In the UK, black Caribbean and black African women have twice as much risk of experiencing severe pregnancy complications than white women, according to research published today on BMJ.com.
The study, the first of its kind undertaken in the UK, also found that Pakistani women have a significantly higher risk of severe pregnancy-related health problems than white women. Today's research reflects previous studies carried out in the US, Canada and the Netherlands.
Using the UK Obstetric Surveillance System (UKOSS), Dr Marian Knight from the University of Oxford and her team, investigated 686 cases of severe pregnancy-related complications out of a total of 775,186 maternities between February 2005 and February 2006. Complications included hysterectomy after childbirth, fits with high blood pressure (eclampsia) or blood clots in the lungs (pulmonary embolism).
Dr Knight's research concludes that non-white women are one and half times more at risk of experiencing severe pregnancy-related complications than white women. This risk doubles for black Caribbean and black African women.
There is an overall estimated risk of severe complications of 89 cases per 100,000 maternities. The authors conclude that for white women this risk is around 80 cases per 100,000 maternities, 126 cases for non-white women as a whole, 188 cases for black African woman and 196 for black Caribbean women.
Knight argues that the increased risk for non-white women may be because of pre-existing medical factors or because of care during pregnancy, labour and birth and is unlikely to be due to the socio-economic situation of the woman or whether she smoked or was obese. She says the research "highlights to clinicians and policy-makers the importance of tailored maternity services and improved access to care for ethnic minority women".
The authors believe that one possible reason for the higher risk of complications is access to care. A number of studies have previously indicated that this was a contributing factor to ethnic differences in health. A recent national survey of women's experience of maternity care in the UK reported that women from black and minority ethnic groups were more likely to recognise their pregnancy later, access care later and as a result book antenatal care later than white women. These women also said they did not feel they were treated with respect and talked to in a way they understood by staff during pregnancy, labour and birth and postnatal care.
In an accompanying editorial, Wendy Pollock from the University of Melbourne believes that routine collection of more detailed data is key to improving knowledge. She says that one unresolved question is whether ethnicity itself is directly relevant to poor maternal outcomes, or whether it is a surrogate marker for other factors like low socioeconomic status, low level of education and poor nutrition. Ethnicity is a "blunt marker when each ethnic grouping is so diverse," she argues.
Pollock also makes the point that more resources need to be directed to raising awareness about the dangers of delaying childbearing beyond the age of 35 years.
She says: "The additional burden placed on the health of these women needs further investigation because women over 40 are up to eight times more likely to have a pregnancy related death than those in their early 20s. For this group of women, improving access to maternity services is not the solution. However, defining and communicating the risk of delaying childbirth for society may speed policy movements that could support earlier childbearing, such as paid maternity leave and flexible arrangements for return to work."