The spontaneous death or loss of a fetus during pregnancy is termed a fetal death. In the United States, national data on fetal deaths are available for losses at ≥20 weeks' gestation.* Deaths occurring during this period of pregnancy are commonly known as stillbirths. In 2017, approximately 23,000 fetal deaths were reported in the United States (1). Racial/ethnic disparities exist in the fetal mortality rate; however, much of the known disparity in fetal deaths is unexplained (2). CDC analyzed 2015-2017 U.S. fetal death report data and found that non-Hispanic Black (Black) women had more than twice the fetal mortality rate compared with non-Hispanic White (White) women and Hispanic women. Fetal mortality rates also varied by maternal state of residence. Cause of death analyses were conducted for jurisdictions where >50% of reports had a cause of death specified. Still, even in these jurisdictions, approximately 31% of fetal deaths had no cause of death reported on a fetal death report. There were differences by race and Hispanic origin in causes of death, with Black women having three times the rate of fetal deaths because of maternal complications compared with White women. The disparities suggest opportunities for prevention to reduce the U.S. fetal mortality rate. Improved documentation of cause of death on fetal death reports might help identify preventable causes and guide prevention efforts.

BACKGROUND: Maternal mortality ratios (MMR) appear to have increased in the United States over the last decade. Three potential contributing factors are: 1) a shifting maternal age distribution, 2) changes in age-specific MMR, and 3) the addition of a checkbox indicating recent pregnancy on the death certificate. OBJECTIVE: Determine the contribution of rising maternal age on changes in MMR from 1978-2012, and estimate the contribution of the pregnancy checkbox on increases in MMR over the last decade. STUDY DESIGN: Kitagawa decomposition analyses were conducted to partition the maternal age contribution to the MMR increase into two components: changes due to a shifting maternal age distribution, and changes due to higher age-specific mortality ratios. We used National Vital Statistics System (NVSS) natality and mortality data. The following five-year groupings were used: 1978-1982, 1988-1992, 1998-2002, and 2008-2012. Changes in age-specific MMRs among states that adopted the standard pregnancy checkbox onto their death certificate before 2008 (n=23) were compared with states that had not adopted the standard pregnancy checkbox on their death certificate by the end of 2012 (n=11) to estimate the percentage increase in the MMR due to the pregnancy checkbox. RESULTS: Overall U.S. MMRs for 1978-1982, 1988-1992, and 1998-2002 were 9.0, 8.1, and 9.1 deaths per 100,000 live births, respectively. There was a modest increase in the MMR between 1998-2002 and 2008-2012 in the 11 states that had not adopted the standard pregnancy checkbox on their death certificate by the end of 2012 (8.6 and 9.9 deaths per 100,000 respectively). However, the MMR more than doubled between 1998-2002 and 2008-2012 in the 23 states that adopted the standard pregnancy checkbox (9.0 to 22.4); this dramatic rise was almost entirely attributable to increases in age-specific MMRs (94.9%) as opposed to increases in maternal age (5.1%), with an estimated 90% of the observed change reflecting the change in maternal death identification rather than a real change in age-specific rates alone. Of all age categories, women ages 40 and older in states that adopted the standard pregnancy checkbox had the largest increase in MMR-from 31.9 to 200.5-a relative increase of 528%, which accounted for nearly one-third of the overall increase. An estimated 28.8% of the observed change was potentially due to maternal death misclassification among women ≥40. CONCLUSION: Increasing age-specific maternal mortality seems to be contributing more heavily than a changing maternal age distribution to recent increases in MMR. In states with the standard pregnancy checkbox, the vast majority of the observed change in MMR over the last decade was estimated to be due to the pregnancy checkbox, with the greatest change in MMR occurring in women ages ≥40 years. The addition of a pregnancy checkbox on state death certificates appears to be increasing case identification, but may also be leading to maternal death misclassification, particularly for women ages ≥40 years.

