1-month-old baby would, not a 3-month-old.
How long will my baby be in hospital?
A general rule is that babies go home around the time of their original due date, though some leave earlier. Babies typically go home when they can breathe unassisted, feed fully by breast or bottle, maintain their temperature, and are gaining weight. Every baby is different and your NICU team will keep you updated on progress.
Can I breastfeed a premature baby?
Yes, and your milk has special properties particularly valuable for premature babies. If your baby is too young or too small to breastfeed directly at first, you can express your milk for it to be given through a feeding tube. Even small amounts of colostrum are precious. The NICU team and neonatal feeding specialists will support you throughout.
What is BLISS?
BLISS is the UK's leading charity for babies born premature or sick. They provide family support workers in many NICUs, a free helpline (0808 801 0322), online resources, peer support and advocacy. They are an invaluable source of practical and emotional help during and after your time in the neonatal unit.