Maternity nurse with patient & baby

Women & Children's Completed Research

The Women and Children’s Research Unit conducts research that aims to improve the care of women and children using Obstetrics and Gynaecology services. This includes pre-conception services though to postnatal care.

The Unit collaborates widely with other disciplines and professions, as well as with women and their companions, to develop ground-breaking research and care, for our patients and throughout the NHS.

Please speak to the person treating you to find out if there is a research study that may be able to help you.

Completed Studies:


Many women have a very different birth experience to what they expected, which can contribute to anxiety and distress. Up to 1.5% of women experience post-traumatic stress disorder at six months following birth, and up to 50% of women suffer stress-related symptoms at two months after Caesarean section and 24% at six weeks after vaginal delivery.

Research has shown that having information about labour, birth and the postnatal period, and feeling in control during labour, are associated with positive psychological outcomes.

Some antenatal education is currently offered to women and their partners as part of routine care. However, many women do not attend these classes and the content and delivery is variable within and between areas.

ACE is a patient-focused intervention that will educate and support women to develop and use coping strategies. It will also equip the midwifery workforce at North Bristol NHS Trust to deliver interactive, skills-based education and enable them to better support patients.

The project aims to improve patient experience, psychological outcomes and staff satisfaction with care.

Focus groups will be held with women and staff to identify current expectations of labour and birth, and to understand how women would like to use coping strategies.

The two interventions (one for women; one for staff) will then be implemented in three community midwifery hubs. Around 50 women in each area will attend. Community midwives will deliver the intervention in addition to usual care. A project midwife will deliver the staff training intervention.

This study is funded by The Health Foundation. Collaborators include the University of Bristol and the National Childbirth Trust.


Project Details
Principal Investigator: Dr Abi Merriel
Local Ref: 4863


Acute Kidney Injury (AKI) is a sudden fall in kidney function. It can happen in pregnancy, during birth and after birth. AKI can cause problems for the pregnancy and the mother and in the longer term for a mother’s health. This study aimed to more clearly define normal kidney function levels in pregnancy, thereby allowing a more accurate diagnosis of Acute Kidney Injury in the future.

Gestational diabetes is a type of diabetes that can develop during pregnancy. Currently, gestational diabetes is diagnosed by a test called an Oral Glucose Tolerance TEST (OGTT), which is performed at around 24-28 weeks of pregnancy and is offered to mother’s who have risk factors for developing gestational diabetes. At times, whilst this result is normal, some women may go on to develop late onset of gestational diabetes and it may go undetected. This study also aimed to look at normal levels of glucose in pregnant women after 32 weeks of pregnancy, using 2 types of test, with a view of finding best way to diagnose late onset gestational diabetes.

Results will be published once the study has completed follow-up in March 2022.

Project Details
Principal Investigator: Dr Christy Burden

Study Completion: 31/03/2022
Local Ref: 


Around one in eight women in the UK require assistance to give birth to their baby vaginally. Currently, doctors use either forceps or a ventouse (a suction cup) to help women have their babies in this manner. This is known as an assisted vaginal birth (AVB). Most mothers and babies do very well after an AVB, and the procedure is usually much better for both mothers and babies than the alternative, an emergency Caesarean section.

However, women and their babies can sometimes be harmed by an AVB. Mothers have a greater tendency to have severe tears of the vagina, and, sometimes, the rectum (back passage) compared to a spontaneous vaginal birth. Mothers may have more pain while healing (usually for one to two weeks) following a birth that has been assisted by forceps or ventouse. Babies may develop bruising over the scalp or face where the forceps or ventouse have been applied. Babies can also, very rarely (around 1 in 1000), sustain more serious harm, such as nerve injuries or bleeding into the brain or eye. Therefore, although AVB is generally very safe and usually better than the alternative (an emergency caesarean section), it is sensible to try to improve the technique to assist a vaginal birth and reduce the risks to both mothers and their babies., No new types of devices to assist vaginal birth have been introduced into practice since the ventouse in the 1950s.

The BD Odon Device is a new device for AVB that has been designed by a team of midwives, doctors and engineers. The BD Odon Device works by placing a cuff of air which is attached to a sleeve, around the baby’s head. The doctor then gently pulls on this sleeve and air cuff to assist the birth of the baby.

In this study, we used the BD Odon Device to help women give birth in cases where it is necessary to assist the birth of the baby. Our study evaluated the safety and effectiveness of the BD Odon device and sought the views of women and healthcare professionals on its use. The information gained from the study has since been used for the large comparative study, ASSIST II.

