Trends and risk factors of stillbirth in New Jersey 1997-2005
ABSTRACT The purpose of this study was to examine the trends in the rates of stillbirth by race and ethnicity and to determine the risk factors of stillbirth.
We used New Jersey data (1997-2005) for live births and fetal deaths. Cox proportional hazards model was used to estimate the risk of stillbirth associated with maternal risk factors and pregnancy complications.
The rate of stillbirth was 4.4/1000 total births (3.4 for white and 7.9 for black non-Hispanics and 4.4 for Hispanics/1000 total births). The rates of stillbirth decreased from 3.8 in 1997 to 2.7/1000 total births in 2005 for white non-Hispanics but remained unchanged for other race/ethnicity groups. Adjusted relative risks for the risk factors associated with stillbirth were 1.3 (95% CI, 1.2-1.4) for maternal age ≥ 35 years, 1.9 (95% CI, 1.7-2.1) for black non-Hispanics, 2.8 (95% CI, 2.4-3.3) for no prenatal care, 40.2 (95% CI, 36.9-43.9) for placental abruption, 5.3 (95% CI, 3.4-8.2) for eclampsia, 3.5 (95% CI, 2.8-4.3) for diabetes mellitus and 1.7 (95% CI, 1.3-2.2) for preeclampsia.
There was a decline in the rate of stillbirth but there were persistent racial disparities with the highest rates of stillbirth for black non-Hispanics.
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ABSTRACT: OBJECTIVE:: We previously reported an increased risk of stillbirth associated with increases in trimester-specific ambient air pollutant concentrations. Here, we consider whether sudden increase in the mean ambient air pollutant concentration immediately before delivery triggers stillbirth. METHODS:: We used New Jersey linked fetal death and hospital discharge data and hourly ambient air pollution measurements from particulate matter ≤2.5 mm (PM2.5), carbon monoxide (CO), nitrogen dioxide (NO2), and sulfur dioxide (SO2) monitors across New Jersey for the years 1998-2004. For each stillbirth, we assigned the concentration of air pollutants from the closest monitoring site within 10 km of the maternal residence. Using a time-stratified case-crossover design and conditional logistic regression, we estimated the relative odds of stillbirth associated with interquartile range (IQR) increases in the mean pollutant concentrations on lag day 2 and lag days 2 through 6 before delivery, and whether these associations were modified by maternal risk factors. RESULTS:: The relative odds of stillbirth increased with IQR increases in the mean concentrations of CO (odds ratio [OR] = 1.20, 95% confidence interval [CI] = 1.05-1.37), SO2 (OR = 1.11, 95% CI = 1.02-1.22), NO2 (OR = 1.11, 95% CI = 0.97-1.26), and PM2.5 (OR = 1.07, 95% CI = 0.93-1.22) 2 days before delivery. We found similar associations with increases in pollutants 2 through 6 days before delivery. These associations were not modified by maternal risk factors. CONCLUSION:: Short-term increases in ambient air pollutant concentrations immediately before delivery may trigger stillbirth.Epidemiology (Cambridge, Mass.) 05/2013; 24(4). DOI:10.1097/EDE.0b013e3182949ce5 · 6.18 Impact Factor
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ABSTRACT: Objective We evaluated risk of subsequent stillbirth (SB) according to gestational age at initial SB.Study Design We retrospectively reviewed a cohort of women delivering a singleton SB with at least one subsequent pregnancy. Relative risks (RRs) were calculated using an initial SB gestational age of 36 to < 40 weeks as the referent. Multivariable logistic regression accounted for potential confounders.Results In all, 2,887 mothers and 5,090 subsequent births met inclusion criteria. For the immediately next pregnancy, the linear trend for gestational age was not significant (RR 0.41; 95% confidence interval [CI] 0.03 to 5.53). However, women with index SBs occurring between 20 and 236/7 weeks' gestation had a RR for subsequent stillbirth of 2.9 (95% CI 1.2 to 7.1). When including subsequent pregnancies, the test for trend for gestational age was nonsignificant (RR 1.5; 95% CI 0.3 to 8.7). However, women suffering a stillbirth between 200/7 and 236/7 weeks' gestation in the index pregnancy had an almost threefold increase in the risk of subsequent stillbirth. Women suffering an index stillbirth between 280/7 and 316/7 weeks' and after 40 weeks' gestation had a 2.5- to 3.5-fold increased risk of subsequent SB.Conclusions Gestational age at initial SB predicts risk of recurrent SB. This effect is most pronounced in women with very preterm or with postterm pregnancies.American Journal of Perinatology 08/2013; 31(5). DOI:10.1055/s-0033-1349344 · 1.60 Impact Factor