Abstract
This study examines the incidence of homicide as the cause of mortality in women who are pregnant or post partum in Louisiana in 2016 through 2017, comparing this with other causes of maternal mortality.
Maternal mortality in the United States is on the rise,1 mobilizing programmatic and policy responses at local, state, and federal levels. A growing number of jurisdictions identify homicide as a leading cause of death during pregnancy and the postpartum period, yet relative to the attention paid to obstetric causes of death, rigorous examination of mortality from nonobstetric causes during pregnancy and the postpartum period is rare, particularly in comparison with similar investigations of women who were not pregnant.
Methods
Via data provided by the Louisiana Department of Health, we conducted a retrospective analysis of all verified cases of maternal death (death during pregnancy or up to 1 year post partum) occurring in Louisiana from January 2016 through December 2017. Verification involved the linkage of a death record with a live birth or fetal death record issued within 1 year of the date of death and/or an additional review of pregnancy data checkboxes indicating the decedent died during pregnancy (prior to a live birth or fetal death). We grouped deaths by International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes for the underlying cause of death on the death record and calculated 2-year mortality ratios per 100 000 live births. Data on the number of homicides among women and girls of reproductive age in Louisiana from 2016 through 2017 were extracted from the US Centers for Disease Control and Prevention’s Wide-Ranging Online Data for Epidemiologic Research database2 and used to calculate corresponding 2-year homicide rates among women and girls who were neither pregnant nor post partum, for comparison. This study was approved by the Tulane University institutional review board. All data analyzed in this study were deidentified and therefore exempt from informed consent procedures.
We estimated age-stratified homicide rates, rate ratios, and 95% CIs comparing homicide incidence between women and girls who were vs were not pregnant or post partum to identify associations between pregnancy and the risk of violent death. Two-sided P values less than .05 were considered significant. Analyses were conducted in SAS version 9.3 (SAS Institute), and data analysis occurred from June 2018 to July 2018.
Results
Of the 119 pregnancy-associated deaths in Louisiana from January 2016 through December 2017, 13.4% were homicides (n = 16). Homicide mortality (12.9 [95% CI, 7.9-21.0] deaths per 100 000 live births) exceeded mortality from any single cause of obstetric cause of death or groups of common obstetric causes, including hypertensive disorders (3.2 [95% CI, 1.2-8.6] deaths per 100 000 live births) and obstetric embolism (4.8 [95% CI, 2.2-10.8] deaths per 100 000 live births; Table 1). The risk of homicide was 2-fold higher among women and girls who were pregnant or post partum compared with women and girls who were not (rate ratio, 2.04 [95% CI, 1.23-3.42]) and particularly elevated among young women and girls (aged 10-29 years) who were pregnant or post partum (16.2 [95% CI, 9.4-27.8] deaths per 100 000 live births; rate ratio, 2.38 [95% CI, 1.3-4.3]; Table 2).
Table 1. Two-Year Pregnancy-Associated Mortality Ratios by Cause of Death in Louisiana (2016-2017).
| Cause of Death | Deaths per 100 000 Live Births (95% CI)a |
|---|---|
| Pregnancy-associated causes | |
| Hypertensive disorders in pregnancy, childbirth, and the puerperium | 3.2 (1.2-8.6) |
| Obstetric embolism | 4.8 (2.2-10.8) |
| Death from any obstetric cause occurring more than 42 d but less than 1 y after deliveryb | 4.8 (2.2-10.8) |
| Other maternal diseases complicating pregnancy, childbirth, and the puerperiumc | 8.1 (4.3-15.0) |
| Other pregnancy-associated complicationsd | 20.9 (14.3-30.7) |
| Natural diseasese | 13.7 (8.5-22.0) |
| Homicide | 12.9 (7.9-21.0) |
| Motor vehicle crashes | 10.5 (6.1-18.1) |
| Other unintentional injuries | 11.3 (6.7-19.0) |
| Suicide | 2.4 (0.8-7.5) |
| Other external causes | 1.6 (0.4-6.4) |
Abbreviation: ICD-10, International Statistical Classification of Diseases and Related Health Problems, Tenth Revision.
The 95% CIs were estimated using a Poisson distribution.
ICD-10 code O96.
ICD-10 code O99.
Includes complications of the puerperium not elsewhere classified (ICD-10 code O90), other maternal disorders predominantly related to pregnancy (ICD-10 code O22-O29), premature rupture of membranes (ICD-10 code O42), and complications of labor and delivery (ICD-10 code O75).
Includes cancer; HIV; endocrine, nutritional, and metabolic diseases of the nervous system; diseases of the circulatory system; and diseases of the respiratory system.
