A thirty-year review of maternal mortality in Oklahoma, 1950 through 1979

Oklahoma's Maternal Mortality Committee has been active since 1941. During the 30-year period 1950 through 1979, the committee reviewed in detail 75.9% of the pregnancy-related deaths that occurred in Oklahoma. The maternal mortality ratio in 1950 was 95.1/100,000 live births, and for 1979 it was 8.1/100,000 live births, a decrease of 91.5%. The risk of death from childbearing remained greater for black women than for American Indian or white women throughout the three decades. For American Indian women, the risk of death associated with pregnancy has decreased and is almost equal to the risk for white women. The Maternal Mortality Committee estimated that two thirds of Oklahoma's maternal deaths were preventable. The proportion of deaths judged preventable did not vary substantially during the study period. We conclude that maternal mortality in Oklahoma can be reduced to fewer than three deaths per 100,000 live births. Intensive monitoring and investigation of deaths and their causes by local maternal mortality committees continues to be an important mechanism for obtaining information to assist health workers in the prevention of deaths.     

Maternal deaths in an urban perinatal network, 1992-1998

OBJECTIVE: The object of this study was to use an in-depth peer-review process to determine the maternal mortality ratio at a single urban perinatal center and to identify factors associated with fatal outcomes to elucidate opportunities for preventive measures to reduce the maternal mortality ratio. STUDY DESIGN: Between 1992 and 1998 all maternal deaths occurring within our perinatal network were identified. A peer-review committee was established to review all available data for each death to determine the underlying cause of death, whether it was related to pregnancy, and whether the death was potentially preventable. RESULTS: There were 131,500 births and 42 maternal deaths, for a maternal mortality ratio of 31.9 maternal deaths per 100,000 live births. The adjusted pregnancy-related maternal mortality ratio was 22.8 maternal deaths per 100,000 live births, with 37% of those deaths (11/30) deemed potentially preventable and a provider factor cited in >80% of these. Pulmonary embolus and cardiac disease together accounted for 40% of the pregnancy-related deaths. CONCLUSION: Local maternal mortality ratios identified through a peer-review process indicate that the magnitude of the problem is much greater than is recognized through national death certificate data. The high proportion of potentially preventable maternal deaths indicates the need for improvement in both patient and provider education if we are to reduce the maternal mortality ratio to 3.3 maternal deaths per 100,000 live births, the stated national health goal of Healthy People 2000.     

Cesarean delivery and postpartum mortality among primiparas in Washington State, 1987-1996(1)

OBJECTIVE: To examine the association between delivery method and mortality within 6 months of delivery among primiparas. METHODS: We conducted a population-based, retrospective cohort analysis using statewide, maternally linked birth certificate, hospital discharge, and death certificate data. The present cohort was all primiparas who gave birth to live-born infants in civilian hospitals in Washington State from January 1, 1987 through December 31, 1996 (n = 265,471). Odd ratios (OR) and 95% confidence intervals (CI) were calculated for overall mortality, pregnancy-related mortality, and pregnancy-unrelated mortality associated with delivery method. RESULTS: Thirty-two women (12.1 per 100,000 singleton live births) died within 6 months of delivery of their first child. Eleven of 32 deaths were pregnancy related (4.1 per 100,000 singleton live births, 95% CI 1.6, 6.5), and 21 of the 32 deaths were not pregnancy related (7.9 per 100,000 singleton live births, 95% CI 4.5, 11.3). The pregnancy-related mortality rate was higher among women delivered by cesarean (10.3/100,000) than among women delivered vaginally (2.4/100,000). In logistic regression analyses, women who had cesarean delivery were not at significantly higher risk of death overall after adjustment for maternal age (OR 1.7, 95% CI 0.3, 3.6), pregnancy-related death after adjustment for maternal age and severe preeclampsia (OR 2.2, 95% CI 0.6, 7.9), or pregnancy-unrelated death after adjustment for maternal age and marital status (OR 0.9, 95% CI 0.3, 2.7), relative to women who had vaginal delivery. CONCLUSION: Cesarean delivery might be a marker for serious preexisting morbidities associated with increased mortality risk rather than a risk factor for death in and of itself. Data from additional sources such as medical records and autopsy reports are necessary to disentangle preexisting mortality risk from risk associated solely with delivery method.     

