Preterm birth (birth before 37 weeks gestation) has not been accorded the global priority due it by international health policy makers, researchers and donor organizations, in part because of a lack of data on the worldwide extent of the problem. As a first step in helping fill this data gap, the March of Dimes in October 2009 issued a white paper on preterm birth, with estimates from the World Health Organization, of the rate of preterm birth for the world as a whole and by UN region. In considering the data, it is important to note that only singleton births and birth to mothers with no known medical conditions were counted. Thus, the estimates most likely significantly underestimate the true magnitude of the problem.
The report paints a grim picture. It shows that in 2005, an estimated 13 million babies were born preterm, almost 10 percent of total births worldwide, representing a global prevalence of preterm birth of 9.6%. About one million deaths in the first month of life (or 28 percent of total newborn deaths) are attributable to preterm birth. The toll of preterm birth is particularly harsh in Africa and Asia where over 11 million (85%) of all preterm births occur. In contrast, 900,000 babies are born premature in Latin America and the Caribbean, and about 500,000 preterm births occur in both Europe and North America (Canada and the United States combined) on an annual basis. The high absolute number of preterm births in Africa and Asia is associated with the substantially greater number of deliveries and fertility levels in these two regions in comparison to other parts of the world.
When considering the rate of preterm birth, the report data paint a very different picture. The highest rate by UN region is found in Africa where 11.9 percent of births are preterm. The WHO data show a rate in North America of 10.6 percent. The lowest rates are in Australia/New Zealand and in Europe, where they are 6.4 and 6.2, respectively. Where good-quality trend data are available, preterm births also seem to be increasing in numbers. In the USA, for example, the rate of preterm birth has increased by 35% in the past 25 years, because of factors such as a rise in the use of assisted reproductive technologies.
The report notes that although more research is needed to find the interventions that are effective at preventing preterm births, there is a lot that can be done now. For example, in high-income countries there needs to be more focus on preconception health. Women planning a pregnancy should be encouraged to adopt a healthy lifestyle, including giving up tobacco smoking if they smoke and losing weight if they are overweight.
In developing countries, there are several simple low-cost interventions that can help promote a healthy pregnancy outcome, such as treating malnutrition in women before and during pregnancy, treating high blood pressure and diabetes, and monitoring pregnancies for problems. Care for preterm babies can also be low cost and effective, such as keeping the baby warm, treating infections, and providing adequate nutrition.
A forthcoming Global Report on Preterm Birth from the March of Dimes and WHO will be issued late next year with the first ever country-by-country estimates of preterm birth prevalence. The March of Dimes and WHO expect that the data in the White Paper and in the forthcoming Global Report will serve as a catalyst for policy makers, researchers, donors, clinicians and the general public to address preterm birth, a global public health problem that has been, to date, under-recognized, under-counted and under-funded.