The continuum of maternal morbidity and mortality: Factors associated with severity

doi:10.1016/j.ajog.2004.05.099

American Journal of Obstetrics and Gynecology

Volume 191, Issue 3, September 2004, Pages 939-944

https://doi.org/10.1016/j.ajog.2004.05.099 Get rights and content

Objective

The goal of this study was to examine whether sociodemographic, clinical, and other service-related factors, as well as preventability issues affect a woman's progression along the continuum of morbidity and mortality.

Study design

This was a case-control study of pregnancy-related deaths, women with near-miss morbidity, and those with other severe, but not life threatening, morbidity. Factors associated with maternal outcome were examined.

Results

Provider factors (related to preventability) and clinical diagnosis were significantly associated with progression along the continuum after controlling for sociodemographic characteristics (P < .01 for both associations).

Conclusion

In order to improve mortality rates, we must understand maternal morbidity and how it may lead to death. This study shows that important initiatives include addressing preventability, in particular, provider factors, which may play a role in moving women along the continuum of morbidity and mortality.

Section snippets

Material and methods

This study was conducted at the University of Illinois Medical Center at Chicago (UIMC), a tertiary care and Regionalized Perinatal Network center that coordinates maternal and neonatal services for 10 hospitals. The hospital serves a predominantly African American and Latina population, and has approximately 2200 births per year. A case control design was used to select pregnancy-related deaths, women with near-miss morbidity, and women with other severe, but not life threatening, morbidity

Results

Table I provides a profile of the women in the study according to their location along the morbidity/mortality continuum. The distribution of race/ethnicity, parity, marital status, and insurance status differed within the 3 groups, while there was no difference by age or time of entry into prenatal care. The deaths included higher proportions of African American and Caucasian women compared with the survivors (P < .01), and women who died were also more likely to be multiparous, married, and

Comment

This study examined the relationship of sociodemographic, clinical, and other service-related factors among women at the 3 most severe points on the morbidity/mortality continuum. Similar to other research, there were different distributions of clinical diagnoses among the 3 groups.⁷ The proportion of cardiac, CVA, and embolic diagnoses was higher among the deaths, hemorrhage and infection were higher in the near-miss group, and PIH was higher in the other severe morbidity group. Some

References (9)

C.J. Berg et al.
Pregnancy-related mortality in the United States, 1991-1997
Obstet Gynecol
(2003)
C.J. Berg et al.
Pregnancy-related mortality in the United States, 1987-1990
Obstet Gynecol
(1996)
R.C. Pattinson et al.
Can enquiries into severe acute maternal morbidity act as a surrogate for maternal death enquiries?
BJOG
(2003)
D.D. Rutstein et al.
Measuring the quality of medical care. A clinical method
N Engl J Med
(1976)

There are more references available in the full text version of this article.

