Premature birth: could a new combination therapy stop labour and delay birth?

This research was completed on 1 January 2012

Published on 18 February 2010

What's the problem and who does it affect?

Born too soon

An estimated 50,000 babies are born prematurely each year in the UK.^4,5,c Sadly, more than 25 of these babies die each week because of complications that arise from their early birth.^1-3,a,b

Premature birth is also a major cause of disability. Babies who survive an early delivery can develop lifelong conditions such as cerebral palsy, blindness, hearing loss and learning difficulties. Research suggests they may also have an increased susceptibility to some diseases in adulthood, including cardiovascular disease and type 2 diabetes.⁶

The parents, siblings and other close relatives of premature babies can be profoundly affected by the stress of caring for them, and the economic costs are staggering, with major cost implications for the families themselves, the NHS, the education system and social care.

Premature births often happen because the mother goes into labour too soon. Unfortunately, it is difficult to predict which women are at risk – many go into labour without warning. Doctors may try to stop contractions and delay premature labour using drugs called tocolytics, but they are not very effective. We desperately need better ways to tackle this common, serious and costly problem.

What is the project trying to achieve?

Combination treatment

 The researchers are trying to boost the power of a drug called nifedipine. Doctors sometimes use this drug already when they are trying to halt premature labour. However, it can cause the unwanted side effect of low blood pressure in the mother.

Nifedipine works by stopping contractions of muscles in the womb. However, it also stops the contraction of muscles in some other parts of the body, particularly in the walls of blood vessels, which is why it can cause low blood pressure.

The researchers think that giving another drug along with nifedipine might make nifedipine better at halting premature labour without causing the unwanted side effect of low blood pressure. They have exciting new evidence that suggests the other drug might selectively increase the sensitivity of the womb muscles to nifedipine, by over 100 fold, without increasing the sensitivity of muscle cells in blood vessels. They are testing this possibility in the laboratory, using samples of womb tissue donated by pregnant women.

What are the researchers' credentials?

The project team has been researching both the scientific and clinical aspects of premature labour for nearly 20 years. Team members are all internationally recognised for their work on prematurity and the basic science of how the womb functions during labour.

The team has a long history of studying the role of hormones in labour. They also have an interest in studying how the movement of calcium, through channels in the walls of muscle cells in the womb, plays a fundamental role in triggering contractions during labour. Nifedipine, the drug they are studying in this project, works by blocking the movement of calcium through these channels.

The researchers’ two laboratories, at the Universities of Warwick and Newcastle, contain state-of-the-art equipment, perfectly suited for use in this project. They are particularly well positioned, being next door to two of the busiest maternity hospitals in the UK.

Who stands to benefit from this research and how?

Hopes of preventing or delaying premature birth

The researchers are hoping to develop a new, combination drug treatment for women who have gone into labour too soon.

The ultimate hope is that the new treatment will stop or delay premature labour, so stopping babies from being born too soon. The researchers are in the laboratory stages of their work. If the results are promising, they plan to move towards clinical trials.

Finding an effective way to prevent premature birth could bring far-reaching benefits. It could bring huge cost savings. The costs of neonatal care, for example, though staggering in themselves, can be dwarfed by the costs of the long-term care needed by children who develop lifelong conditions such as cerebral palsy, blindness and learning difficulties.

Most importantly, delaying premature labour until a baby is more fully developed could save lives and prevent disability. Premature birth is the biggest killer of babies under one in the UK.^1-3,a,b Over 40 per cent of all the babies who die each year in the UK lose their lives to complications that arise from premature birth.^1-3,a,b Each week that a birth is delayed between 23 and 32 weeks of pregnancy improves a baby’s chances dramatically.

References

1. Office for National Statistics. Health Statistics Quarterly 28 (Winter 2005), 32 (Winter 2006), 36 (Winter 2007)
2. General Register Office for Scotland, Vital Events Reference Tables 2006
3. Northern Ireland Statistics and Research Agency. Registrar General Annual Report 2006
4. Office for National Statistics. Health Statistics Quarterly 35 (Autumn 2007), Table 2.1
5. The Information Centre, Community Health Statistics. NHS Maternity Statistics, England: 2003-04, 2004-05, 2005-06
6. Saigal S, Doyle LW. Preterm Birth 3. An overview of mortality and sequelae of preterm birth from infancy to adulthood. Lancet 2008; 371:261-69
   
   Footnotes
   a. For England and Wales, deaths listed as due to “immaturity related conditions”
   b. For Scotland and Northern Ireland, deaths listed as due to “disorders related to length of gestation and fetal growth”
   c. Calculation made by Action Medical Research based on figures in references 4 and 5 for the number of births a year in the UK and the number of preterm deliveries in England, respectively. Estimate assumes incidence of premature birth is the same for the UK overall as it is for England.