Severe maternal morbidity in Canada, 1991-2001.
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ABSTRACT: Background
Although death rates are often used to monitor the quality of health care, in industrialized countries maternal deaths have become rare. Severe maternal morbidity has therefore been proposed as a supplementary indicator for surveillance of the quality of maternity care. Our purpose in this study was to describe severe maternal morbidity in Canada over a 10-year period, among women with or without major pre-existing conditions.Methods
We carried out a retrospective cohort study of severe maternal morbidity involving 2,548,824 women who gave birth in Canadian hospitals between 1991 and 2000. Thirteen conditions that may threaten the life of the mother (e.g., eclampsia) and 11 major pre-existing chronic conditions (e.g., diabetes) that could be identified from diagnostic codes were noted.Results
The overall rate of severe maternal morbidity was 4.38 per 1000 deliveries. The fatality rate among these women was 158 times that of the entire sample. Rates of venous thromboembolism, uterine rupture, adult respiratory distress syndrome, pulmonary edema, myocardial infarction, severe postpartum hemorrhage requiring hysterectomy, and assisted ventilation increased substantially from 1991 to 2000. The presence of major pre-existing conditions increased the risk of severe maternal morbidity to 6-fold.Interpretation
Severe maternal morbidity occurs in about 1 of 250 deliveries in Canada, with marked recent increases in certain morbid conditions such as pulmonary edema, myocardial infarction, hemorrhage requiring hysterectomy, and the use of assisted ventilation.
SUBMITTER: Wen SW
PROVIDER: S-EPMC1216316 | biostudies-literature | 2005 Sep
REPOSITORIES: biostudies-literature
Publications
Severe maternal morbidity in Canada, 1991-2001.
Wen Shi Wu SW Huang Ling L Liston Robert R Heaman Maureen M Baskett Tom T Rusen I D ID Joseph K S KS Kramer Michael S MS
CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne 20050901 7
<h4>Background</h4>Although death rates are often used to monitor the quality of health care, in industrialized countries maternal deaths have become rare. Severe maternal morbidity has therefore been proposed as a supplementary indicator for surveillance of the quality of maternity care. Our purpose in this study was to describe severe maternal morbidity in Canada over a 10-year period, among women with or without major pre-existing conditions.<h4>Methods</h4>We carried out a retrospective coho ...[more]
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Project description:ImportanceOver the past 2 decades, there has been a trend toward increasing maternal age in many high-income countries. Maternal age may lead to greater attendant morbidity and mortality for Canadian mothers.ObjectiveTo investigate the association of maternal age, adjusting for patient-level and hospital-level factors, with severe maternal morbidity (SMM) and maternal death in Canada.Design, setting, and participantsA nationwide population-based cohort study of all antepartum, peripartum, and postpartum women and adolescents seen at Canadian acute care hospitals from April 1, 2004, to March 31, 2015. All analyses were completed on September 13, 2018.ExposuresMaternal age at the index delivery.Main outcomes and measuresSevere maternal morbidity and maternal death during pregnancy and within 6 weeks after termination of pregnancy.ResultsDuring the study period, there were 3?162?303 new pregnancies (mean [SD] maternal age, 29.5 [5.6] years) and 3?533?259 related hospital admissions. There were 54?219 episodes of SMM (17.7 cases per 1000 deliveries) in the entire study period, with a 9.8% relative increase from 2004-2005 to 2014-2015, in addition to an increasing proportion of pregnancies to older mothers. Independent patient-level factors associated with SMM included increasing Maternal Comorbidity Index; maternal age 19 years or younger and 30 years or older, with the greatest risk experienced by women 45 years or older (odds ratio [OR], 2.69; 95% CI, 2.34-3.06 compared with maternal age 20-24 years); and lowest income quintile (OR, 1.19; 95% CI, 1.14-1.22 compared with highest income quintile). Hospital-level factors associated with SMM included specific provinces. Independent patient-level factors associated with maternal mortality included increasing Maternal Comorbidity Index, age 40 to 44 years (OR, 3.39; 95% CI, 1.68-6.82 compared with age 20-24 years), age 45 years or older (OR, 4.39; 95% CI, 1.01-19.10 compared with age 20-24 years), and lowest income quintile (OR, 4.14; 95% CI, 2.03-8.50 compared with highest income quintile). Hospital-level factors associated with maternal mortality included lowest hospital pregnancy volume.Conclusions and relevanceIn Canada, maternal age and SMM have increased over the past decade. Results of this study suggest that province of residence, maternal comorbidity, residence income quintile, and extremes of maternal age, especially those 45 years or older, were associated with SMM and mortality. These findings are relevant to prospective parents, their health care team, and public health planning.
