Ethnic disparity in severe acute maternal morbidity: a nationwide cohort study in the Netherlands.
BACKGROUND
There are concerns about ethnic disparity in outcome of obstetric health care in high-income countries. Our aim was to assess these differences in a large cohort of women having experienced severe acute maternal morbidity (SAMM) during pregnancy, delivery and puerperium.


METHODS
All women experiencing SAMM were prospectively collected in a nationwide population-based design from August 2004 to August 2006. Women delivering in the same period served as reference cohort. Population-based risks were calculated by ethnicity and by type of morbidity. Additionally, non-Western and Western women having experienced SAMM were compared in multivariable logistic regression analysis.


RESULTS
All 98 Dutch maternity units participated. There were 371 021 deliveries during the study period. A total of 2506 women with SAMM were included, 21.1% of whom were non-Western immigrants. Non-Western immigrants showed a 1.3-fold [95% confidence interval (CI) 1.2-1.5] increased risk to develop SAMM. Large differences were observed among different ethnic minority groups, ranging from a non-increased risk for Moroccan and Turkish women to a 3.5-fold (95% CI 2.8-4.3) increased risk for sub-Saharan African women. Low socio-economic status, unemployment, single household, high parity and prior caesarean were independent explanatory factors for SAMM, although they did not fully explain the differences. Immigration-related characteristics differed by ethnic background.


CONCLUSIONS
Non-Western immigrants have an increased risk of developing SAMM as compared to Western women. Risks varied largely by ethnic origin. Immigration-related characteristics might partly explain the increased risk. The results suggest that there are opportunities for quality improvement by targeting specific disadvantaged groups.
Department of Obstetrics, Leiden University Medical Centre, Leiden, the Netherlands. j.j.zwart@lumc.nl
Joost J
JJ
Zwart
Marina D
MD
Jonkers
Annemiek
A
Richters
Ferko
F
Ory
Kitty W
KW
Bloemenkamp
Johannes J
JJ
Duvekot
Jos
J
van Roosmalen
D000328:Adult; D015331:Cohort Studies; D005006:Ethnicity / Q000706:statistics & numerical data*; D005260:Female; D054625:Healthcare Disparities / Q000208:ethnology*; D006801:Humans; D015994:Incidence; D008428:Maternal Mortality / Q000208:ethnology; D009017:Morbidity; D009426:Netherlands / Q000453:epidemiology; D009773:Obstetric Nursing; D011247:Pregnancy; D011248:Pregnancy Complications / Q000401:mortality*; D011446:Prospective Studies; D012307:Risk Factors; D055815:Young Adult