Association between air pollutants and neural tube defects during pregnancy in Lanzhou, China: a time series analysis

Association between preconception and early pregnancy exposure to fine particulate matter and neural tube defects: A nested case-control study

“…9,14,15 A matched case-control study conducted in Lebanon from 2014 to 2017 involving 553 cases and 10,214 controls indicated that a 1 µg/m 3 increase in PM 2.5 concentration was associated with a 10% increase in the risk of NTDs at gestational weeks 2-7. 7 Conversely, studies performed in California (San Joaquin Valley) 10,11,16 , Massachusetts 8 , Texas 17 , North Carolina 18 , England 23 , Barcelona 19 , Lanzhou 20 , and Xi'an 13 found negative or no associations between preconception or early pregnancy exposure to PM 10 /PM 2.5 and NTDs. The discrepancy between studies may be due to differences in exposure levels to PM 2.5 , outcome de nition, race, exposure assessment approaches, and duration of exposure.…”

“…9,14,15 In addition, a case-control study performed in Lebanon from 2014 to 2017 reported that each 1 µg/m 3 increase in PM 2.5 was associated with a 10% increase in the risk of NTDs at gestational weeks 2-7. 7 Studies in California, 10,11,16 Massachusetts, 8 Texas, 17 North Carolina, 18 Barcelona, 19 Lanzhou, 20 and Xi'an 13 found negative or no associations between preconception and early pregnancy exposure to PM 10 /PM 2.5 and NTDs. These con icting results may be explained by differences in the de nition of NTDs, study design (cohort/case-control/time series), PM 2.5 concentration, duration of exposure, folic acid intake, and consumption of forti ed foods.…”