Information alert

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Overall, most women (over 90%) spontaneously give birth to their baby after 37 weeks of pregnancy, called term delivery. Approximately 10%, or 1 in 10 women spontaneously give birth to their baby preterm before 37 weeks of pregnancy. Most babies born preterm do well, but a few have long term problems.

At UCLH we offer a specialist antenatal service for women who have risk factors that increase the chance of preterm birth.

The Preterm Birth Clinic is for women who have an increased chance of delivering their baby preterm because:

  • they have had a previous spontaneous preterm birth or a late miscarriage
  • their womb is an unusual shape e.g., unicornuate
  • they have had a previous delivery by Caesarean section at full dilatation
  • their cervix has been found to be shorter than normal by ultrasound scan (<25mm) before 26 weeks
  • they have had a stitch (cervical cerclage) placed in their cervix in a previous pregnancy or in this pregnancy
  • they have had surgery on their cervix (neck of the womb):
    • one or more cone biopsy
    • two or more LLETZ (Large Loop Excision of the Transformation Zone).

Women who have had a single LLETZ will be offered a cervical length assessment at their dating ultrasound scan (11-14 weeks) and their anomaly ultrasound scan (19-22 weeks). If their cervix is a short length (<25mm) they will be offered an appointment in the Preterm Birth Clinic.

The aim of the clinic is to support women by monitoring them closely in the first two-thirds of pregnancy and acting appropriately to try to prevent a preterm birth. Often we can discharge women from the clinic once they reach 22 weeks but we sometimes see women until around 28 weeks.

Women will then be seen regularly in midwifery-led or consultant obstetrician-led care every 3-4 weeks. If you are not booked to deliver your baby at UCLH we will liaise with your local booking hospital to plan for ongoing care locally.

The Preterm Birth Clinic is held every Wednesday morning in the Maternal Fetal Assessment Unit (MFAU), 1st floor of the EGA wing and is run by:

  • Professor Anna David - Consultant Obstetrician and Maternal Fetal Medicine Specialist
  • Dr Kasia Maksym – Consultant Obstetrician and Gynaecologist (O&G)

Senior and junior doctors, student doctors and student midwives are also in the clinic. Please let us know if you would prefer not to have students in the room during your appointment.

Because of the nature of the clinic, we often need to see women urgently and frequently, which makes our clinics oversubscribed. We aim to see you on time but we will inform you if we are running late. Please ask MFAU Reception if you have any delays to your appointment. We hope that your visit to our clinics meets your expectations. We invite you to complete a patient satisfaction questionnaire.

In our clinic we are looking for new ways through research to improve the care of pregnant women and their babies by preventing preterm birth. Since 2008 we have helped to develop new methods to predict which women are at risk of preterm birth, and we have tested out novel treatments to prevent preterm birth. We have also worked with pregnant women and their partners who have experienced a preterm birth to identify what their research priorities are. We are now using predictive tests in clinical practice that we were researching 10 years ago.

All of our research projects have been formally reviewed by an ethics committee. It is up to you to decide whether or not to take part after reading an information leaflet. If you do decide to take part you will be given the information sheet to keep and asked to sign a consent form. If you decide to take part you are free to withdraw at any time and without giving a reason. If you do not feel able to take part it will not in any way to affect the care you and your family receives.

1st visit

On your 1st visit you will first be seen by the clinic midwife and doctors. Your appointment may take up to an hour so please allow this amount of time. A detailed history will be taken. You will then be offered swabs (taken from the vagina and vulva using a speculum examination) to check for the following infections:

  • Bacterial vaginosis
  • Group B Streptococcus

These infections are not common, but women who have them may have a higher risk of preterm birth. Treatment may reduce the risk. If infection is found we will arrange treatment with the appropriate antibiotics.

We may offer you low dose aspirin (75-150mg) to start by 16 weeks if you had a small baby or pre-eclampsia previously or if you have an increased chance of these complications.

