Premature babies

Some babies arrive earlier than expected. If your baby's born before 37 weeks they’re said to be premature.

Premature babies are likely to be small or underweight and may have health problems. The earlier a baby's born the more health problems they’re likely to have.

Why babies are born early

Babies can be born early if:

  • there's a preterm rupture of membranes (this is the most common cause)
  • you get an infection, such as a urine infection or diarrhoea and vomiting
  • you’re having more than one baby
  • you've a weakness of your cervix
  • you've a health condition such as pre-eclampsia

You're also more likely to give birth early if:

  • you smoke
  • are overweight
  • eat an unhealthy diet

About 6 in 100 babies are born before 37 weeks. The number of babies being born early has stayed roughly the same for the last 10 years.

Twins and multiples

Most twins and triplets are born before 38 weeks, and many earlier than this.

When you’re having multiple babies your:

  • womb's more stretched and that can cause contractions to start
  • waters are more likely to break early too

Twin and multiples pregnancies tend to be a bit more complicated for mum and babies, so sometimes an early delivery's needed to prevent serious health problems. You’ll be monitored closely throughout your pregnancy.

More about twins, triplets and multiple births

If your baby arrives early

If your baby's born before 37 weeks:

  • you may both be cared for in the maternity ward for a few days
  • your baby may need the specialist care of a neonatal unit

Some treatments are only available in certain neonatal units.

More about specialist care for babies

Babies born before 27 weeks

Extremely premature babies born before 27 weeks will need to be born in a hospital which has a Neonatal Intensive Care Unit.

This may mean you need to be moved to another hospital for the birth, or soon after birth, by a team of experts specially trained to do this.

Babies born after 27 weeks

If your baby is over 27 weeks, doctors will advise where the best place to give birth depending on the level of specialist care your baby's likely to need.

If your baby's born between 34 and 37 weeks they could have the same problems as less mature babies, even though they’re a good weight and look like a baby who’s full term.

Health problems in premature babies

The effects of being born early can last just a few days, until your baby reaches their due date, or can carry on affecting their development throughout childhood. Every baby's different. 

All babies born early need time and extra help to cope with the change from life in the womb to being out in the world.

They may have problems with:

  • starting to breathe when they’re born
  • keeping warm
  • keeping breathing regular and keeping blood oxygen levels normal
  • keeping a normal blood sugar level
  • getting rid of bilirubin from their body, which causes jaundice
  • fighting infection

Over the last few years, babies born early have had a greater chance of surviving and developing without any long-term problems.