Table 2. Homicides per 100 000 Population by Pregnancy Status and Age and Associations Between Pregnancy Status and Homicide in Louisiana (2016-2017)a.
| Finding | Age Group, y | Total | |
|---|---|---|---|
| 10-29 | 30-54 | ||
| Homicide deaths among women and girls who were pregnant or post partum per 100 000 live births (95% CI) | 16.2 (9.4-27.8) | 6.9 (2.21-21.3) | 12.9 (7.9-21.0) |
| Homicide deaths per 100 000 women and girls who were nonpregnant and non–post partum (95% CI)b | 6.8 (5.4-8.43) | 5.9 (4.8-7.3) | 6.3 (5.4-7.33) |
| Homicide rate ratio (95% CI) | 2.38 (1.3-4.3) | 1.16 (0.4-3.7) | 2.04 (1.23-3.42) |
The 95% CIs were estimated using a Poisson distribution.
The population was the total number of women and girls in Louisiana aged 10 to 54 years minus the number of live births.
Discussion
Our statewide analysis of maternal deaths from 2016 through 2017 revealed 2 salient findings. First, homicide is a leading cause of maternal death in Louisiana. Incidence of homicide during pregnancy and the postpartum period was greater than any single obstetric cause of death. Our estimated rate is among the highest reported across a growing number of jurisdictions,3 possibly due in part to improved case ascertainment through the use of linked and verified data and/or reflecting a truly higher incidence within Louisiana, given the state’s consistently high incidence of homicide among women and girls.4
Second, we found that pregnancy and the postpartum period are times of increased risk for homicide among women and girls of reproductive age. Although the evidence remains scant,3 the profound implications for the potential of an association between pregnancy status and homicide warrant action on the part of researchers, health care professionals, and policy makers. Health care professionals’ encounters with women and girls during pregnancy and the postpartum period—times when they are most likely to seek health care services—represent critical windows of opportunity for violence prevention services and interventions targeting them, their partners, or their families.
Our limitations include classification of cause of death based solely on death-record ICD-10 codes. This is not equivalent to a full maternal mortality review board process, which may include multiple data sources (medical records, autopsy reports, and discharge reports) and final classification based on temporal and causal associations between clinical factors associated with the pregnancy and death. Furthermore, vital records alone lack potentially important information necessary to fully characterize and contextualize pregnancy-associated homicide cases and identify targetable risk factors, including the victim-perpetrator relationship and features of the social and physical environment in which the incident occurred.
The growing establishment of state maternal mortality review committees is an important step toward reversing its increasing incidence.5 Such committees, which are charged with making recommendations and promoting effective activities to prevent maternal death at the individual, clinical, facility, and systems levels,5 should begin to identify and address homicide with the same imperative and rigor given to obstetrically caused deaths, despite the associated challenges in reviewing these cases. An effort to do so is underway in Illinois, for example.6 Failure to engage in these efforts nationwide will perpetuate preventable loss of life among women and girls in the United States who are pregnant or in the postpartum period.
References
- 1.MacDorman MF, Declercq E, Cabral H, Morton C. Recent increases in the U.S. maternal mortality rate: disentangling trends from measurement issues. Obstet Gynecol. 2016;128(3):447-455. doi: 10.1097/AOG.0000000000001556 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.US Department of Health and Human Services, US Centers for Disease Control and Prevention About natality, 2007-2018. https://wonder.cdc.gov/natality-current.html. Published 2018. Accessed December 16, 2019.
- 3.Koch AR, Rosenberg D, Geller SE; Illinois Department of Public Health Maternal Mortality Review Committee Working Group . Higher risk of homicide among pregnant and postpartum females aged 10-29 years in Illinois, 2002-2011. Obstet Gynecol. 2016;128(3):440-446. doi: 10.1097/AOG.0000000000001559 [DOI] [PubMed] [Google Scholar]
- 4.Violence Policy Center Female homicide victimization by males. http://vpc.org/revealing-the-impacts-of-gun-violence/female-homicide-victimization-by-males/. Published 2017. Accessed December 16, 2019.
- 5.US Centers for Disease Control and Prevention Building US capacity to review and prevent maternal deaths: report from maternal mortality review committees, a view into their critical role. https://www.cdcfoundation.org/sites/default/files/upload/pdf/MMRIAReport.pdf. Published 2018. Accessed December 16, 2019.
- 6.Koch AR, Geller SE. Addressing maternal deaths due to violence: the Illinois experience. Am J Obstet Gynecol. 2017;217(5):556.e1-556.e6. doi: 10.1016/j.ajog.2017.08.005 [DOI] [PubMed] [Google Scholar]