Maternal death
According to the United Nations Maternal Mortality Estimation Inter-agency Group, which consists of representatives from theWorld Health Organization (WHO), United Nations Children's Fund (UNICEF), the United Nations Population Fund(UNFPA), United Nations Population Division, the World Bankand world-renowned academics, maternal death is:
"The death of a woman while pregnant or within 42 days of termination of pregnancy, irrespective of the duration and the site of the pregnancy, from any cause related to or aggravated by the pregnancy or its management, but not from accidental or incidental causes." [1]
原因: 產後出血，感染，不當墮胎，高血壓，難產，血栓與其它疾病
Factors that increase maternal death can be direct or indirect. Generally, there is a distinction between a direct maternal death that is the result of a complication of the pregnancy, delivery, or management of the two, and an indirect maternal death[2] that is a pregnancy-related death in a patient with a preexisting or newly developed health problem unrelated to pregnancy. Fatalities during but unrelated to a pregnancy are termed accidental, incidental, or nonobstetrical maternal deaths.
The WHO notes that in 2014 the major direct causes of maternal deaths globally are: severe bleeding/hemorrhage (27%), infections (11%), unsafe abortions (8%), high blood pressure during pregnancy (pre-eclampsia and eclampsia) (14%), obstructed labour (9%), blood clots/embolism (3%) and pre-existing conditions (28%).[3] Indirect causes are malaria, anaemia,[4] HIV/AIDS, and cardiovascular disease, all of which may complicate pregnancy or be aggravated by it.
Sociodemographic factors such as age, access to resources and income level are significant indicators of maternal outcomes. Young mothers face higher risks of complications and death during pregnancy than older mothers,[5] especially adolescents aged 15 years or younger.[6] Adolescents have higher risks for postpartum hemorrhage, puerperal endometritis, operative vaginal delivery, episiotomy, low birth weight,preterm delivery, and small-for-gestational-age infants, all of which can lead to maternal death.[6] Structural support and family support influences maternal outcomes. Furthermore, social disadvantage and social isolation adversely affects maternal health which can lead to increases in maternal death.[7] Additionally, lack of access to skilled medical care during childbirth, the travel distance to the nearest clinic to receive proper care, number of prior births, barriers to accessing prenatal medical care and poor infrastructure all increase maternal deaths.
Unsafe abortion is another major cause of maternal death. According to the World Health Organization, every eight minutes a woman dies from complications arising from unsafe abortions. Complications include hemorrhage, infection, sepsis and genital trauma [8] Globally, preventable deaths from improperly performed procedures constitute 13% of maternal mortality, and 25% or more in some countries where maternal mortality from other causes is relatively low, making unsafe abortion the leading single cause of maternal mortality worldwide.[9]
研究報告：全球每年約27萬5千孕產婦死亡，45%發生在產後24小時，99%在發展中國家
Maternal deaths and disabilities are leading contributors in women's disease burden with an estimated 275,000 women killed each year in childbirth and pregnancy worldwide.[10] In 2011, there were approximately 273,500 maternal deaths (uncertainty range, 256,300 to 291,700).[11] Forty-five percent of postpartum deaths occur within 24 hours.[12] Ninety-nine percent of maternal deaths occur in developing countries.[3]
Measurement of Maternal Death[edit]
The four measures of maternal death are the maternal mortality ratio (MMR), maternal mortality rate, lifetime risk of maternal death and proportion of maternal deaths among deaths of women of reproductive years (PM). The MMR is used as a measure of the quality of a health care system.
Maternal mortality ratio (MMR): the ratio of the number of maternal deaths during a given time period per 100,000 live births during the same time-period.[1]
Maternal mortality rate (MMRate): the number of maternal deaths in a population divided by the number of women of reproductive age, usually expressed per 1,000 women.[1]
Lifetime risk of maternal death: refers to the probability that a 15-year-old female will die eventually from a maternal cause if she experiences throughout her lifetime the risks of maternal death and the overall levels of fertility and mortality that are observed for a given population. The adult lifetime risk of maternal mortality can be derived using either the maternal mortality ratio(MMR), or the maternal mortality rate(MMRate). [1]
Proportion of maternal deaths among deaths of women of reproductive age (PM): the number of maternal deaths in a given time period divided by the total deaths among women aged 15–49 years.[13]
Approaches to measuring maternal mortality includes civil registration system, household surveys, census, reproductive age mortality studies (RAMOS) and verbal autopsies.[14]
Global Trends[edit]
According to the 2010 United Nations Population Fund report, developing nations account for ninety-nine percent of maternal deaths with majority of those deaths occurring in Sub-Saharan Africa and Southern Asia.[14] Globally, high and middle income countries experience lower maternal deaths than low income countries. The Human Development Index (HDI) accounts for between 82 and 85 percent of the maternal mortality rates among countries.[15] In most cases, high rates of maternal deaths occur in the same countries that have high rates of infant mortality. These trends are a reflection that higher income countries have stronger healthcare infrastructure, medical and healthcare personnel, use more advanced medical technologies and have less barriers to accessing care than low income countries. Therefore, in low income countries, the most common cause of maternal death is obstetrical hemorrhage, followed by hypertensive disorders of pregnancy, in contrast to high income countries, for which the most common cause is thromboembolism.[16]
At a country level, India (19% or 56,000) and Nigeria (14% or 40,000) accounted for roughly one third of the maternal deaths in 2010. Democratic Republic of the Congo, Pakistan, Sudan, Indonesia, Ethiopia,United Republic of Tanzania, Bangladesh and Afghanistan comprised between 3 to 5 percent of maternal deaths each.[14] These ten countries combined accounted for 60% of all the maternal deaths in 2010 according to the United Nations Population Fund report. Countries with the lowest maternal deaths were Estonia, Greece and Singapore.[17]
In the United States, the maternal death rate averaged 9.1 maternal deaths per 100,000 live births during the years 1979-1986,[18] but then rose rapidly to 14 for every 100,000 patients in 2000 to 24 per every 100,000 patients in 2008.[19] According to the Center for Disease Control and Prevention, approximately 650 women die in the United States each year as a result of pregnancy and delivery complications.[20]
Variation Within Countries[edit]
There are significant maternal mortality intracountry variations, especially in nations with large equality gaps in income and education and high healthcare disparities. Women living in rural areas experience higher maternal mortality than women living in urban and suburban centers because [21] those living in wealthier households, having higher education, or living in urban areas, have higher use of healthcare services than their poorer, less-educated, or rural counterparts.[22] There are also racial and ethnicdisparities in maternal health outcomes which increases maternal mortality in marginalized groups.[23]