The number of births in the United States declined by 1% between 2010 and 2011, to a total of 3,953,593. The general fertility rate also declined by 1% to 63.2 births per 1000 women, the lowest rate ever reported. The total fertility rate was down by 2% in 2011 (to 1894.5 births per 1000 women). The teenage birth rate fell to another historic low in 2011, 31.3 births per 1000 women. Birth rates also declined for women aged 20 to 29 years, but the rates increased for women aged 35 to 39 and 40 to 44 years. The percentage of all births to unmarried women declined slightly to 40.7% in 2011, from 40.8% in 2010. In 2011, the cesarean delivery rate was unchanged from 2010 at 32.8%. The preterm birth rate declined for the fifth straight year in 2011 to 11.72%; the low birth weight rate declined slightly to 8.10%. The infant mortality rate was 6.05 infant deaths per 1000 live births in 2011, which was not significantly lower than the rate of 6.15 deaths in 2010. Life expectancy at birth was 78.7 years in 2011, which was unchanged from 2010. Crude death rates for children aged 1 to 19 years did not change significantly between 2010 and 2011. Unintentional injuries and homicide were the first and second leading causes of death, respectively, in this age group. These 2 causes of death jointly accounted for 47.0% of all deaths of children and adolescents in 2011.

Differences in definitions and methods of data collection on deaths occurring during or shortly after pregnancy have created confusion and challenges in evaluating research findings. The study aimed to determine if the use of enhanced linkage procedures improve data collection of deaths occurring during or shortly after pregnancy, and how different definitions of those deaths changed the results of data analysis. The study used 2000-2005 Louisiana Pregnancy Mortality Surveillance System (LPMSS) and 2000-2005 death certificates linked with 1999-2005 live birth and fetal death certificates. Five indicators of deaths occurring during or shortly after pregnancy using WHO and CDC/ACOG definitions were estimated. One-sided Spearman rank test was used to analyze maternal mortality trends from 2000 to 2005. Of 345 women who died within 1 year of pregnancy, 187 were identified through linkage; 38 of those were missed by the LPMSS. Total mortality ratios of deaths occurring within 1 year of pregnancy ranged from 13.4 to 88.9 per 100,000 live births depending on the indicator used. CDC/ACOG pregnancy-related death and pregnancy-associated death statistically increased, whereas WHO pregnancy-related death decreased between 2000 and 2005. The most common causes of death differed by indicator. Universal adoption of linkage procedures could improve data on deaths occurring during or shortly after pregnancy. Estimates, trends, and most common causes of death were markedly different depending on which indicator was used. Additionally, the use of different mortality indicators during analysis provides a more detailed picture of potential target areas for future research and interventions.

OBJECTIVE: To estimate mortality ratios for all reported pregnancy deaths in the United States, 1999-2005, and to estimate the effect of the 1999 implementation of International Classification of Diseases, Tenth Revision (ICD-10) and adoption of the U.S. Standard Certificate of Death, 2003 Revision, on the ascertainment of deaths resulting from pregnancy. METHODS: We combined information on pregnancy deaths from the National Vital Statistics System and the Pregnancy Mortality Surveillance System to estimate maternal (during or within 42 days of pregnancy) and pregnancy-related (during or within 1 year of pregnancy) mortality ratios (deaths per 100,000 live births). Data for 1995-1997, 1999-2002, and 2003-2005 were compared in order to estimate the effects of the change to ICD-10 and the inclusion of a pregnancy checkbox on the death certificate. RESULTS: The maternal mortality ratio increased significantly from 11.6 in 1995-1997 to 13.1 for 1999-2002 and 15.3 in 2003-2005; the pregnancy-related mortality ratio increased significantly from 12.6 to 14.7 and 18.1 during the same periods. Vital statistics identified significantly more indirect maternal deaths in 2002-2005 than in 1999-2002. Between 2002 and 2005, mortality ratios increased significantly among 19 states using the revised death certificate with a pregnancy checkbox; ratios did not increase in states without a checkbox. CONCLUSION: Changes in ICD-10 and the 2003 revision of the death certificate increased ascertainment of pregnancy deaths. The changes may also have contributed to misclassification of some deaths as maternal in the vital statistics system. Combining data from both systems estimates higher pregnancy mortality ratios than from either system individually. LEVEL OF EVIDENCE: II.