Project Details
Principal Investigator: Jo Crofts
Study Completion:
Local Ref: 3886


The ASSIST II Study was available to women who planned to have a vaginal birth at Southmead or Cossham Maternity Units and who may have required help assisting the birth of their baby vaginally during the final stages of labour. The study used a novel alternative device to the forceps or suction cup called the Odon Device. The Odon Device uses a soft inflated cuff of air around the baby’s head to help move the baby down the birth canal.

After a 3-month period of follow-up assessments, the study will complete data collection in September 2021.

The ASSIST II Study team aim to publish the results of this research in 2022 and will share the findings with previous participants and members of the public via this website.

Thank you to everyone who has expressed an interest in ASSIST II, to the 900 women who consented to take part, and to the 126 women who allowed us to support their births and follow their postnatal journeys.

To find out more about ASSIST II, please contact the study team via

Project Details
Principal Investigator: Jo Crofts
Study Completion: 05/09/2021
Local Ref: 4572

Impact Diabetes

Healthy eating and staying active during pregnancy help both the mother and baby. We know that women and their families find it hard during the first year after the baby is born to look after their own health as well as their baby’s.

We want to test whether providing women with a health coach and an interactive smartphone app will improve health in pregnancy and the first year after the baby’s birth. The health coach and smartphone app will provide help around healthy eating and exercise in pregnancy, and once the baby is born, help with feeding their baby and active ways to play with them. We are comparing this with giving women the information about healthy eating and staying active in a different way.

We are carrying out this study with colleagues from several hospitals around the world – in Ireland, Spain and Australia.

For more information about this study, visit the bump2babyandme website.

EU Emblem

This project has received funding from the European Union’s Horizon 2020 Research & Innovation programme under grant agreement No 847984

Project Details
Principal Investigator: Dr Christy Burden
Planned end date: In follow-up - 30/06/2023
Local Ref: 4846

IMOX Study

The IMOX study is a multi-centre, double blinded, randomised controlled trial which is comparing the three medicines used for the active management of the third stage of labour.

The third stage of labour is the period of time between the birth of the baby and the delivery of the placenta. There are two ways of managing the third stage of labour, and this study applies to women who are choosing to have an active management of the third stage of labour, following a vaginal birth. Active management involves a one-off injection of a medicine which is designed to help keep the womb contracted thus reducing the risk of a post-partum haemorrhage.

The purpose of the study was to find out which of the 3 medicines, that are currently in use, is the most effective and which allows women to feel as well as possible in the first few hours after their birth.

The study was completed in July 2018. The results are in the process of publication.

Project Details
Principal Investigator: Dr Stephen O'Brien
Study Completion:
Local Ref: 3344


MifeMiso was a randomised, double-blind, placebo-controlled trial – the gold standard for clinical trials:

Randomised: The women who took part were given either the treatment drug (mifepristone) or a placebo – a dummy drug that has no active ingredients. A computer made the selection so it was completely random.

Double-blind: The women in the study weren’t told whether they were taking the mifepristone or the placebo – and neither were their doctors, nurses or midwives. So both the participants and healthcare teams were blinded to this information, to prevent any biases creeping in, while a completely separate group kept a record of who received what.

Placebo-controlled: Around half the women in the study had the active medicine and half (the controls) had the placebo, both in the form of an oral tablet, taken on the day the woman was randomised to the trial. The tablets and packaging looked exactly the same to them and their healthcare teams.

Some women talked to the researchers about their experiences of taking part in the study. The cost of treatment with mifepristone and misoprostol was also compared to misoprostol alone.

Women diagnosed with a missed miscarriage by ultrasound scan in the first 14 weeks of pregnancy could enrol in the study if they were aged 16 or over, chose to have management of miscarriage with tablets (as opposed to an operation) and were willing and able to give informed consent.


  • 711 eligible women took part in the trial. Their average age was 33 years.
  • 696 women were followed all the way through the trial. Of these, 348 women were in the treatment group and 348 were in the placebo group.
  • 42 women,19 in the treatment group and 23 in the placebo group, took part in a discussion about their experiences of the study.

The rate of completion of miscarriage within seven days in the mifepristone plus misoprostol group was 83% (289 of 348 women) compared with 76% (266 of 348 women) in the placebo plus misoprostol group.

In addition, 17% (62 of 355 women) required surgery to complete the miscarriage in the mifepristone plus misoprostol group compared with 25% (87 of 353 women) in the placebo plus misoprostol group.
Treatment with mifepristone did not have any adverse effects.

Having taken part in the study, most women would choose miscarriage management with tablets again and would recommend it to someone they knew who was experiencing a miscarriage. It was important to women that they were supported, felt in control and that the treatment was successful so they didn’t need to have surgery.

The study also found that treatment with mifepristone and misoprostol was less costly than misoprostol alone. Pre-treatment with mifepristone followed by misoprostol is more effective than misoprostol alone for completing a missed miscarriage in women who opt for treatment of miscarriage with tablets.

