Objective: To examine trends in spontaneous abortion-related mortality and
risk factors for these deaths from 1981 through 1991.
Methods: We used national data from the Centers for Disease Control and Pre
vention's Pregnancy Mortality Surveillance System to identify deaths due to
spontaneous abortion (less than 20 weeks' gestation). Case-fatality rates
were defined as the number of spontaneous abortion-related deaths per 100,0
00 spontaneous abortions. We calculated annual case-fatality rates as well
as risk ratios by maternal age, race, and gestational age.
Results: During 1981-1991, a total of 62 spontaneous abortion-related death
s were reported to the Pregnancy Mortality Surveillance System. The overall
case fatality rate was 0.7 per 100,000 spontaneous abortions. Maternal age
35 years and older (risk ratio [RR] 1.7, 95% confidence interval [CI] 0.9-
3.0), maternal race other than white (RR 3.8, 95% CI 2.2-5.9), and gestatio
nal age over 12 weeks (RR 8.0, 95% CI 4.2-11.9) were risk factors for death
due to spontaneous abortion. Of the 62 deaths, 59% were caused by infectio
n, 18% by hemorrhage, 13% by embolism, 5% from complications of anesthesia,
and 5% by other causes. Disseminated intravascular coagulation (DIC) was a
n associated condition among half of those deaths for which it was not the
primary cause of death.
Conclusion: Women 35 years of age and older, of races other than white, and
in the second trimester of pregnancy age are at increased risk of death fr
om spontaneous abortion. In addition, DIC complicates many spontaneous abor
tion cases that end in death. Because spontaneous abortion is a common outc
ome of pregnancy, continued monitoring of spontaneous abortion-related deat
hs is recommended.