Pregnancy-related mortality due to cardiomyopathy: United States, 1991-1997

OBJECTIVE: To describe characteristics and risk factors for pregnancy-related deaths due to cardiomyopathy during 1991-1997 and to assess reasons for the increasing trend in reporting of pregnancy-related deaths due to cardiomyopathy from 1979 through 1997. METHODS: We used data from the Centers for Disease Control (CDC) and Prevention's Pregnancy Mortality Surveillance System to examine pregnancy-related deaths due to cardiomyopathy from 1991 through 1997. The pregnancy-related mortality ratio for cardiomyopathy was defined as the number of pregnancy-related deaths from cardiomyopathy per 100,000 live births. Cardiomyopathy was classified as peripartum cardiomyopathy or cardiomyopathy due to other causes. RESULTS: Of the 245 cardiomyopathy deaths that occurred during 1991-1997, 171 (70%) were due to peripartum cardiomyopathy. The cause-specific pregnancy-related mortality ratio was 0.88 per 100,000 live births. Mortality increased as maternal age increased. Black women were 6.4 times as likely to die from cardiomyopathy as white women. Among peripartum cardiomyopathy cases in which the interval from the end of pregnancy was known, 2% died undelivered, 48% died within 42 days of delivery, and 50% died between 43 days and 1 year postpartum. CONCLUSION: Cardiomyopathy accounts for an increasing proportion of reported pregnancy-related deaths, and the more than six-fold excess risk of death from cardiomyopathy among black women is larger than that for any other cause of death. The increased reporting of these deaths might be largely due to improved case ascertainment. Further studies are required to estimate the prevalence of cardiomyopathy and identify modifiable risk factors associated with these deaths and the reasons for this racial disparity.     

Pregnancy-related mortality from preeclampsia and eclampsia

OBJECTIVE: To examine the role of preeclampsia and eclampsia in pregnancy-related mortality. METHODS: We used data from the Centers for Disease Control and Prevention's Pregnancy Mortality Surveillance System to examine pregnancy-related deaths from preeclampsia and eclampsia from 1979 to 1992. The pregnancy-related mortality ratio for preeclampsia-eclampsia was defined as the number of deaths from preeclampsia and eclampsia per 100,000 live births. Case-fatality rates for 1988-1992 were calculated for preeclampsia and eclampsia deaths per 10,000 cases during the delivery hospitalization, using the National Hospital Discharge Survey. RESULTS: Of 4024 pregnancy-related deaths at 20 weeks' or more gestation in 1979-1992, 790 were due to preeclampsia or eclampsia (1.5 deaths/100,000 live births). Mortality from preeclampsia and eclampsia increased with increasing maternal age. The highest risk of death was at gestational age 20-28 weeks and after the first live birth. Black women were 3.1 times more likely to die from preeclampsia or eclampsia as white women. Women who had received no prenatal care had a higher risk of death from preeclampsia or eclampsia than women who had received any level of prenatal care. The overall preeclampsia-eclampsia case-fatality rate was 6.4 per 10,000 cases at delivery, and was twice as high for black women as for white women. CONCLUSION: The continuing racial disparity in mortality from preeclampsia and eclampsia emphasizes the need to identify those differences that contribute to excess mortality among black women, and to develop specific interventions to reduce mortality from preeclampsia and eclampsia among all women.     

Maternal mortality in the United States: report from the Maternal Mortality Collaborative

To better define the incidence, causes, and risk factors associated with maternal deaths, the Maternal Mortality Collaborative in 1983 initiated national voluntary surveillance of maternal mortality. The Maternal Mortality Collaborative reported 601 maternal deaths from 19 reporting areas for 1980-1985, representing a maternal mortality ratio of 14.1 per 100,000 live births. Overall, 37% more maternal deaths were reported by the Maternal Mortality Collaborative than by the National Center for Health Statistics for these reporting areas. Older women and women of black and other races continued to have higher mortality than younger women and white women. The five most common causes of death for all reported cases were embolism, nonobstetric injuries, hypertensive disease of pregnancy, ectopic pregnancy, and obstetric hemorrhage. Compared with national maternal mortality for 1974-1978, ratios were lower for all causes except for indirect causes, anesthesia, and cerebrovascular accidents. Fatal injuries among pregnant women are not commonly reported to maternal mortality committees. As maternal mortality from direct obstetric causes continues to decline, clinicians will need to emphasize preventing deaths from nonobstetric causes.     