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Examination of the Black-White racial disparity in severe maternal morbidity among Georgia deliveries, 2016 to 2020
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Studies find that delivery hospital explains a significant portion of the Black-White gap in severe maternal morbidity. No such studies have focused on the US Southeast, where racial disparities are widest, and few have examined the relative contribution of hospital, residential, and maternal factors.
This study aimed to estimate the portion of Georgia's Black-White gap in severe maternal morbidity during delivery through 42 days postpartum explained by hospital, residential, and maternal factors.
Using linked Georgia hospital discharge, birth, and fetal death records for 2016 through 2020, we identified 413,124 deliveries to non-Hispanic White (229,357; 56%) or Black (183,767; 44%) individuals. We linked hospital data from the American Hospital Association and Center for Medicare and Medicaid Services, and area data from the Area Resource File and American Community Survey. We identified severe maternal morbidity indicator conditions during delivery or subsequent hospitalizations through 42 days postpartum. Using race-specific logistic models followed by a decomposition technique, we estimated the portion of the Black-White severe maternal morbidity gap explained by the following: (1) sociodemographic factors (age, education, marital status, and nativity), (2) medical conditions (diabetes mellitus, gestational diabetes, chronic hypertension, gestational hypertension or preeclampsia, and smoking), (3) obstetrical factors (singleton or multiple, and birth order); (4) access to care (no or third trimester care, and payer), (5) hospital factors that are time-varying (delivery volume, deliveries per full-time equivalent nurse, doctor communication, patient safety, and adverse event composite score) or measured time-invariant characteristics (ownership, profit status, religious affiliation, teaching status, and perinatal level), and (6) residential factors (county urban/rural classification, percent uninsured women of reproductive age, obstetrician-gynecologists per women of reproductive age, number of federally-qualified and community health centers, medically-underserved area [yes/no], and census tract neighborhood deprivation index). We estimated models with and without hospital fixed-effects, which account for unobserved time-invariant hospital characteristics such as within-hospital care processes or unmeasured hospital-specific factors.
There was 1.8 times the rate of severe maternal morbidity per 100 discharges among non-Hispanic Black (3.15) than among White (1.73) individuals, with an explained proportion of 30.4% in models without and 49.8% in models with hospital fixed-effects. In the latter, hospital fixed-effects explained the largest portion of the Black-White severe maternal morbidity gap (15.1%) followed by access to care (14.9%) and sociodemographic factors (14.4%), with residential factors being protective for Black individuals (-7.5%). Smaller proportions were explained by medical (5.6%), obstetrical (4.0%), and time-varying hospital factors (3.2%). Within each category, the largest explanatory portion was payer type (13.3%) for access to care, marital status (10.3%) for sociodemographic, gestational hypertension (3.3%) for medical, birth order (3.6%) for obstetrical, and patient safety indicator (3.1%) for time-varying hospital factors.
Models with hospital fixed-effects explain a greater proportion of Georgia's Black-White severe maternal morbidity gap than models without them, thereby supporting the point that differences in care processes or other unmeasured factors within the same hospital translate into racial differences in severe maternal morbidity during delivery through 42 days postpartum. Research is needed to discern and ameliorate sources of within-hospital differences in care. The substantial proportion of the gap attributable to racial differences in access to care and sociodemographic factors points to other needed policy interventions.
Preconception and perinatal hospitalizations as indicators of risk for severe maternal morbidity in primiparas
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Severe maternal morbidity includes unexpected outcomes of labor and delivery that result in significant short- or long-term consequences to a woman's health. A statewide longitudinally linked database was used to examine hospitalization during and before pregnancy for birthing people with severe maternal morbidity at delivery.
This study aimed to examine the association between hospital visits during pregnancy and 1 to 5 years before pregnancy and severe maternal morbidity at delivery.
This study was a retrospective, population-based cohort analysis of the Massachusetts Pregnancy to Early Life Longitudinal database between January 1, 2004, and December 31, 2018. Nonbirth hospital visits, including emergency department visits, observational stays, and hospital admissions during pregnancy and 5 years before pregnancy, were identified. The diagnoses for hospitalizations were categorized. We compared medical conditions leading to antecedent, nonbirth hospital visits among primiparous birthing individuals with singleton births with and without severe maternal morbidity, excluding transfusions.
Of 235,398 birthing individuals, 2120 had severe maternal morbidity, a rate of 90.1 cases per 10,000 deliveries, and 233,278 did not have severe maternal morbidity. Compared with 4.3% of patients without severe maternal morbidity, 10.4% of patients with severe maternal morbidity were hospitalized during pregnancy. In multivariable analysis, there was a 31% increased risk of hospital admission during the prenatal period, a 60% increased risk of hospital admission in the year before pregnancy, and a 41% increased risk of hospital admission in 2 to 5 years before pregnancy. Compared with 9.8% of non-Hispanic White birthing people, 14.9% of non-Hispanic Black birthing people with severe maternal morbidity experienced a hospital admission during pregnancy. For those with severe maternal morbidity, prenatal hospitalization was most common for those with endocrine (3.6%) or hematologic (3.3%) conditions, with the largest differences between those with and without severe maternal morbidity for musculoskeletal (relative risk, 9.82; 95% confidence interval, 7.06–13.64) and cardiovascular (relative risk, 9.73; 95% confidence interval, 7.26–13.03) conditions.
