For most of the 20th century, maternal mortality plummeted. Early in the 20th century, childbirth was extremely dangerous with more than 800 maternal deaths recorded for every 100,000 live births. Sepsis related to unsafe delivery practices and illegal abortions. Accounted for 40% of the deaths but most of those could have been prevented, then, if known principles of asepsis at the time of the delivery had been uniformly applied. You'll note, on this slide, that deaths increased during the influenza epidemic at the end of the second decade. Only 15% of this dramatic drop in maternal mortality during the 20th century occurred after 1950. Most improvement may be attributed to improved delivery practices, whereas some was due to improved abortion practices during the 1960s and 70s. But very little improvement in maternal mortality occurred after 1982. Now the next slide shows some of the same years. From 1987 through 95. But note the difference when we apply the pregnancy related mortality rate definition. The rate is going up all this time. This is when we began the pregnancy, mortality surveillance system at CDC. Through expanding the follow up from 42 days to one year, as well as linking vital records of deliveries with deaths to women of reproductive age. Later on, adding a check box to death certificates to indicate whether a woman of reproductive age had been pregnant in the past year. Transitioning from the ICD9 to the ICD10 codes for causes of death. And investigating records sent in by state health departments. A totally different and disturbing picture of rising death rates emerged. 2009 is the last year reported so far and the rate of 17.8 is more than twice the rate of 7.2 reported for 1987. How much of this increase is real and how much of it is merely a reflection of the reproved, improved reporting. Is not know. However, most agree that the rate of nearly 18 deaths per 100,000 live births is unacceptably high. It's highly unlikely that the healthy people 20/20 goal. Of 11.4 maternal deaths per 100,000 live births will be achieved. In the developing world, the major causes of maternal death are hemorrhage, hypertensive disorders of pregnancy, that is preeclampsia and eclampsia. Prolonged or obstructed labor, infection, sepsis, unsafe abortion, and HIV AIDS related complications. In the developed world, as exemplified by the U.S., hemorrhage, hypertensive disorders of pregnancy, and infection and sepsis still account for slightly more than one-third of the deaths. But obstructed labor, unsafe abortion, and HIV Aids are not in the top ten causes, as you can see in this slide, rather, chronic health conditions. Cardiovascular diseases and Cardiomyopathy, account for almost as many as those other causes combined. When non cardiovascular diseases are included, these indirect causes amount to about four and ten pregnancy related deaths. This is a recent trend that appears to be continuing. Note that this graph, depicts the proportion of deaths attributed to each cause, not the death rates per se. As the pregnancy related mortality rate continues to rise from 1987 to 2009, an increasing proportion. Of all mortality is due to the indirect causes on the right hand side of this graph, while a decreasing proportion, but not necessarily a decreasing rate of direct causes is occurring. Now the US is notable for its health disparities among minorities. Particularly among African Americans. This long standing and terrible issue is striking for maternal deaths. Over time, African American women have suffered three to four times the risk of death. And if anything, the gap is, has increased. While pregnancy related mortality has more than doubled over the last 25 years among African American women. The black white gap cannot be explained by so called traditional risk factors. As shown in this table, when maternal age, mete, marital status. Adequacy of prenatal care, gestational age at delivery, urban or rural residence, geographic region, birth order, and birth weight, were controlled, the gap remained. That's seen in both the crude odds ratio, and the adjusted odds ratio. And note that it was greatest when the mothers delivered normal weight infants in their first to third births. This finding is similar to what we found for risk of very low birth weight in which college educated African American women. Married to college educated partners, who were delivering their first, or second, births, in their 20s, and with early prenatal care, had a nearly threefold risk of delivering a very low birth weight infant, when compared to white women with similar characteristics. Disparities also appear across states. As can be seen in this map. It seems that rates vary by as much as five fold, although some rates are unstable because of small populations in some states. The bottom line is that pregnancy related mortality is apparently increasing in the US, owing largely to increases in indirect causes related to exacerbation's of chronic conditions. Death rates are particularly high among African American mothers. But, what are the reasons for these trends? Some answers may be found in concomitant trends in social, environmental, and behavioral factors, that are outside the purview of obstetrics, but not outside the purview of public health. It's no secret that Americans are experiencing an epidemic of obesity and type two diabetes. This is graphically illustrated by the data from the behavioral risk factor surveillance surveys, over time. Beginning in 1994 going through 2010,the darker colors are showing how obesity on the left and diabetes on the right, increase every year and reach proportions that never were measured early in the 1990s. This is a very brief period of time for this amount of change to occur. And it shows that there is this clear association between obesity and diabetes. Not surprisingly gestational diabetes is on the rise. Having doubled in the ten years between 1994 and 2004. In turn, diabetes is a chronic condition that increases maternal mortality risk. Obesity is also a risk factor for uterine atony, which is also increasing and is a risk factor for postpartum hemorrhage. Further, chronic hypertension and increased BMI are associated as body mass index increases. The risk of chronic hypertension increases dramatically. Perhaps not as well appreciated is the steady rise in maternal age. Age specific birth rates for women in their 30s and 40s have been steadily increasing over the last two decades. While rates have been declining among younger women. This can also be seen by the higher proportion of first births that are to older women. Advanced maternal age is a potent risk factor for maternal mortality. And the trend toward increasing average age at childbirth may be contributing to the rising maternal mortality rate. One of the reasons is that hypertension increases dramatically with age. The high proportion of pregnancy related deaths associated with cardiovascular conditions. Attest to the importance of these issues. As shown in this graph, both increasing maternal age and increasing BMI for all ages, contribute to increased risks associated with chronic health conditions. There are racial and ethnic disparities. Most notably, in chronic hypertension among non Hispanic black women. Another strong reason for the higher proportion in maternal deaths associated with indirect causes is the increasing number of women with major health conditions, such as congenital heart disease. Who are surviving into adulthood. I'd like to close out this segment by mentioning some successes. Anesthesia related maternal deaths account for less than 2% of all pregnancy related deaths, but they declined almost declined almost 60% from the 1980s to the 1990s. Also, deaths due to ectopic pregnancy and induced abortion have been dramatically reduced and are no longer major causes of pregnancy related mortality in the United States.
