Birth Outcomes and Maternal Residential Proximity to Natural Gas Development in Rural Colorado

http://dx.doi.org/10.1289/ehp.1306722



Table 2. Association between inverse distance weighted well count within 10-mile radius of maternal residence and CHDs, NTDs, and oral clefts.
Inverse distance weighted well counta 0 wells within 10 miles Low (first tertile) Medium (second tertile) High (third tertile) Cochran–Armitage trend test p-valueb
aFirst tertile, 1–3.62 wells/mile; second tertile, 3.63–125 wells/mile; third tertile, 126–1,400 wells/mile. bPerformed as two-tailed test on unadjusted logistic regression. cAdjusted for maternal age, ethnicity, smoking, alcohol use, education, and elevation of residence, as well as infant parity and sex. dAdjusted only for residence elevation because of low numbers.
Live births (n) 66,626 19,214 19.209 19,793  
CHDs          
Cases (n) 887 281 300 355  
Crude OR 1 1.1 1.2 1.3 < 0.0001
Adjusted OR (95% CI)c   1.1 (0.93, 1.3) 1.2 (1.0, 1.3) 1.3 (1.2, 1.5)  
NTDs          
Cases (n) 27 6 7 19  
Crude OR 1 0.77 0.90 2.4 0.01
Adjusted OR (95% CI)d   0.65 (0.25, 1.7) 0.80 (0.34, 1.9) 2.0 (1.0, 3.9)  
Oral clefts          
Cases (n) 139 31 41 40  
Crude OR 1 0.77 1 0.97 0.9
Adjusted OR (95% CI)c   0.65 (0.43, 0.98) 0.89 (0.61, 1.3) 0.82 (0.55, 1.2)