Around 60% of twin pregnancies result in birth before 37 weeks (spontaneous or induced), and around 75% of triplet pregnancies before 35 weeks.

Increased risk of prematurity

With all twins, triplets and more, there is an increased risk of prematurity. According to the National Institute for Health and Care Excellence (NICE) Guideline (section 1.8), your core team should have a discussion with you about the timing and type of birth towards the end of the second trimester (between weeks 24 and 28).

You should be prepared for the possibility that your babies may come early and spend some time in neonatal care. Doctors consider 37 weeks to be full-term for most twin pregnancies. The average length of pregnancy for twins is 36.4 weeks.

Neonatal units

If your babies are born early they might need to spend time at the special care baby unit (SCBU) or the neonatal intensive care unit (NICU).

In just under half of twin births and almost all triplet births, at least one baby has to go into special care for a while. Multiples tend to be small, so they need extra care at the start of their lives.


Neonatal units can sometimes be quite daunting places to begin with and you may think your babies look small and vulnerable amongst all the technology. It’s a good idea to try to visit the neonatal unit on a hospital tour during your pregnancy to prepare yourself for the possibility that your babies may spend some time here. The length of time in a neonatal unit will depend on how early the babies were born and whether they have any medical complications. For more information, download Twins Trust’s booklet A Parents’ Guide to Neonatal Care for Twins, Triplets and More.

It can help to know that many other parents are, or have been, in the same situation as you. Twins Trust have a dedicated Neonatal Facebook group for you to join. Here you can chat with others, find support and share your experiences.

Why could I give birth early?

Being pregnant with more than one baby increases the risk of some conditions, either in you or your babies, which may cause you to give birth prematurely.

We know all parents want to progress to full-term with their pregnancies, however sometimes this is out of your control. What you can do though is be aware of the following:

The most common symptoms and conditions include: High blood pressure in the mother; vaginal bleeding; pre-eclampsia (a condition which affects some pregnant women in the second half of pregnancy or soon after birth); Twin-to-twin transfusion syndrome (a condition affecting some identical twins who share a placenta); pregnancy-induced diabetes in the mother (sometimes called gestational diabetes); selective fetal growth restriction (also known as selective intrauterine growth restriction).

Sometimes, labour can start by itself suddenly. Talk to your health professional if you think you notice anything unusual (different discharge or bleeding).

It’s important to remember that sometimes there is no obvious cause for early labour. Even if the cause is known, it is not always possible to stop a baby from being born early.

Our Complications Guide is designed to help you to understand some of the conditions associated with twin, triplet and higher-order pregnancies. Although these complications are rare, we hope the information in this booklet will help you understand what to expect if you are diagnosed with any of these conditions.


How can I prepare for my babies being born premature?

If health professionals think your babies are showing signs of being born premature you may be given steroid medication (usually in two injections) to help prepare the babies' lungs for breathing. If you’re in labour, medication may be used to try and delay or slow down labour. A midwife, doctor or neonatal nurse will be available to talk to you throughout this time.

Babies born premature or sick may need help straight away with their breathing, or a transfer straight away to the neonatal unit. As a parent, it’s very hard not to be able to hold your babies immediately after birth. You may also be worried that you have not bonded straight away as you had planned. When you first see your babies in the neonatal unit, talk to the staff about how you can become involved in their care, including having skin-to-skin contact. This is shown to help you grow in confidence, help your babies know you are there, and help them to develop too.

Signs of preterm labour

The signs and symptoms of preterm labour are regular contractions of the womb, building up in strength and frequency, sometimes with passage of the mucous plug (‘show’) or breaking of the waters. Premature contractions are a common occurrence in pregnancy, particularly with twins and triplets, and in most cases they are not a sign of preterm labour. However, it can be very difficult to determine if labour is imminent or not and if you experience these symptoms you should inform a healthcare professional immediately. It is likely that you will be advised to go to hospital. Although it is difficult to stop true premature labour, it can sometimes be delayed, giving time to prepare the babies for an early birth.

How big are my babies likely to be?

The average weight of a baby at birth depends on the number of babies and the length of the pregnancy before delivery. Your babies may weigh much the same as each other, or their weights may be very different. The average weight of twins is 2.49kg (5.5lbs) at 37 weeks, whilst it’s 1.80kg (4lb) for triplets.

Monochorionic twins

If your twins share a placenta (monochorionic), your obstetrician may advise that it's safer for your babies to be born at 36 weeks because monochorionic twins are more likely to experience complications.

Are there any impacts of having premature babies?

Reaching developmental milestones may take longer for premature babies compared with babies born at full term. It helps to assess them based on their corrected date (their term due date). Healthcare professionals will be on hand to regularly assess and monitor your baby’s development.

What about later developmental milestones for premature babies?

In the UK, most children start school in the September after their fourth birthday, turning five during their first school year. Legally, they don’t need to start school until they reach their ‘compulsory school age’ ie the term after they turn five. It’s worth considering what is best for your children in terms of starting a time when they are physically and emotionally ready. You will also want to consider whether you’d prefer your children to be together or in separate classes /schools.

Children born prematurely may need some extra attention to help with social and emotional development. Your school should be able to work with you to put tailored plans in place to cater for your children’s needs and make sure they have the correct support in place.

How we can help

Twins Trust have various ways to support you throughout your pregnancy and parenting journey.

In addition to the Neonatal Facebook group we have many other online communities to support you.

Our Twinline service offers a listening ear should you ever talk to someone.

Our Family Support Service offers remote practical support to families with twins, triplets and more and our Family Crisis Support Service offers short term practical support at home to families in times of difficulty.