This research was funded by the UK National Institute for Health Research Health Technology Assessment.

Project Details
Principal Investigator: Dr Jane Mears
Study Completion
Local Ref: 4201


Kidney disease affects about 1 in 30 (3%) women of childbearing age. Most women with kidney disease have successful pregnancies and healthy babies. However, women with kidney disease have an increased chance of more pregnancy complications including early deliveries and smaller babies.  They also may have temporary or permanent damage to kidney function.

At the moment we do not understand why some women develop damage to kidneys during pregnancy. We would like to test your blood and urine at different times during your pregnancy to get more information.  This will allow us to develop tests to predict who is going to have kidney damage and find ways to prevent damage.

Project Details
Principal Investigator: Dr Alison Armitage
Local Ref: 4900


The aim of the PARENTS Study was to evaluate how parental engagement in Perinatal (Stillbirth and Neonatal) death hospital reviews could work in practice and to establish a ‘gold-standard’ for this process that could support this parental engagement across the NHS (and internationally).

In the UK, more than 5,000 babies die before or shortly after birth each year. This can result in a wide range of negative outcomes for parents, families and healthcare staff. 

Parents are rarely involved in the perinatal death hospital review process that takes place after the death of a baby (the Perinatal Mortality Review or “PNMR) and many are largely unaware that it even takes place. However, engaging parents in this process can help them deal with their grief more effectively. Their unique perspective also has the potential to improve care, going forward, by highlighting good practice and areas for improvement.  

The PARENTS Study actively involved parents in the perinatal death review process at NBT’s Southmead Hospital. Involving parents in such a sensitive area is a genuinely novel, yet urgently needed and recommended approach.

The Study was led by our Consultant Senior Clinical Lecturer, Christy Burden, hosted by North Bristol NHS Trust, funded by the Health Foundation and supported by Sands Stillbirth and Neonatal death charity.

PARENTS Study Results:

The impact on patient care was assessed using questionnaires and focus group discussions. The views and experiences of parents, staff and stakeholders was considered to enable the development of a standardised process that is sustainable, useful and has a positive impact on patient care and improve longer term outcomes following bereavement. Approaches such as ours are also helping to promote further transparency and an open culture within the NHS.

The lessons learnt allowed the team to develop a ‘gold-standard’ for engaging bereaved parents in the PNMR following their baby’s death. This gold-standard can be followed using the resources produced as part of the study which are under NBT copyright. To request a copy of the summary and results, please email

This improved and innovative review process, that now gives parents the opportunity to be engaged, has been adopted as part of the Perinatal Mortality Review Tool (PMRT), that is being implemented nationally by our collaborators at the National Perinatal Epidemiology Unit (NPEU) at the University of Oxford.

We want MPs and commissioners to invest in parental engagement. Our vision is to have the option for parental involvement mandated in every hospital and properly resourced.

Project Details
Principal Investigator: Dr Christy Burden
Study Completion: TBC
Local Ref:

The POOL Study

The pool study is a data collection study with the aim of answering the question about the safety of waterbirths.

Information is collected via the hospital’s maternity electronic information system form all women who labour or give birth in water until December 2020, unless a woman specifically opts out of having this data collected.

The study will determine:

  • How many women are using birth pools
  • How many women give birth in water
  • Whether mothers and their babies come to any extra harm as a result of waterbirth.

For babies that need specialist care after their birth, the study will also use the data held by the National Neonatal Research Database(NNRD).

All women who use a pool as part of their labour or birth will be given an information card about the study and they can let the midwife providing their care if they wish to opt out from this study.

Project Details
Principal Investigator: Ms Nichola Bale
Local Ref: 4536

CHANCE: CHronic endometritis ANd unexplained reCurrent miscarriage – The role of the endometrial microbiome

Background: Many people want to become parents. Unfortunately, 5% of couples experience recurrent miscarriage – defined as two or more miscarriages in a row. In more than half of these cases no cause is found.

This has a significant psychological impact on couples and uses many NHS resources. We do not know how to treat women with unexplained recurrent miscarriage and currently only offer supportive care.

A suggested cause of recurrent miscarriage is persistent inflammation of the womb lining. This is known as ‘chronic endometritis’. It may result in an unhealthy environment for an embryo. Chronic endometritis cannot be detected using regular tests; it requires examining a sample of the womb lining in a laboratory. Studies that previously investigated chronic endometritis as a potential cause of recurrent miscarriage are of poor quality and therefore National and International guidelines, The James Lind Alliance, and national miscarriage charities have prioritised this area for research.

Aim: To identify whether women with recurrent miscarriage are more likely to have chronic endometritis than women without recurrent miscarriage, and to identify any bacteria that might be responsible for chronic endometritis. Furthermore, we will investigate if chronic endometritis could cause recurrent miscarriage by changing the distribution/function of cells in the womb lining.