Pregnancy-related mortality in the United States, 1991-1997

OBJECTIVE: To describe trends in pregnancy-related mortality and risk factors for pregnancy-related deaths in the United States for the years 1991 through 1997. METHODS: In collaboration with the American College of Obstetricians and Gynecologists and state health departments, the Pregnancy Mortality Surveillance System, part of the Division of Reproductive Health at the Centers for Disease Control and Prevention, has collected information on all reported pregnancy-related deaths occurring since 1979. Data include those present on death certificates and, when available, matching birth or fetal death certificates. Data are reviewed and coded by clinically experienced epidemiologists. The pregnancy-related mortality ratio was defined as pregnancy-related deaths per 100,000 live births. RESULTS: The reported pregnancy-related mortality ratio increased from 10.3 in 1991 to 12.9 in 1997. An increased risk of pregnancy-related death was found for black women, older women, and women with no prenatal care. The leading causes of death were embolism, hemorrhage, and other medical conditions, although the percent of all pregnancy-related deaths caused by hemorrhage declined from 28% in the early 1980s to 18% in the current study period. CONCLUSION: The reported pregnancy-related mortality ratio has increased, probably because of improved identification of pregnancy-related deaths. Black women continue to have an almost four-fold increased risk of pregnancy-related death, the greatest disparity among the maternal and child health indicators. Although review of pregnancy-related deaths by states remains an important public health function, such work must be expanded to identify factors that influence the survival of women with serious pregnancy complications.     

Causes of maternal death. A 10-year case analysis]

The causes of maternal deaths in our hospital from 1981 to 1989 were analysed. There were 12,819 live births and 6 maternal deaths during this period, a maternal mortality rate of 46.69/per 100,000. The main cause of maternal deaths was acute fatty liver of pregnancy (50%), and next cardiac disease, acute hemorrhagic necrotic pancreatitis and hemorrhage of subarachnoid space (each 16.67%). There was no death due to obstetric hemorrhage, pregnancy induced hypertension syndrome or ectopic pregnancy. It is suggested that needle biopsy of the liver should be done for pregnant women with jaundice of unknown cause. Pregnant women with cardiac disease should be under the care of both obstetrician and internist in collaboration and cesarean section is indicated when the woman's cardiac function remains at grade 3 or 4.     

Maternal mortality in Switzerland 1985-1994

The maternal mortality rate in the west has dropped drastically in the last 100 years. As yet there are no detailed numbers of the actual causes of death for Switzerland. We re-evaluated the anonymous patient documentation for the years 1985-1994 using the officially registered (ICD-8) cases of maternal mortality. 45 deaths out of 812,825 births remained from the original 76 registered cases, which corresponds to a direct maternal mortality of 5.4/100,000 live births. The other cases had to be reclassified (indirect, late or pregnancy-related obstetric deaths). The majority of the deaths were caused by thromboembolism (15%). The mortality rate for cesarean section was 0.09 per thousand. The large number of reclassified cases shows that further teaching is necessary in the completion of the death certificate. In the attempt to reduce maternal mortality, one has to direct attention to the consequent prophylaxis of thromboembolism and induce a premature birth in cases of HELLP syndrome.     

Estimating maternal mortality and causes in South Africa: National and provincial levels

Objectives

maternal mortality estimates for South Africa have methodological weaknesses. This study uses the Growth Balance Method to adjust reported household female deaths and pregnancy-related deaths and the relational Gompertz model to adjust reported number of live births and estimate maternal mortality in South Africa at national and provincial level; examines the potential impact of HIV/AIDS prevalence; and investigates the recorded direct causes of maternal mortality.

Design

data from the 2001 Census, 2007 Community Survey and death registrations were utilised. Information on household deaths, including pregnancy-related deaths was collected from the aforementioned census and survey.

Setting

enumerated households in the 2001 Census and a nationally representative sample of 250,348 households in the 2007 Community Survey.

