Social inequalities in the provision of obstetric services in Norway 1967-2009: a population-based cohort study.

Background: Socioeconomic (SE) inequalities have been observed in a number of adverse outcomes of pregnancy and many of the risk factors for such outcomes are associated with a low SE level. However, SE inequalities persist even after adjustment for these risk factors. Less well-off women are more vulnerable, but may also get less adequate health services. The objective of the present study was to assess possible associations between SE conditions in terms of maternal education as well as ethnic background and obstetric care. Methods: A population-based national cohort study from the Medical Birth Registry of Norway. The study population comprised 2 305 780 births from the observation period 1967-2009. Multilevel analysis was used because of the hierarchical structure of the data. Outcome variables included induction of labour, epidural analgesia, caesarean section, neonatal intensive care and perinatal death. Results: While medical interventions in the 1970s were employed less frequently in women of short education and non-western immigrants, this difference was eliminated or even reversed towards the end of the observation period. However, an excess perinatal mortality in both the short-educated [adjusted relative risk (aRR) =2.49] and the non-western immigrant groups (aRR = 1.75) remained and may indicate increasing health problems in these groups. Conclusion: Even though our study suggests a fair and favourable development during the last decades in the distribution across SE groups of obstetric health services, the results suggest that the needs for obstetric care have increased in vulnerable groups, requiring a closer follow-up.