| S-EPMC6714030 | biostudies-literature
Project description:ImportanceSevere maternal morbidity is defined by potentially life-threatening conditions. The association between the number of severe maternal morbidity (SMM) indicators and maternal death is not known.ObjectiveTo quantify the association between the number of SMM indicators and maternal mortality.Design, setting, and participantsThis population-based cohort study used provincial databases for data on all live birth and stillbirth hospital deliveries among women in Ontario, Canada, from April 1, 2002, to February 18, 2017. Excluded from this cohort were those with invalid identification number, non-Ontario residency, maternal age younger than 10 years or older than 55 years or unknown, or gestational age fewer than 20 weeks or unknown as well as any out-of-hospital births, ectopic pregnancies, or spontaneous or induced abortions.ExposuresNumber of SMM indicators identified between 20 weeks' gestation and 42 days after the index delivery.Main outcomes and measuresMaternal death occurring from delivery to 42 days after the index delivery.ResultsOf the 1?953?943 total births among 1?211?396 women, 181 maternal deaths occurred within 42 days after birth, a rate of 9.3 per 100?000 births. Of the 181 women who died, 123 (68.0%) had at least 1 SMM indicator compared with 1.7% (33?152) of women who survived. Standardized differences suggested that women who died, compared with the women who lived, were older (mean [SD] age, 31.0 [6.2] years vs 30.1 [5.5] years; standardized difference, 0.15) and more likely to reside in a lower-income area (99 [54.7%] vs 832?231 [42.6%]; standardized difference, 0.24), be nulliparous (93 [51.4%] vs 880?386 [45.1%]; standardized difference, 0.13), and be of Afro-Caribbean origin (12 [6.6%] vs 64?948 [3.3%]; standardized difference, 0.15). The most frequent SMM indicators were intensive care unit admission (81 [44.8%]), invasive ventilation (77 [42.5%]), cardiac conditions (69 [38.1%]), complications of obstetric surgery or procedures (32 [17.7%]), and postpartum hemorrhage with blood transfusion (31 [17.1%]). The rate of maternal mortality increased exponentially with the number of SMM indicators: 0 indicators (3.0 per 100?000 births), 1 (71.7 per 100?000 births), 2 (385.9 per 100?000 births), 3 (1274.2 per 100?000 births), 4 (2236.8 per 100?000 births), 5 (4285.7 per 100?000 births), and 6 or more (9422.5 per 100?000 births). Adjusted relative risks for maternal death ranged from 20.1 (95% CI, 11.6-34.7) with 1 SMM indicator to 2192.0 (95% CI, 1287.0-3735.0) with 6 or more SMM indicators compared with 0 indicators.Conclusions and relevanceMaternal death may be associated with the number of SMM indicators and occur in certain identifiable groups of women; targeting preventable SMM indicators or limiting their progression may reduce the number of maternal deaths.
