Pnm-20: The Impact of Aromatic Hydrocarbons and Particulate Matter on Spontaneous Abortion

Background: Epidemiological evidence suggests that fine particulate air pollution, particularly particles less than 10 microns in diameter (PM10) exposure adversely affects pregnancy outcomes and usually aromatic hydrocarbons such as benzene bound to fine particles. We evaluated the impacts of PM10 and benzene on spontaneous abortion of first trimester of pregnancy in Tehran. Materials and Methods: We conducted a case-control study in Tehran between June 2010 and February 2011. Cases were 148 women with under 14 weeks spontaneous abortion and control were 148 pregnant women more than 14 weeks of gestation matched to cases. Samples were collected randomly from 10 hospitals in Tehran. the correlation between spontaneous abortion and PM10 and benzene as environmental pollutants was investigated. Results: There were no significant difference in age, their husbands&#039; age, age at the first childbirth, educational level, previous delivery type and the interval between deliveries, experience of any previous abortion, body mass index, parity, average income of the family, duration of residence in Tehran and the amount of time spent at work and outside of the home between the two groups (p>0.05). The mean of environmental PM10 concentration in case group (94.4 ± 39.22 micro g/m3) was significantly higher than control group (83.54 ± 22.55 micro g/m3) in t test (p<0.001), the odds ratio of spontaneous abortion in the areas with higher concentration of PM10 was 1.01 (CI 95% 1.00 - 1.018). linear regression technique indicated that there was a negative correlation between environmental PM10 concentration and gestational age (p<0.05). For assessing the relationship between environmental benzene concentration and spontaneous abortion Spearman’s correlation coefficient was used. Results showed that there was no significant correlation between these variables (p=0.07). Conclusion: Pregnant women exposed to environmental PM10 may be at increased risk of spontaneous abortion. Further research is needed to confirm these results and possibly elucidate the mechanisms responsible for the finding.