Methods: We will collect a sample of the womb lining from 100 women with a history of recurrent miscarriage and from 100 women who have had a successful pregnancy and no history of recurrent miscarriage (a control group). The control group (as approved by our patient advisory group) will be women undergoing planned “key hole” surgery for another reason but which allows easy sampling of their womb lining too.

If our study shows that chronic endometritis is a likely cause of recurrent miscarriage, we will carry out another study to see if treating chronic endometritis, with targeted antibiotics, increases pregnancy rates. Effective treatment would improve outcomes for our patients and save the NHS and society costs associated with recurrent miscarriage.

The study has been co-designed by women and their partners. Our patient advisory group will also be integral throughout the delivery of the study; from leading the preparation of patient facing documentation, to reviewing any changes made to the study protocol and co-dissemination of our findings through links with Tommy’s charity and The Miscarriage Association.

Sharing the results: Our findings will be presented through national miscarriage charity events and national and international medical conferences. Our results will be published in health journals and freely available to the public. We will work closely with the relevant NHS and professional organisations to ensure that our findings are meaningful and widely and appropriately disseminated.

This study is funded by the National Institute for Health Research (NIHR). Collaborators include the University of Bristol, University College London and the University of Birmingham.

Project Details
Principal Investigator: Dr Islam Gamaleldin
Local Ref: 4383


AZTEC is a research study investigating whether 10 days of treatment with Azithromycin (a common antibiotic), can potentially improve lung outcomes for premature babies when compared to a placebo (dummy medicine).

For more information about this study, visit the AZTEC Trial website

Project Details
Principal Investigator: Dr Richard Wach
Local Ref: 4591

Continuous Glucose Monitoring

This study aims to look at the normal levels of glucose in pregnant women after 32 weeks of pregnancy by using continuous monitoring or CGM (a small device that is placed on the skin and measures glucose in surrounding cells for 7 days) and to compare them with levels earlier in the pregnancy. The aim of the study is to find what normal levels of glucose are after 32 weeks gestation of pregnancy, to then facilitate the future plan to establish the best way to diagnose diabetes at this stage in pregnancy.

Project Details
Principal Investigator: Dr Christy Burden
Local Ref: 4585

MAP-A: The Medication Adherence in Pregnancy- Aspirin Study

Low-dose aspirin prophylaxis is recommended to pregnant women who have risk factors for developing pre-eclampsia. Pre-eclampsia is characterised by high blood pressure and protein in the urine and there is no cure for it except delivery of the baby. Women who have pre-eclampsia can go on to develop serious complications both for themselves and for the baby. Pregnant women are assessed for this risk at the first booking appointment in pregnancy. If they are identified as being at risk they will be recommended to take low-dose aspirin (75-150mg).

We know from talking to women that some find it difficult to, or prefer not to, take the low-dose aspirin that is recommended to them. The aim of the MAP-A study is to find out from women what the barriers and facilitators to taking it are, to inform development of future interventions to support women to take it.

Project Details
Principal Investigator: Dr Christy Burden
Local Ref: 4689


Research tells us that lots of people find it difficult to take medications for their long-term conditions. We know that this can become even more difficult for women when they are pregnant, and for lots of different reasons, including feeling unwell and concerns about the effect of the medications on their baby. Stopping medication in pregnancy can sometimes affect the health of mother and baby during pregnancy but also the mother's health after her baby is born. We would like to find out more about the difficulties that women with long-term conditions experience, and what help they would like from health care practitioners to support them to take their medication.

This study aims to listen to the views of women to help us find the best ways of supporting them to take their medication as recommended.

Project Details
Principal Investigator: Anna Davies
Local Ref: 4702

Shared Decision Making

The aim of this research is to improve shared decision-making during labour and birth, with the purpose of improving women’s experiences of making these decisions. This study will form the foundation for the development of an intervention to improve shared decision making.

We want to improve women’s experience of labour and birth and part of that is for women to lead the decision making during their labour and birth.  Women are often offered interventions to ensure their and their baby’s safety and to optimise their experience of birth. Women may feel vulnerable and are often in pain, it could be considered to be a particularly difficult time at which to have to make decisions about interventions.

We want to improve experience because poor experience can be linked to stress symptoms after a baby is born and, in some studies, has been linked to low mood. Some women who have interventions during their birth describe a poorer experience of birth.

We believe that if we can improve shared decision making, it may improve women’s birth experience.

For more information about this study, visit the NHS England website.

Project Details
Principal Investigator: Dr Abi Merriel
Local Ref: 4656

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North Bristol NHS Trust
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Southmead Hospital
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