Participants

information about members of households who died in the preceding 12 months was collected, and of these deaths whether there were women aged 15–49 who died while pregnant or within 42 days after childbirth.

Findings

maternal mortality ratio of 764 per 100,000 live births in 2007, ranging from 102 per 100,000 live births in the Western Cape province to 1639 in the Eastern Cape. Maternal infections and parasitic diseases as well as other maternal diseases complicating pregnancy, childbirth and the puerperium are the major causes. The study found a weak correlation between provincial HIVprevalence and maternal mortality ratio.

Conclusion

despite strategies to improve maternal and child health, maternal mortality remains high in South Africa and it is unlikely that the Millennnium Developmemnt Goal of reducing maternal will be achieved.     

Pregnancy-related deaths due to pulmonary embolism in Sweden

BACKGROUND: The objective of this study was to report deaths from amniotic fluid embolism (AFE) and pregnancy-related venous thromboembolism (VTE), to study contributing factors, and to analyse mortality trends. METHODS: Using the Swedish Cause of Death Register (CDR), we identified all women aged 15-44, who died during 1990-1999, with VTE or AFE coded as the underlying or contributory cause of death. We scrutinised medical records, and women who had died during pregnancy or within 6 weeks of terminated pregnancy were included. We also used data from the Medical Birth Register (MBR) on incident and fatal cases. Mortality data from the 1970s and 1980s were based on previous studies, in which cases were identified through register linkage (CDR and MBR). RESULTS: Five women died of AFE and 10 of VTE - 6 in early pregnancy - during the 1990 s. Five of the cases were not registered as maternal deaths. Only 4 cases were reported as pregnancy-related deaths from pulmonary embolism (PE). Cesarean section/surgery without thromboprophylaxis, overweight, severe intercurrent disease, delays in seeking health care, and verbal miscommunication were contributing factors in the VTE cases. VTE mortality rates (pregnancy >28 weeks and/or a registered birth) were 1.0 (0.5-1.8), 0.8 (0.3-1.6), and 0.4 (0.1-1.0) per 100,000 live births during the 1970s, 1980s and 1990 s, respectively; the corresponding respective figures for AFE were 1.0 (0.5-1.8), 1.1 (0.6-2.1), and 0.5 (0.2-1.1) per 100,000 live births. The case fatality rate for VTE decreased from 4.5% in the 1970s, to 0.6% in the 1990 s, paralleled with quadrupled incidence. The case fatality rate for AFE was unaltered and high, around 45%, during those 3 decades. CONCLUSIONS: Mortality from pregnancy-related PE in Sweden is in the lowest range ever reported, and shows a downward trend during the 1990 s, with a shift towards early pregnancy. In order to monitor mortality trends, death certificate quality must improve, and registers must be linked routinely.     

Trends in maternal mortality in resident vs. migrant women in Shanghai, China, 2000-2009: a register-based analysis

Although Shanghai has good maternal health indicators, it also has a large in-migrating population, which has made control of maternal mortality a major challenge. This study analyzed maternal mortality and causes of death in pregnant women in Shanghai in the ten years from 2000 to 2009, comparing resident and migrant women. All live births were registered and every maternal death audited. The number of live births rose from 84,898 in 2000 to 187,335 in 2009. The number of migrants increased 4.6 times, while the proportion of live births to migrant women increased from 27% to 55%. There were 262 maternal deaths, 55 in Shanghai residents and 207 in migrant women (78.9% of the total). Most deaths in migrant women were due to illegal delivery. Three policy changes focusing on maternal health greatly reduced deaths: low-cost delivery services were established for migrant women in maternity hospitals, five obstetric emergency care and referral centres were created in general hospitals, and training for health professionals and health education for women were instituted. Maternal mortality in Shanghai decreased steadily from 2000 to 2009, reaching 10 per 100,000 live births in 2009. Among Shanghai permanent residents the ratio was below ten in most of those years, while among migrant women it declined sharply from 58 to 12 per 100,000 live births.     

