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Preterm birth

Specialist care for pregnant women at risk of having their baby early

Based at St Thomas' Hospital, the preterm surveillance clinic provides specialist care to pregnant women who are at high risk of having their baby early.

We want to improve your care by providing support, treatment and information during and after your pregnancy.

The preterm surveillance clinic team also aims to improve your care by providing guidance to hospital and community staff – see 'Information for health care professionals' below.

Information for women

In the UK, around 8% of babies are born early (before 37 week's gestation). You have been asked to come to the clinic because you are at higher risk of having your baby early.

  • Why you have been asked to see us

    The preterm surveillance clinic aims to provide extra care for women who may have a higher risk of having a baby born too early. This can be for a number of reasons, such as:

    • previous birth before 34 weeks
    • previous late miscarriage
    • the 'waters' (amniotic sac) have broken before 34 weeks in a previous pregnancy

    • previous surgery to the cervix after an abnormal smear test

    • an unusually shaped womb (uterus)

    • women expecting more than one baby.

    Often we will see you in the clinic two or three times to be able to reassure you that your pregnancy is progressing well and then discharge you from the clinic at around 24 weeks of pregnancy.

    Sometimes we may think it is useful to monitor you more regularly and we may be able to offer you treatments that reduce the risk of preterm birth.

  • What will happen at your appointment

    You will usually speak with a midwife who will ask about your history and discuss your personalised plan of care.

    • You may be offered a transvaginal ultrasound scan of your cervix, where an ultrasound probe is placed into the vagina. Your bladder should be empty for this scan.

    • If you are over 18 weeks pregnant, you may also be offered a vaginal swab test (fetal fibronectin) to help predict your risk of an early birth. This is done with a speculum and then a swab (like a cotton bud) is placed in the vagina for a few seconds. Your swab result is usually ready after 10-25 minutes.

    • Sometimes emergencies and unexpected events can increase waiting times. We appreciate your patience and will keep you informed if delays occur.

    There are some things which make the swab test less reliable. We recommend that you avoid the following for two days before you attend the clinic:

    • sexual intercourse
    • vaginal douching (this involves flushing the vagina with water for the purpose of cleaning).

    The tests and screening that we do help us to check that you and your baby are safe. We might recommend you have other tests or treatment. We will work with you to plan your care and any treatment you may need.

  • When to seek advice

    Sometimes there are signs that you may be going into labour. Often the signs may not lead to preterm labour but it is important to let your midwife know so you can get advice.

    These signs may include:

    • period-like pains or cramps which come and go
    • fluid leaking from the vagina
    • bleeding from the vagina.

    If you think you may be in labour, do not wait for your next appointment in the preterm surveillance clinic. Call the Maternity Assessment Unit (MAU) immediately on 020 7188 1723 or 020 7188 1722.


In utero transfer (PDF 1.25Mb)

Preterm birth surveillance clinic (PDF 369Kb)

Transabdominal cerclage (PDF 188Kb)

Contact details

  • The preterm surveillance clinic

    The preterm surveillance clinic runs on Wednesday at Fetal Medicine Unit, 8th floor, North Wing, St Thomas' Hospital Antenatal Clinic, 8th floor, North Wing, St Thomas' Hospital.

    Call the appointment line on 020 7188 8003.

  • Preterm midwives

    You can get in touch with the preterm midwives, Monday to Friday, 9am-5pm, telephone 020 7188 3634.

  • General advice

    For general advice the maternity helpline is available Monday to Friday, 10am-6pm (except bank holidays), telephone: 020 7188 8760.

    Tommy’s charity also has useful advice. Visit the Tommy's website or call 020 7398 3400.

Information for health care professionals

Please see our referral guidelines (PDF 143Kb).

Women booked at St Thomas' Hospital can be referred by their midwife or obstetrician and book an appointment directly through the fetal medicine unit (FMU) reception. If you have any problems please contact the preterm midwives by calling 020 7188 8003.

Women not booked at St Thomas' Hospital can be referred by their GP through the e-Referral service (e-RS). If you have any problems, please contact the preterm midwives by calling 020 7188 3634.