| S-EPMC6324398 | biostudies-literature
Project description:ImportanceSevere maternal morbidity and mortality are important indicators of maternal health. Pregnancy rates are increasing in women with disabilities, but their risk of severe maternal morbidity and mortality is unknown, despite their significant social and health disparities.ObjectiveTo determine the risk of severe maternal morbidity or mortality among women with a physical, sensory, or intellectual/developmental disability compared with women without disabilities.Design, setting, and participantsThis population-based cohort study used linked health administrative data in Ontario, Canada, from 2003 to 2018. The cohort included all singleton births to women with preexisting physical, sensory, and intellectual/developmental disabilities as well as with 2 disabilities or more compared with women without a disability. Data analysis was conducted from September 2019 to September 2020.ExposuresDisabilities were identified with published algorithms applied to diagnoses in 2 physician visits or more or at least 1 emergency department visit or hospitalization.Main outcomes and measuresSevere maternal morbidity (a validated composite of 40 diagnostic and procedural indicators) or all-cause maternal mortality, arising between conception and 42 days post partum. Relative risks were adjusted for maternal age, parity, income quintile, rurality, chronic medical conditions, mental illness, and substance use disorders.ResultsThe cohort comprised women with physical disabilities (144 972 women; mean [SD] age, 29.8 [5.6] years), sensory disabilities (45 259 women; mean [SD] age, 29.1 [6.0] years), intellectual/developmental disabilities (2227 women; mean [SD] age, 26.1 [6.4] years), and 2 or more disabilities (8883 women; mean [SD] age, 29.1 [6.1] years), and those without disabilities (1 601 363 women; mean [SD] age, 29.6 [5.4] years). The rate of severe maternal morbidity or death was 1.7% (27 242 women) in women without a disability. Compared with these women, the risk of severe maternal morbidity or death was higher in women with a physical disability (adjusted relative risk [aRR], 1.29; 95% CI, 1.25-1.34), a sensory disability (aRR, 1.14; 95% CI, 1.06-1.21), an intellectual/developmental disability (aRR, 1.57; 95% CI, 1.23-2.01), and 2 or more disabilities (aRR, 1.74; 95% CI, 1.55-1.95). Similar aRRs were observed for severe maternal morbidity or death arising in pregnancy, from birth to 42 days post partum, and from 43 to 365 days post partum. Women with disabilities were more likely than those without disabilities to experience multiple severe maternal morbidity indicators. The most prevalent indicators in all groups were intensive care unit admission, severe postpartum hemorrhage, puerperal sepsis, and severe preeclampsia.Conclusions and relevanceIn this study, women with a preexisting disability were more likely to experience severe maternal morbidity or mortality. Preconception and perinatal care provisions should be considered among women with a disability to mitigate the risk of these rare but serious outcomes.
| S-EPMC7871190 | biostudies-literature
Project description:ImportanceEmergency department (ED) use during pregnancy may be associated with worse obstetrical outcomes, possibly because of differences in access to health care. It is not known whether ED use before pregnancy is associated with serious adverse maternal and perinatal outcomes.ObjectiveTo study the association between prepregnancy ED use and adverse maternal and perinatal outcomes.Design, setting, and participantsThis population-based cohort study was conducted in Ontario, Canada, and included all livebirths and stillbirths from April 2003 to January 2020.ExposuresMain exposure was any ED encounter within 90 days preceding the start of the index pregnancy.Main outcomes and measuresPrimary outcome was a composite of severe maternal morbidity (SMM) from 20 weeks' gestation to 42 days' post partum. Secondary outcomes included severe neonatal morbidity (SNM) from 0 to 27 days, neonatal death, and stillbirth. Relative risks (RRs) were adjusted for maternal age, income, and rurality.ResultsOf 2 130 245 births, there were 2 119 335 livebirths (99.5%) and 10 910 stillbirths (0.5%). The mean (SD) maternal age was 29.6 (5.4) years, 212 478 (9.9%) were rural dwelling, and 498 219 (23%) had 3 or more comorbidities. Among all births, 218 011 (9.7%) had a prepregnancy ED visit. The rate of SMM was higher among women with a prepregnancy ED visit than those without (22.3 vs 16.5 per 1000 births), with an RR of 1.34 (95% CI, 1.30-1.38) and an adjusted RR (aRR) of 1.37 (95% CI, 1.33-1.42). Compared with no prepregnancy ED visit, the aRR was higher in those with 1 (1.29; 95% CI, 1.24-1.34), 2 (1.51; 95% CI, 1.42-1.61), and 3 or more (1.74; 95% CI, 1.61-1.90) ED visits. Prepregnancy ED visits for a hematological (aRR, 13.60; 95% CI, 10.48-17.64), endocrine (aRR, 4.96; 95% CI, 3.72-6.62), and circulatory (aRR, 2.27; 95% CI, 1.68-3.07) conditions were associated with the highest aRRs for SMM. The rate of SNM was higher among newborns whose mother visited the ED within 90 days before pregnancy (68.2 vs 55.4 per 1000 births; aRR, 1.24; 95% CI, 1.22-1.26) as was the risk of neonatal death (aRR, 1.26; 95% CI, 1.16-1.37) and stillbirth (aRR, 1.18; 95% CI, 1.11-1.25).Conclusions and relevanceIn this study, ED use was common before pregnancy. These findings suggest that ED use may not only reflect a woman's access to prepregnancy care but also higher future risk of severe maternal and perinatal morbidity, potentially offering a useful trigger for health system interventions to decrease adverse pregnancy outcomes.
