Pnm-19: Residential Exposure to Carbon Monoxide and Spontaneous Abortion

Background: The relationship between air pollution exposure and adverse birth outcomes such as low birth weight and IUGR was studied. However, very few studies evaluated the effect of air pollution emissions on spontaneous abortion. We examined association between spontaneous abortion of the first trimester of pregnancy and ambient concentrations of carbon monoxide in Tehran. Materials and Methods: This study is a case-control research that was conducted on 148 spontaneous abortion (case group) and 148 pregnant women (control group). Samples were collected randomly from 10 hospitals in Tehran between June 2010 to February 2011,and the correlation between spontaneous abortion and carbon monoxide as an environmental pollutant 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 carbon monoxide concentration in case group (4.09 ± 2.09 PPM) was significantly higher than control group (2.81 ± 1/07PPM) in t test (p<0.001), and also the rate of abortion was 1.98 times higher in these areas (CI95% 1.55 - 2.53). For assessing the relationship between gestational age and environmental carbon monoxide concentration linear regression technique was used. Results indicated that there was a negative correlation between these variables. Conclusion: Findings of this study showed that there is a significant relationship between Occurrence of spontaneous abortion and the environmental carbon monoxide concentration. Further research is needed to confirm these results and possibly elucidate the mechanisms responsible for the finding.