Maternal mortality in the U.S. Department of Defense, 1993-1998

OBJECTIVE: To determine the maternal mortality ratio (MMR) in Department of Defense medical facilities from 1993 to 1998. STUDY DESIGN: We conducted a retrospective review of birth data from military medical facilities using the Standard Inpatient Data Records from 1993 through 1998. The total number of live births and dispositions due to maternal death were obtained. RESULTS: Twenty-two maternal deaths occurred in the study time out of 398,107 live births, for an MMR of 5.5 per 100,000 live births. The ratiosfor the service branches were: Army 7.0, Navy 5.3 and Air Force 3.6. The leading cause of death was embolic disease. CONCLUSION: The military MMR is closer to the Healthy People 2010 goal of 3.3 than is the national ratio, 13.2. Improved reporting of cases, patient education and treating high-risk conditions may help further decrease pregnancy-related mortality.     

Underreporting of pregnancy-related mortality in the United States and Europe

OBJECTIVE: Available maternal mortality statistics do not allow valid international comparisons. Our objective was to uniformly measure underreporting of mortality from pregnancy in official statistics from selected regions within the U.S. and Europe, and to provide comparable revised profiles of pregnancy-related mortality. METHODS: We developed a standardized enhanced method to uniformly identify and classify pregnancy-associated deaths from 2 U.S. states, Massachusetts and North Carolina, and 2 European countries, Finland and France, for the years 1999-2000. Identification method included the use of all data available from the death certificate as well as computerized linkage of births and deaths registers. All cases were reviewed and classified by an international panel of experts. RESULTS: Four-hundred-and-four pregnancy-associated deaths were identified and reviewed. Underestimation of mortality causally related to pregnancy based on International Classification of Diseases cause-of-death codes alone varied from 22% in France to 93% in Massachusetts. Underreporting was greater in the regions with lower initial maternal mortality ratios. The distribution of causes of pregnancy-related mortality was specific to each region. The leading causes of death were cardiovascular conditions in Massachusetts; hemorrhage, pregnancy-induced hypertension, and peripartum cardiomyopathy in North Carolina; noncardiovascular medical conditions in Finland; and hemorrhage in France. CONCLUSION: This study shows the limitations of maternal mortality statistics based on International Classification of Diseases cause-of-death codes alone. Linkage of births and deaths registers should routinely be used in the ascertainment of pregnancy-related deaths. In addition, extension of the definition of a maternal death should be considered. Beyond pregnancy-related mortality ratios, considering the specific distribution of causes-of-death is important to define prevention strategies.     

Venous thromboembolism as a cause of severe maternal morbidity and mortality in the United States

In the U.S., deaths due to pulmonary embolism (PE) account for 9.2% of all pregnancy-related deaths or approximately 1.5 deaths per 100,000 live births. Maternal deaths and maternal morbidity due to PE are more common among women who deliver by cesarean section. In the past decade, the clinical community has increasingly adopted venous thromboembolism (VTE) guidelines and thromboprophylaxis recommendations for pregnant women. Although deep vein thrombosis rates have decreased during this time-period, PE rates have remained relatively unchanged in pregnancy hospitalizations and as a cause of maternal mortality. Changes in the health profile of women who become pregnant, particularly due to maternal age and co-morbidities, needs more attention to better understand the impact of VTE risk during pregnancy and the postpartum period.     

Four main reasons of maternal death in Poland between 1991-2000

Maternal death during pregnancy, labour and puerperium constitutes the main problem of prenatal medicine and still a major public health topic. In this work we analyses maternal deaths in Poland between 1991-2000. There were 4,404,641 live births and 462 maternal deaths. Among them there were 402 direct ("true") maternal deaths with mortality rate 9.1 per 100,000 live births and 60 indirect maternal deaths (rate 1.4). There were 218 cases of pregnancy associated deaths (rate 4.9). The main causes of direct maternal deaths were as follows: haemorrhage--33.6% (rate 3.1), sepsis--27.3% (rate 2.5), amniotic fluid embolism--22.4% (rate 2.0) and pregnancy induced hypertension 16.7% (rate 1.5). Increasing maternal age is one of important risk factor for mortality. Over 30% of direct pregnancy related deaths were noted within women above 35 years. Unsatisfactory antenatal care, management deficiency and patient's neglect were main risk factor foe fatal outcome. Practical conclusions should be issued as general rules, instructions and recommendations. Between one third to one half of the maternal deaths are considered to have been preventable.     