| S-EPMC9440393 | biostudies-literature
Project description:ObjectiveTo evaluate the associations between the number of chronic conditions and maternal race and ethnicity (race) with the risk of severe maternal morbidity.MethodsUsing the National Inpatient Sample, Healthcare Cost and Utilization Project, Agency for Healthcare Research and Quality, years 2016-2017, we examined risk of severe maternal morbidity among 1,480,925 delivery hospitalizations among women of different races and with different numbers of comorbid conditions using multivariable logistic regression.ResultsThe rate of severe maternal morbidity was 139.7 per 10,000 deliveries. Compared with women with no comorbidities (rate 48.5/10,000), there was increased risk of severe maternal morbidity among women with one comorbidity (rate 238.6; odds ratio [OR] 5.0, 95% CI 4.8-5.2), two comorbidities (rate 379.9; OR 8.1, 95% CI 7.8-8.5), or three or more comorbidities (rate 560; OR 12.1, 95% CI 11.5-12.7). In multivariable regressions, similar associations were noted for women with one (adjusted odds ratio [aOR] 4.4, 95% CI 4.2-4.6), two (aOR 6.6, 95% CI 6.3-6.9), or three or more comorbidities (aOR 9.1, 95% CI 8.7-9.6). Black women had higher rates of comorbid conditions than all other racial and ethnic groups, with 55% (95% CI 54-56%) of Black women having no comorbidities, compared with 67% (95% CI 67-68%) of White women, 68% (95% CI 67-69%) of Hispanic women, and 72% (95% CI 71-73%) of Asian women.ConclusionWe found a dose-response relationship between number of comorbidities and risk of severe maternal morbidity, with the highest rates of severe maternal morbidity among women with three or more comorbidities. Focusing on the prevention and treatment of chronic conditions among women of childbearing age may have the potential to improve maternal outcomes across races and ethnicities.
| S-EPMC8006182 | biostudies-literature
Project description:ObjectiveSignificant changes to the delivery of obstetrical care that occurred with the onset of the COVID-19 pandemic may be associated with higher risks of adverse maternal outcomes. We evaluated preeclampsia/HELLP (hemolysis, elevated liver enzymes and low platelets) syndrome and composite severe maternal morbidity (SMM) among pregnant people who gave birth during the COVID-19 pandemic and compared these data with those of people who gave birth before the pandemic in Ontario, Canada.MethodsThis was a population-based, retrospective cohort study using linked administrative data sets from ICES. Data on pregnant people at ≥20 weeks gestation who gave birth between March 15, 2020, and September 30, 2021, were compared with those of pregnant people who gave birth within the same date range for the years 2015-2019. We used multivariable logistic regression to assess the effect of the pandemic period on the odds of preeclampsia/HELLP syndrome and composite SMM, adjusting for maternal baseline characteristics and comorbidities.ResultsThere were no differences between the study periods in the adjusted odds ratios (aORs) for preeclampsia/HELLP syndrome among primiparous (aOR 1.00; 95% CI 0.91-1.11) and multiparous (aOR 0.94; 95% CI 0.81-1.09) patients and no differences for composite SMM (primiparous, aOR 1.00; 95% CI 0.95-1.05; multiparous, aOR 1.01; 95% CI 0.95-1.08).ConclusionAdverse maternal outcomes were not higher among pregnant people who gave birth during the first 18 months of the COVID-19 pandemic in Ontario, Canada, when compared with those who gave birth before the pandemic.
