The association between air pollution and preterm birth and low birth weight in Guangdong, China

BMC Public Health

Table 5 Associations between preterm birth and pregnancy exposure to air pollutions during each month

	The first month	The second month	The third month	The fourth month	The fifth month	The sixth month	The seventh month	The eighth month	The ninth month	The tenth month
PM_2.5
OR	1.006	1.038^a	1.001	0.991	1.002	0.995	1.010	1.028^a	0.992	1.021
95% CI	0.99~1.01	1.01~1.07	0.98~1.02	0.97~1.01	0.98~1.02	0.98~1.01	0.99~1.03	1.01~1.05	0.97~1.01	0.99~1.04
PM₁₀
OR	1.006	1.021^a	0.993	0.989	1.000	0.999	1.007	1.012^a	0.990	1.008
95% CI	0.98~1.02	1.01~1.04	0.99~1.01	0.97~1.00	0.99~1.01	0.99~1.01	0.99~1.02	1.00~1.02	0.98~1.00	0.99~1.02
SO₂
OR	1.052	1.018	.920^a	1.002	1.035	0.998	0.987	1.019	0.995	1.033
95% CI	0.99~1.12	0.97~1.07	0.88~0.96	0.95~1.05	0.98~1.09	0.95~1.05	0.94~1.03	0.98~1.06	0.96~1.04	0.99~1.07
NO₂
OR	1.032	1.043^a	0.962^a	1.010	1.013	1.016	0.986	1.021	1.000	1.034^a
95% CI	0.99~1.08	1.01~1.08	0.93~0.99	0.97~1.05	0.98~1.06	0.98~1.05	0.95~1.02	0.98~1.06	0.97~1.03	1.00~1.07
CO
OR	1.905^a	1.069^a	0.970	0.906^a	0.887	0.902^a	0.924	0.971	0.990	1.001
95% CI	1.02~1.17	1.001~1.14	0.91~1.04	0.84~0.98	0.81~0.97	0.84~0.97	0.87~0.98	0.91~1.03	0.931~1.05	0.93~1.08
O₃
OR	1.004	1.000	0.999	0.934	1.006	0.958	1.023	1.103^a	0.987	1.007
95% CI	0.93~1.09	0.99~1.00	0.99~1.00	0.86~1.01	0.94~1.08	0.90~1.01	0.96~1.08	1.03~1.18	0.89~1.04	0.99~1.02

ISSN: 1471-2458