Maternal mortality in the United States, 1979-1986

To understand better the epidemiology and to describe the causes of maternal death, we reviewed all identified maternal deaths in the United States and Puerto Rico for 1979-1986. The overall maternal mortality ratio for the period was 9.1 deaths per 100,000 live births. The ratios increased with age and were higher among women of black and other minority races than among white women for all age groups. The causes of death varied for different outcomes of pregnancy; pulmonary embolism was the leading cause of death after a live birth. Unmarried women had a higher risk of death than married women. The risk of death increased with increasing live-birth order, except for primiparas. In order to develop strategies to reduce the risk of maternal death in the United States, future studies should include expanded information about each death, which will allow better understanding of factors associated with maternal mortality.     

Maternal mortality in Denmark, 1985–1994

Objectives

In Denmark, maternal mortality has been reported over the last century, both locally through hospital reports and in national registries. The purpose of this study was to analyze data from national medical registries of pregnancy-related deaths in Denmark 1985–1994 and to classify them according to the UK Confidential Enquiry into Maternal Deaths (CEMD).

Study design

All deaths of women with a registered pregnancy within 12 months prior to the death were identified by comparing the Danish medical registries, death certificates, and relevant codes according to International Classification of Diseases (ICD-10). All cases were classified using the UK CEMD classification. Cases of maternal death were further evaluated by an audit group.

Results

311 cases were classified. 92 deaths (29.6%) occurred ≤42 days after termination of pregnancy. Of these, 30 were classified as direct obstetric deaths, 30 as indirect obstetric deaths, and 32 as fortuitous deaths. Among the late pregnancy-related deaths (>42 days), 1 woman died from a direct obstetric cause, 46 from indirect causes, and 172 from fortuitous causes. Hypertensive disorders of pregnancy were the major cause of direct maternal deaths. The rate of maternal deaths constituted 9.8/100,000 maternities (i.e. the number of women delivering registrable live births at any gestation or stillbirths at 24 weeks of gestation or later).

Conclusion

This is the first systematic report on deaths in Denmark based on data from national registries. The maternal mortality rate in Denmark is comparable to the rates in other developed countries. Fortunately, statistics are low, but each case represents potential learning.Obstetric care has changed and classification methods differ between countries. Prospective registration and registry linkage seem to be a way to ensure completion. This retrospective study has provided the background for a prospective study on registration and evaluation of maternal mortality in Denmark.     

Maternal mortality in Hong Kong 1961–1985

Summary. The maternal mortality rate in Hong Kong feil from 0·45/1000 total births in 1961 to 0·05/1000 total births in 1985. During the period between 1961 and 1985 there were a total of 438 maternal deaths and 2 193 012 births. Of the 438 deaths 150 (34%) were due to haemor-rhage during pregnancy and childbirth (ICD 640, 641, 666), 89 (20%) were due to pre-eclampsia (ICD 642, 643) and 60 (13·7%) were due to ectopic pregnancy (ICD 633). Comparison of maternal deaths by cause between the periods 1961–1965 and 1981–1985 showed an 86% reduc-tion in deaths due to haemorrhage and pre-eclampsia and a 72% reduc-tion in deaths due to ectopic pregnancy. Pulmonary embolism was not a major cause of maternal mortality.     

Analysis of the pregnancy-related deaths within the last two decades: a university hospital-based study from Turkey

OBJECTIVE: To analyse the causes of pregnancy-related deaths at Ondokuz Mayis University Hospital. STUDY DESIGN: The death of a woman while pregnant or within 42 days of termination of pregnancy regardless of the cause of death, including accidental or incidental causes, was accepted as a 'pregnancy-related death'. Such deaths were evaluated in Ondokuz Mayls University Hospital in the years 1978-1997 inclusive. They were classified as direct obstetric, indirect obstetric, and accidental or incidental deaths. RESULTS: Eighty-seven pregnancy-related deaths were identified via hospital death records. Maternal mortality ratio was calculated to be 822.2 per 100,000 live births. Seventy seven percent of the deaths were due to direct obstetric causes; most commonly due to toxemia, infection and hemorrhage. CONCLUSION: Direct obstetric deaths, which are largely preventable with proper antenatal care and health services, are still problems in our country.