| S-EPMC8979839 | biostudies-literature
Project description:ImportanceEvidence indicates that immigrant women and women residing within low-income neighborhoods experience higher adversity during pregnancy. Little is known about the comparative risk of severe maternal morbidity or mortality (SMM-M) among immigrant vs nonimmigrant women living in low-income areas.ObjectiveTo compare the risk of SMM-M between immigrant and nonimmigrant women residing exclusively within low-income neighborhoods in Ontario, Canada.Design, setting, and participantsThis population-based cohort study used administrative data for Ontario, Canada, from April 1, 2002, to December 31, 2019. Included were all 414 337 hospital-based singleton live births and stillbirths occurring between 20 and 42 weeks' gestation, solely among women residing in an urban neighborhood of the lowest income quintile; all women were receiving universal health care insurance. Statistical analysis was performed from December 2021 to March 2022.ExposuresNonrefugee immigrant status vs nonimmigrant status.Main outcomes and measuresThe primary outcome, SMM-M, was a composite outcome of potentially life-threatening complications or mortality occurring within 42 days of the index birth hospitalization. A secondary outcome was SMM severity, approximated by the number of SMM indicators (0, 1, 2 or ≥3 indicators). Relative risks (RRs), absolute risk differences (ARDs), and odds ratios (ORs) were adjusted for maternal age and parity.ResultsThe cohort included 148 085 births to immigrant women (mean [SD] age at index birth, 30.6 [5.2] years) and 266 252 births to nonimmigrant women (mean [SD] age at index birth, 27.9 [5.9] years). Most immigrant women originated from South Asia (52 447 [35.4%]) and the East Asia and Pacific (35 280 [23.8%]) regions. The most frequent SMM indicators were postpartum hemorrhage with red blood cell transfusion, intensive care unit admission, and puerperal sepsis. The rate of SMM-M was lower among immigrant women (2459 of 148 085 [16.6 per 1000 births]) than nonimmigrant women (4563 of 266 252 [17.1 per 1000 births]), equivalent to an adjusted RR of 0.92 (95% CI, 0.88-0.97) and an adjusted ARD of -1.5 per 1000 births (95% CI, -2.3 to -0.7). Comparing immigrant vs nonimmigrant women, the adjusted OR of having 1 SMM indicator was 0.92 (95% CI, 0.87-0.98), the adjusted OR of having 2 indicators was 0.86 (95% CI, 0.76-0.98), and the adjusted OR of having 3 or more indicators was 1.02 (95% CI, 0.87-1.19).Conclusions and relevanceThis study suggests that, among universally insured women residing in low-income urban areas, immigrant women have a slightly lower associated risk of SMM-M than their nonimmigrant counterparts. Efforts aimed at improving pregnancy care should focus on all women residing in low-income neighborhoods.
| S-EPMC9936351 | biostudies-literature
Project description:AIM: To determine the prevalence of severe acute maternal morbidity (SAMM) worldwide (near miss). METHOD: Systematic review of all available data. The methodology followed a pre-defined protocol, an extensive search strategy of 10 electronic databases as well as other sources. Articles were evaluated according to specified inclusion criteria. Data were extracted using data extraction instrument which collects additional information on the quality of reporting including definitions and identification of cases. Data were entered into a specially constructed database and tabulated using SAS statistical management and analysis software. RESULTS: A total of 30 studies are included in the systematic review. Designs are mainly cross-sectional and 24 were conducted in hospital settings, mostly teaching hospitals. Fourteen studies report on a defined SAMM condition while the remainder use a response to an event such as admission to intensive care unit as a proxy for SAMM. Criteria for identification of cases vary widely across studies. Prevalences vary between 0.80% - 8.23% in studies that use disease-specific criteria while the range is 0.38% - 1.09% in the group that use organ-system based criteria and included unselected group of women. Rates are within the range of 0.01% and 2.99% in studies using management-based criteria. It is not possible to pool data together to provide summary estimates or comparisons between different settings due to variations in case-identification criteria. Nevertheless, there seems to be an inverse trend in prevalence with development status of a country. CONCLUSION: There is a clear need to set uniform criteria to classify patients as SAMM. This standardisation could be made for similar settings separately. An organ-system dysfunction/failure approach is the most epidemiologically sound as it is least open to bias, and thus could permit developing summary estimates.
