Fifteen million and rising—the number of premature births every year

BMJ 2012; 344 doi: (Published 03 May 2012) Cite this as: BMJ 2012;344:e3084
  1. Anne Gulland
  1. 1London

A worldwide study of preterm births has found that 15 million babies are born before 37 weeks’ gestation every year, with one million of those babies dying from complications.

The report, published by a coalition that includes the World Health Organization and the charity Save the Children, found that the proportion of preterm babies was rising in nearly every country with reliable data, mainly high and middle income countries. Prematurity is the leading cause of death in newborns and the second leading cause of death in children under the age of 5 years, but a lack of data on preterm births at the country level has hampered action in low and middle income countries, the report says.

Joy Lawn, one of the authors and director of global evidence and policy at Save the Children, said it was time that the world recognised prematurity as a major child health problem.

“People have never seen this as a problem before, as we haven’t had the numbers. These babies die very quickly on the labour ward, and they often aren’t even registered,” she said.

The report divides preterm births into three categories: extremely preterm, any baby born earlier than 28 weeks; very preterm, between 28 and less than 32 weeks; and moderate to later preterm, 32 to less than 37 weeks.

The world’s average rate of preterm births is 11%, and the country with the highest rate is Malawi, where 18% of all births are preterm. The US rate of 12% is higher than that in many low income countries, including Somalia, Lesotho, and Afghanistan.

Risk factors for preterm births include high or low maternal age; maternal infections such as HIV, syphilis, and urinary tract infections; multiple pregnancies; having babies closely together; smoking; and being underweight. The report warns that the global epidemic of obesity is “likely to become an important contributor to global preterm birth.”

However, not all preterm births are spontaneous. In France and the United States nearly 40% of babies are born early on the advice of medical staff, twice the 20% in Scotland and the Netherlands. In the US the rise in the number of what the report calls “provider initiated” births is partly responsible for the high rate of preterm births.

However, survival rates are also important. In rich countries 90% of babies born between 28 and 32 weeks’ gestation survive without impairment, but in many poor countries this proportion is only 30%.

Lawn said that more than 80% of preterm births were at 32 to 37 weeks and that these babies could be saved without the kind of high tech, expensive neonatal interventions seen in rich countries.

Cost effective interventions to help babies survive include “kangaroo care,” where the baby is held skin to skin on the mother’s chest to keep warm; prescribing antibiotics to babies; and giving the mother steroid injections in labour to encourage lung maturity in the infant and prevent respiratory problems.

Lawn said that it was important to debunk the myth that all preterm babies needed expensive neonatal intensive care.

“In the UK and the US the neonatal mortality was halved before anyone started doing neonatal intensive care. Neonatal intensive care is important for babies born at less than 28 weeks, but that’s just 5% of the distribution,” she said.


Cite this as: BMJ 2012;344:e3084