Preterm births higher among deprived mothers, despite equal care

Despite improvements in obstetric care services, women from deprived areas are still more likely to give birth to a very preterm baby compared with mothers from more affluent areas, finds a study published on bmj.com today. Yet survival rates and provision of care was similar for infants from all areas, suggesting that neonatal care provision is equitable. A finding in contrast to many other areas of health care where socioeconomic inequalities in survival and access to care are common.

These findings highlight an urgent need to better understand the link between deprivation and risk of preterm birth, say the authors.

In developed countries such as the United States and the United Kingdom, preterm birth is a major cause of infant mortality. The risks of death are highest in those born very preterm (before 33 weeks' gestation) and in those from the most deprived areas.

Little is known, however, about how the survival of very preterm infants varies with deprivation.

So researchers at the University of Leicester set out to assess the socioeconomic inequalities in survival and provision of neonatal care among very preterm infants in the UK.

They tracked 7,449 very preterm infants born 1998-2007 in the former Trent region of England from the onset of labour until discharge from neonatal care. A deprivation score was calculated for each infant using postcode data.

The authors point out that the data came only from one English region, which has about 54,000 births a year, representing one in 12 UK births, so the findings can't necessarily be extrapolated to different places. However, Trent does have a particularly good prospective dataset about births.

Their results show that mothers from the most deprived areas were nearly twice as likely to have a very preterm infant compared to those from the least deprived areas and consequently there were nearly twice as many deaths due to very preterm birth in the most deprived areas.

However, among very preterm infants, survival rates and neonatal care provision showed little variation across all deprivation measures. This suggests that, although socioeconomic inequalities in preterm birth rates persist, deprivation does not seem to be a barrier to accessing and receiving neonatal care.

As such, the authors believe that understanding the link between deprivation and risk of preterm birth should be a major research priority. "It seems highly likely that such work could lead to public health strategies that would reduce the costs not only of neonatal care but also attached to the long term health problems suffered by some of these babies," they conclude.

"Further progress on preventing preterm birth in general and reducing socioeconomic inequalities in preterm birth is unlikely to occur without a better understanding of the role of socioeconomic factors," say Ron Gray from the University of Oxford and Marie McCormick from Harvard School of Public Health in an accompanying editorial.

This study did not look at individual factors such as smoking, ethnicity, and history of previous preterm birth. They believe that future studies should focus on the interplay between very preterm birth and the wider determinants of socioeconomic inequalities in health.

Source: BMJ-British Medical Journal