The influence of ethnicity on the outcomes of violence in pregnancy

Abstract

Aim. To investigate the influence of ethnicity on immediate and long-term (five years post-partum) foetal, maternal and injury-related outcomes.

Methods. A retrospective, population-based study analysing maternal discharge records linked to birth/death certificates for women aged 25 years and under. Discharge records were grouped according to ethnicity (Maori and non-Maori) and as follows: (1) a pregnancy-related hospital admission, but no associated or subsequent assault recorded (pregnant only); (2) an assault-related hospital admission event after the pregnancy, but within five years of the index pregnancy (assault after pregnancy); and (3) an assault recorded within the same hospital admission event as the pregnancy (assault during pregnancy). Generalised linear models for the binomial family were conducted to explore increased risk ratios of pregnancy-related and subsequent injury outcomes depending on ethnicity and group assignment.

Results. Compared with the pregnancy-only group, rate ratios (RRs) for maternal and foetal outcomes were higher in the assault after pregnancy group and the assault during pregnancy group. For injury outcomes in the five years after the injury event, RRs for the assault after pregnancy group exceeded both the pregnancy-only and the assault during pregnancy groups. RRs for non-Maori women assaulted after pregnancy were higher for injury hospitalisations, fracture and intracranial injury than those for Maori women.

Conclusion. Given that Maori women experience a higher prevalence of severe intimate partner violence and more difficulties accessing health care, we suggest that the findings highlight potential problems for health care access for Maori women experiencing violence.

Keywords:

• violence against women
• ethnicity
• health care access

Acknowledgements

The authors extend their gratitude to Professor Tracey MacIntosh. Without Professor McIntosh's insightful comments, this paper would not have been possible. We also acknowledge the valuable input of Chris Lewis, Ministry of Health and the Ethnicity and Health reviewers for constructive comments on an earlier draft of this paper.

Key messages

1. We investigated the influence of ethnicity on immediate and long-term (five years post-partum) foetal, maternal and injury-related outcomes for New Zealand women aged 25 years and under.

2. Rate ratios for non-Maori women assaulted after pregnancy were higher for injury hospitalisations, fracture and intracranial injury than those for Maori women, who are the indigenous population of New Zealand. This is despite a higher prevalence of Maori women experiencing IPV than non-Maori women and a higher proportion of Maori women reporting more severe violence.

3. The use of physical injury resulting in hospitalisation as an outcome measure in this investigation is based on the assumption of equal access across ethnic groups. However, evidence exists that Maori may be less likely to seek medical help or face more barriers to accessing services than other New Zealanders.

4. We suggest that these findings highlight potential problems for health care access for Maori women experiencing IPV.

5. It is possible that the results may not be generalisable to the total population of women who have given birth in New Zealand between 2001 and 2006. Indeed, the social determinants of health for both Maori and non-Maori women who choose to delay childbirth until they are older than 25 years may be quite different from that of young mothers.

Notes

1. Outcomes that could not be investigated because of sufficient numbers include: death; placental abruption; uterine rupture; spontaneous abortion; dislocation, sprain or strain; nerve damage; injury to the blood vessel; injury to internal organs; and burns.