Every visit 

At every appointment we will test your:

  • Urine
  • Blood Pressure
  • The length of your cervix

At your 1st and every subsequent visit, your urine will be tested for signs of a urine infection either using a dipstick or by sending it to the laboratory to be cultured. This is because urinary tract infections can trigger preterm labour. If infection is found we will arrange treatment with the appropriate antibiotics. After treatment another urine sample should be sent to the laboratory to check that the infection has cleared.

Every visit will involve your blood pressure being monitored. Raised blood pressure in pregnancy can increase the risk of preterm birth.

In the Preterm Birth Clinic at every visit, the length of your cervix will be measured. To get a clear view of the cervix we will perform a scan through the vagina (trans-vaginal scan). This is performed by inserting a specially designed ultrasound transducer into the vagina. Please let us know if you have an allergy to latex so that we can use a latex-free probe cover. This type of scan does not harm the baby, or cause bleeding or miscarriage. The length of the cervix can give a guide as to the chance of you delivering your baby preterm. Antenatal_care_women_increased_risk_preterm_baby_1.PNG

Research studies in women at high risk of preterm birth, but who have no symptoms of labour1 show that cervical length predicts the likelihood of preterm birth. We use the QUIPP

algorithm that was developed from a research study done in our clinic1 to give a personalised risk of preterm birth. It provides information on the chance of birth within 1, 2 and 4 weeks of the scan, and birth before 30, 34 and 37 weeks.

Sometimes the top portion of the cervix (internal os) opens up but the bottom part (external os) remains closed. This is called “funnelling” and is associated with a higher chance of delivering preterm.

If your cervix is short or if there is funnelling we will discuss with you the best management. This may include closer monitoring, progesterone treatment or cervical cerclage (stitch). We may offer you a course of steroids to mature the baby’s lungs or admission to hospital.

Maternal steroids

When babies are born very preterm their lungs are “stiff” and the baby needs to make a big effort to open up their airways to breathe. A course of steroids (2 injections over 12 or 24 hours) given to the mother can help the baby inflate their lungs and breathe better if they are born early. We may recommend giving you a course of steroids if there appears to be a high chance of you delivering your baby preterm.

Progesterone

The hormone progesterone may reduce the risk of preterm birth in women who have a history of spontaneous preterm birth. A large study “EPPPIC” combining data from lots of clinical trials found that giving women vaginal progesterone pessaries did reduce the chance of early preterm birth before 34 weeks in singleton pregnancies2. The results also suggested possible reductions in serious baby complications and low birthweight infants. We will discuss with you if progesterone treatment may be of benefit in your situation.

Cervical cerclage (“stitch in the cervix”)

Majority of cervical cerclage is a minor surgical procedure performed by an obstetrician that aims to keep your cervix closed by placing a stitch into your cervix. This is usually

done under general anaesthetic. The cervix is reached through the vagina using a speculum. Having a cervical cerclage put in place may mean that the neck of your womb is less likely to undergo changes that can cause it to open. Your baby is therefore held safely inside the womb and your chances of getting an infection or going into labour too early are also reduced. There are a few risks of the procedure and not all women benefit. We will discuss with you whether cervical cerclage may benefit your pregnancy.

An elective cervical cerclage may be recommended if you have delivered your baby preterm in previous pregnancies or if you have had surgery or trauma to your cervix that shortens or weakens it. In this case the cervical cerclage is usually placed after your dating scan, at 13 - 15 weeks of pregnancy.

Ultrasound-indicated cervical cerclage: In some cases, small changes to your cervix such as shortening or funnelling can be detected on ultrasound scans. In this case we may arrange for you to have a cervical cerclage as soon as possible to try to prevent any further changes.

Preterm Clinical Network Database

Every year we audit our patient data for quality purposes and to improve our service. We are members of the UK Preterm Clinical Network, a group of doctors, midwives and researchers who are working to prevent preterm birth and the problems that occur when babies are born preterm. We use the Preterm Clinical Network Database to store information about the women we see in our Preterm Birth Clinic. This includes information about why they may be at risk of preterm birth, any treatments they have had, and whether they had their babies early. We use this database to audit our service.

