Groundbreaking trials aimed at saving babies that have stopped growing in the womb are set to begin in London next year.
The study at University College Hospital could give hope to parents of premature babies at risk of being stillborn, dying soon after birth or being born seriously disabled.
About eight in every 100 pregnancies – about 70,000 a year in the UK – is affected by fetal growth restriction. There is no treatment or way of predicting or preventing the devastating condition, which is generally spotted at around 20 weeks.
Parents face a stark choice of delivering their baby early in the knowledge it may die in intensive care, or allowing the pregnancy to continue with the risk of the baby dying in the womb.
The Everrest project, backed by a EU grant of almost six million euros, will enable pregnant women to participate in trials at four hospitals across Europe – UCLH, Barcelona, Hamburg and Lund, in Sweden.
It will study the “severe early onset” of fetal growth problems, where the foetus’s projected weight is less than 600g (1lb 5oz). This occurs in about one in 500 pregnancies.
Women whose baby is discovered at about 20 weeks not to be growing in the womb will be offered the chance to participate in the study and undergo treatment.
This will involve injecting a protein known as VEGF (Vascular Endothelial Growth Factor) into the women’s uterine arteries to increase the blood supply to the placenta, hopefully overcoming so-called “placental insufficiency” and indirectly benefiting her unborn child.
The procedure seeks to stimulate the mother’s natural ability to grow a child, rather than attempt a riskier process of trying to treat the foetus directly.
The condition is caused by a lack of nutrients and oxygen being passed from the mother’s blood to the baby in the womb, via the placenta.
Babies who survive severely restricted growth in the womb are at risk of being born with cerebral palsy, and of developing diabetes and cardiovascular disease in later life.
Dr Anna David, of UCL Institute for Women’s Health, told a UCL lecture to mark International Women’s Day earlier this month: “I think there is a huge unmet clinical need. We see one woman every two weeks at UCLH who has this very severe form [of fetal growth restriction]. There are many more who have babies who are moderately growth-restricted. The potential benefit of treatment is very high.”
Securing relatively small increases in the weight of the foetus and time spent in the womb can have disproportionate benefits. Each extra day in the womb between 24 and 27 weeks gives a two per cent increase in survival rate. Increasing birthweight by 100g reduces the risk of death by 40 per cent.
Subject to ethical and regulatory approval, these will be the first in-human tests. Preliminary tests on donated placentas, and in sheep and guinea pigs, have shown positive results.
Dr David said: “Parents welcome the option for treatment for severe onset fetal growth restriction. There is nothing out there at the moment that will improve the outcome for them or their baby.”