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Fetal growth restriction: new hope for babies whose growth becomes dangerously slow in the womb

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What did the project achieve?

“Our laboratory work shows that our new gene therapy is both safe for the mother and baby, as well as effective at boosting the baby’s growth inside the womb,” says Professor Anna David of University College London.

When a baby grows too slowly inside the womb, this is called fetal growth restriction – a complication that affects up to eight percent of all pregnancies.1

Sadly, there are currently no effective treatments that can increase fetal growth and in the most severe cases, the baby may have to be delivered very early, which increases their risk of being stillborn or dying shortly after birth. And those who survive will often experience serious short or long-term health problems that impact on their quality of life.

The causes of fetal growth restriction are complex, but in many cases may involve issues with the mother’s blood supply to the womb around the placenta. So improving this network of blood vessels could help boost the supply of oxygen and nutrients reaching the baby, fuelling their growth.

“Our new treatment involves delivering a gene involved in stimulating blood vessel growth and blood flow into the mother’s circulation to the placenta. We have now carried out extensive tests of this gene therapy in the laboratory, showing it is both safe and can increase the growth of the developing fetus,” says Professor David.

“Based on our encouraging results, we are now preparing to test it in a clinical trial involving women whose babies have stopped growing properly very early on in pregnancy,” she adds.


1,Mandruzzato G et al. Intrauterine restriction (IUGR). J. Perinat. Med. 36 (2008) 277–281.

This research was completed on

Up to eight per cent of pregnant women find their baby develops fetal growth restriction – a serious complication of pregnancy, which can be very dangerous for unborn babies.1 Sadly, the most severely affected babies can be stillborn or die soon after birth. Those who survive are at risk of developing lifelong problems such as cerebral palsy and learning difficulties. Dr Anna David, of University College London, is developing what she hopes will be the first treatment for women whose pregnancies are complicated by fetal growth restriction, in the hope of saving babies’ lives and sparing them from disability.

How are babies’ lives affected now?

“Babies whose growth becomes dangerously slow during pregnancy are not only at increased risk of being stillborn – there are also longer term consequences for their health,” says Dr David. “After birth, these babies can suffer problems such as breathing difficulties, severe infections and bowel damage. During childhood, they may develop further difficulties, including learning disabilities, cerebral palsy and poor vision. They are even at increased risk of heart disease, diabetes and high blood pressure in adulthood.”

At present, no treatment can improve babies’ growth in the womb. Dr David explains: “Expectant parents whose babies are severely affected face a stark choice between allowing the pregnancy to continue, with the strong likelihood that the baby will die in the womb, and agreeing to have their baby very prematurely, in the knowledge that the baby might still lose his, or her, life despite the best possible intensive care.”

Treatments are needed urgently.

How could this research help?

Dr David is leading the development of a new treatment for women whose pregnancies are complicated by fetal growth restriction.

“We have already shown using a laboratory model that our new treatment, which is called maternal VEGF gene therapy, can improve babies’ growth while still in the womb. In this project, we aim to find out whether treatment also improves babies’ health after birth and over the longer term, again using a laboratory model.”

This work will provide important information to help in the design of large-scale tests of the new treatment – planned for 2016 in pregnant women whose babies have stopped growing properly very early in the womb.

Dr David is optimistic: “Our hope is that this new treatment will mean babies are bigger at birth, have a better chance of escaping the disability and ill health that’s linked to fetal growth restriction, and have a better overall quality of life – throughout their lives.”


1. Mandruzzato G et al. Intrauterine restriction (IUGR). J. Perinat. Med. 36 (2008) 277–281.





Project Leader Dr Anna L M David PhD MRCOG MB ChB BSc (Hons)
Project Team Professor Donald M Peebles MD, MRCOGProfessor I C Zachary Ph Zachary PhDDr M Hristova PhD MSc BSc
Project Location Prenatal Therapy Group, Institute for Women's Health, University College London
Project Location Other Centre for Perinatal Brain Research, Department Obstetrics and Gynaecology, University College London Medical SchoolCentre for Cardiovascular Biology and Medicine, University College London Perinatal Brain Repair Group, Institute for Women's Health, University College London
Project duration 2 years
Date awarded 14 August 2013
Project start date 1 May 2014
Project end date 30 June 2016
Grant amount £199,962
Grant code GN2169


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