1Demographic characteristics of cases and controls
were compared using t-tests for continuous variables and chi-squared
tests for categorical variables.
2Values are median and inter-quartile range and
exclude missing values
3There were 9 live births with birth weight (g)
< 500. The accepted range for birth weights of live births are
500-6000g.
4Difference in education status is due to a reduced
rate of maternal form completion in fetal death cases as compared to
controls.
5This difference is due to 1) father’s education was
available for all years during the period 1978-2016 from birth
certificates; but father’s education was only available for the years
1978-2003 from fetal death certificates. 2) fathers are less likely
reported in fetal death certificates
Figure S1 . STROBE diagram showing inclusion and exclusion
criteria for relatives of parents of stillbirth cases and controls.