This study found a strong association between previous nonbirth hospitalizations and the likelihood of severe maternal morbidity at delivery.
Severe maternal morbidity and mortality during the COVID-19 pandemic: a cohort study in Rio de Janeiro
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To identify factors associated with adverse maternal outcomes during the coronavirus disease 2019 (COVID-19) pandemic.
This was a single-centre prospective cohort study at a maternity department in a public general hospital in Rio de Janeiro. All pregnant women evaluated for emergency care, labour and delivery, respiratory symptoms, obstetric reasons or medical reasons between May 2020 and March 2022 at the study institution were invited to enrol in this study. The endpoint was maternal mortality or intensive care unit (ICU) admission.
In total, 1609 pregnant women were enrolled in this study. Of these, 25.5% (n=410) were infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) based on reverse transcription polymerase chain reaction or an antigen test. There were 21 deaths and 67 ICU admissions in 4% of the cohort. The incidence of severe maternal morbidity and mortality was higher during the Gamma wave than during the Delta wave (P=0.003). Vaccination conferred protection against the endpoint [relative risk (RR) 0.4, 95% confidence interval (CI) 0.1–0.9; P=0.0169]. Factors associated with severe morbidity and mortality included caesarean section (RR 3.7, 95% CI 1.7–7.9; P=0.0008), SARS-CoV-2 infection in the third trimester (RR 2.4, 95% CI 1.1–5.6; P=0.0006) and comorbidities (RR 3, 95% CI 1.8–5.2; P<0.0001).
COVID-19 was significantly associated with the risk of severe maternal morbidity and mortality. Immunization of pregnant women against COVID-19 was highly protective against adverse outcomes, and should be encouraged during pregnancy.
Antenatal anaesthetic assessment of obstetric patients
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Early identification and anaesthetic assessment of high-risk patients in pregnancy is important and best delivered through a formal assessment clinic. It provides the opportunity to provide information, agree management plans, and carry out necessary investigations and referrals to other specialists prior to labour and delivery. Clear referral criteria and lines of communication are necessary for an effective service.
Severe Maternal Morbidity and Maternal Mortality in Women With Intellectual and Developmental Disabilities
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Despite increased attention on severe maternal morbidity and maternal mortality, scant research exists on adverse maternal outcomes in women with disabilities. This study compares the rates of severe maternal morbidity and maternal mortality in women with and without intellectual and developmental disabilities.
This study used 2004–2017 Healthcare Cost and Utilization Project Nationwide Inpatient Sample data. Analyses were conducted in 2019‒2020. The risk of severe maternal morbidity with and without blood transfusion and maternal mortality during delivery among women with and without intellectual and developmental disabilities were compared using modified Poisson regression analysis.
This study identified 32,324 deliveries to women with intellectual and developmental disabilities. Per 10,000 deliveries, 566 deliveries with severe maternal morbidity occurred in women with intellectual and developmental disabilities compared with 239 in women without intellectual and developmental disabilities. Women with intellectual and developmental disabilities had greater risk of both severe maternal morbidity (risk ratio=2.36, 95% CI=2.06, 2.69) and nontransfusion severe maternal morbidity (risk ratio=2.95, 95% CI=2.42, 3.61) in unadjusted analyses, which was mitigated in adjusted analyses for sociodemographic characteristics (risk ratio=1.74, 95% CI=1.47, 2.06; risk ratio=1.85, 95% CI=1.42, 2.41) and the expanded obstetric comorbidity index (risk ratio=1.23, 95% CI=1.04, 1.44; risk ratio=1.31, 95% CI=1.02, 1.68). The unadjusted incidence of maternal mortality in women with intellectual and developmental disabilities was 284 per 100,000 deliveries, nearly 4-fold higher than in women without intellectual and developmental disabilities (69 per 100,000 deliveries; risk ratio=4.07, 95% CI=2.04, 8.12), and the risk remained almost 3-fold higher after adjustment for sociodemographic characteristics (risk ratio=2.86, 95% CI=1.30, 6.29) and the expanded obstetric comorbidity index (risk ratio=2.30, 95% CI=1.05, 5.29).
Women with intellectual and developmental disabilities are at increased risk of severe maternal morbidity and maternal mortality. These findings underscore the need for enhanced monitoring of the needs and maternal outcomes of women with intellectual and developmental disabilities in efforts to improve maternal health.
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View all citing articles on Scopus

: Presented at the Twenty-Fourth Annual Meeting of the Society for Maternal Fetal Medicine, February 2-7, 2004, New Orleans, La.

: Funding from the Centers for Disease Control and Prevention and the Association of Schools of Public Health “Investigation of Factors Associated with Maternal Mortality” (S1069/19-20).

View full text

Transactions of the Twenty-Fourth Annual Meeting of the Society for Maternal-Fetal MedicineThe continuum of maternal morbidity and mortality: Factors associated with severity

Objective

Study design

Results

Conclusion

Section snippets

Material and methods

Results

Comment

Obstet Gynecol

Obstet Gynecol

BJOG

Measuring the quality of medical care. A clinical method

N Engl J Med

Transactions of the Twenty-Fourth Annual Meeting of the Society for Maternal-Fetal Medicine
The continuum of maternal morbidity and mortality: Factors associated with severity