Separately, we will ask for your consent to share your information in this database anonymously with the UK Preterm Clinical Network for research purposes. The database is funded by an NHS Innovations Challenge Prize and Tommy’s charity.

1. Will continuing to work increase the chance of delivering my baby preterm?

There is no evidence that continuing work will increase your risk of preterm birth. It may be appropriate to consider some time off work if your occupation involves standing for long periods or long-distance travelling. Some women feel a short period away from work reduces their stress levels, particularly if they have previously had a late miscarriage or preterm birth. We can supply a letter for your employer if it is felt advisable that you take some time off work.

2. Can I exercise in my pregnancy?

There is no risk associated with starting or continuing moderate exercise during pregnancy. Any sport that may cause abdominal trauma, falls or excessive joint stress should be avoided.

3. Can I have sex during my pregnancy?

There is no evidence that having sex causes preterm birth. But we would advise you not to have sexual intercouse if:

  • your placenta is low-lying. Once the placenta has moved away later in pregnancy it may be safe to resume sexual intercourse. You should await advice from your obstetrician or midwife.
  • you have vaginal bleeding.
  • you have had a cervical cerclage placed. You should avoid intercourse until you have been seen again in the Preterm Birth Clinic.

4. Can I do anything to prevent me from delivering my baby early?

Women who smoke have an approximate two-fold higher risk of delivering their baby preterm and we advise smokers to stop smoking immediately. Getting professional help increases the chance that you will stop smoking. UCLH can provide support, can prescribe nicotine patches and you can self-refer to UCLH stopping smoking services. There are benefits even if you stop smoking in the middle of pregnancy.

Douching the vagina (rinsing of the vagina) interferes with the vagina's normal self-cleaning and with the natural healthy bacteria living in the vagina. Douching is associated with bacterial vaginosis and may increase the chance of preterm birth. We advise all women not to douche their vagina.

Some diets are associated with a lower risk of preterm birth. Eating a diet rich in vegetables, fruits, oily fish, water as beverage, whole grain cereals and fibre rich bread is beneficial. Increasing the intake of omega-3 long-chain polyunsaturated fatty acids in the diet before 20 weeks of pregnancy either by eating oily fish regularly or in a supplement (500mg-1g per day) has been linked to a lower chance of preterm birth.

5. Should I be concerned by any symptoms?

You should speak to a midwife if you experience any of the following symptoms.

  • Increasing watery vaginal discharge
  • Increasing abdominal pain
  • Vaginal bleeding
  • Increasing feeling of pressure on your vagina

6. Where can I get more information?

7. Donations to support our research for patient benefit

The UCLH Charity Prenatal Therapy Fund financially supports our research studies into the causes of preterm birth, is used to develop novel treatments to prevent it, and for staff training.

To donate to the fund please go to this link: http://www.justgiving.com/UCLH-prenatal-therapy-fund

The Prenatal Therapy Fund is a discretionary fund within UCLH Charity. The charity’s administration costs are covered by investment income, so every £1 that is donated to the Prenatal Therapy Fund goes directly to charitable activities. UCLH Charity work with the Preterm Birth clinic team to ensure that donations are used as effectively as possible.

UCLH Charity provides support for patients, staff and medical research at UCL Hospitals. It is a registered charity, number 229771.

Tommy’s has launched the National Centre for Preterm Birth Research and UCLH is proud to be part of the centre at UCL.

  1. Abbott et al. Obstetrics & Gynecology 2015;125:1168-76 https://pubmed.ncbi.nlm.nih.gov/25932845/
  2. Stewart et al. Lancet 2021;397:1183-1194 https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)00217-8/fulltext

UCL Hospitals cannot accept responsibility for information provided by other organisations.

Contact the Midwife emergency hotline in Maternal Fetal Assessment Unit: 020 3447 9400 (Please choose option 2)

Contact the Preterm Birth Clinic midwife via the Fetal Medicine Unit – 0203 447 6150

https://www.uclh.nhs.uk/our-services/find-service/womens-health-1/maternity-services/ask-your-midwife


Page last updated: 24 January 2025

Review due: 01 January 2027