| S-EPMC516581 | biostudies-literature
Project description:BackgroundOne of the United Nations' Millennium Development Goals of 2000 was to reduce maternal mortality by 75% in 15 y; however, this challenge was not met by many industrialized countries. As average maternal age continues to rise in these countries, associated potentially life-threatening severe maternal morbidity has been understudied. Our primary objective was to examine the associations between maternal age and severe maternal morbidities. The secondary objective was to compare these associations with those for adverse fetal/infant outcomes.Methods and findingsThis was a population-based retrospective cohort study, including all singleton births to women residing in Washington State, US, 1 January 2003-31 December 2013 (n = 828,269). We compared age-specific rates of maternal mortality/severe morbidity (e.g., obstetric shock) and adverse fetal/infant outcomes (e.g., perinatal death). Logistic regression was used to adjust for parity, body mass index, assisted conception, and other potential confounders. We compared crude odds ratios (ORs) and adjusted ORs (AORs) and risk differences and their 95% CIs. Severe maternal morbidity was significantly higher among teenage mothers than among those 25-29 y (crude OR = 1.5, 95% CI 1.5-1.6) and increased exponentially with maternal age over 39 y, from OR = 1.2 (95% CI 1.2-1.3) among women aged 35-39 y to OR = 5.4 (95% CI 2.4-12.5) among women aged ?50 y. The elevated risk of severe morbidity among teen mothers disappeared after adjustment for confounders, except for maternal sepsis (AOR = 1.2, 95% CI 1.1-1.4). Adjusted rates of severe morbidity remained increased among mothers ?35 y, namely, the rates of amniotic fluid embolism (AOR = 8.0, 95% CI 2.7-23.7) and obstetric shock (AOR = 2.9, 95% CI 1.3-6.6) among mothers ?40 y, and renal failure (AOR = 15.9, 95% CI 4.8-52.0), complications of obstetric interventions (AOR = 4.7, 95% CI 2.3-9.5), and intensive care unit (ICU) admission (AOR = 4.8, 95% CI 2.0-11.9) among those 45-49 y. The adjusted risk difference in severe maternal morbidity compared to mothers 25-29 y was 0.9% (95% CI 0.7%-1.2%) for mothers 40-44 y, 1.6% (95% CI 0.7%-2.8%) for mothers 45-49 y, and 6.4% for mothers ?50 y (95% CI 1.7%-18.2%). Similar associations were observed for fetal and infant outcomes; neonatal mortality was elevated in teen mothers (AOR = 1.5, 95% CI 1.2-1.7), while mothers over 29 y had higher risk of stillbirth. The rate of severe maternal morbidity among women over 49 y was higher than the rate of mortality/serious morbidity of their offspring. Despite the large sample size, statistical power was insufficient to examine the association between maternal age and maternal death or very rare severe morbidities.ConclusionsMaternal age-specific incidence of severe morbidity varied by outcome. Older women (?40 y) had significantly elevated rates of some of the most severe, potentially life-threatening morbidities, including renal failure, shock, acute cardiac morbidity, serious complications of obstetric interventions, and ICU admission. These results should improve counselling to women who contemplate delaying childbirth until their forties and provide useful information to their health care providers. This information is also useful for preventive strategies to lower maternal mortality and severe maternal morbidity in developed countries.
| S-EPMC5448726 | biostudies-literature
Project description:ObjectiveTo estimate the frequency of severe maternal morbidity, assess its underlying etiologies, and develop a scoring system to predict its occurrence.Supplemental Digital Content is Available in the Text.MethodsThis was a secondary analysis of a Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network cohort of 115,502 women and their neonates born in 25 hospitals across the United States over a 3-year period. Women were classified as having severe maternal morbidity according to a scoring system that takes into account the occurrence of red blood cell transfusion (more than three units), intubation, unanticipated surgical intervention, organ failure, and intensive care unit admission. The frequency of severe maternal morbidity was calculated and the underlying etiologies determined. Multivariable analysis identified patient factors present on admission that were independently associated with severe maternal morbidity; these were used to develop a prediction model for severe maternal morbidity.ResultsAmong 115,502 women who delivered during the study period, 332 (2.9/1,000 births, 95% confidence interval 2.6-3.2) experienced severe maternal morbidity. Postpartum hemorrhage was responsible for approximately half of severe maternal morbidity. Multiple patient factors were found to be independently associated with severe maternal morbidity and were used to develop a predictive model with an area under the receiver operating characteristic curve of 0.80.ConclusionSevere maternal morbidity occurs in approximately 2.9 per 1,000 births, is most commonly the result of postpartum hemorrhage, and occurs more commonly in association with several identifiable patient characteristics.Level of evidence: II.
| S-EPMC4116103 | biostudies-literature