Table 1 Effect of air pollutants on spontaneous fertility
From: Does air pollution play a role in infertility?: a systematic review
Publication | Species | Number of subjects | Air pollutant (s) studied | Methodology | Results |
|---|---|---|---|---|---|
Mohallem et al., 2005 [27] | Mice | 104 | Multiple ambient pollutants from automobile traffic | Mice divided into 4 groups maintained in chambers at least 3 months: - Group 1: adults (aged 10 weeks, n = 20) exposed to filtered air - Group 2: adults (n = 20) exposed to ambient air pollutants - Group 3: newborns (aged 10 days, n = 33) exposed to filtered air - Group 4: newborns (n = 31) exposed to ambient air pollutants | No effects of exposure in adulthood. In group 4 compared to group 3, decreased number of newborns per mouse (mean ± range: 4.0 ± 6.0 vs 6.0 ± 7.0; p< 0.04) and increased embryo implantation failure rate (3.5 ± 7.0 vs 2.0 ± 8.0; p < 0.05). |
Veras et al., 2009 [28] | Mice | 60 | Multiple ambient pollutants from automobile traffic | Second-generation mice (age > 60 days) born of couples raised in chamber with filtered air (F) or non-filtered air (NF), divided into 2 categories: - 10 females F and 10 NF used for assessing cycles and ovarian follicles - 40 mated mice divided into 4 groups: - F1: mice raised in F with pregnancy in F - F2: mice raised in F with pregnancy in NF - NF1: mice raised in NF with pregnancy in F - NF2: mice raised in NF with pregnancy in NF | In NF mice compared to F mice: Increased time to mating (mean days (SD): 10.65 (5.77) vs 3.5 (1.54); p < 0.0001) Decreased fertility index (number of pregnant females/total number of females: 55 vs 95%; p < 0.003). Increase in spontaneous abortion rate in NF2 group compared to F1 (mean (SD): 41.7 (5.8) vs 12.1 (5.8); p < 0.005). |
Dejmek et al., 2000 [29] | Humans | 2585 couples | SO2 | Retrospective birth cohort study: Measured average monthly exposure of couples during 4 months before 1st cycle with unprotected intercourse (based on estimated date of conception). | Compared with the reference SO2 exposure level (<40 pg/m3): Adjusted Odd Ratio for fecundability rate: 0.57 (CI, 0.37–0.88) for medium level exposure (40–80 pg/m3): 0.49 (CI 0.29–0.8 1) for high level exposure (>80 pg/m3): |
Slama et al., 2013 [30] | Humans | 1916 couples | SO2, NO2, PM2.5, O3, PAH | Retrospective birth cohort study: Measured average exposure of couples during 2 first months prior to 1st cycle with unprotected intercourse. | Decrease adjusted fecundability ratio (FR [95%CI]) with PM2.5 (0.78 [0.65–0.94]) and NO2 levels (0.72 [0.53–0.97]). |
Nieuwenhuijsen et al., 2014 [31] | Humans | All women of reproductive age (15–44 years) living in Barcelona: mean (SD) 368.92 (±111.22) women per census tract (N = 1061 census tracts) | PM10, PM2.5–10, PM2.5, NO2, NOx | Cross sectional study: Measured average level of exposure of women of reproductive age (15–44 years) living in Barcelona, according to census tract of residence. | Risk ratio [95% CI] for reduced fertility rate (number of live births per 1000 women) = 0.87 [0.82–0.94] per interquartile range of PM2.5–10. |
Mahalingaiah et al., 2016 [32] | Humans | 36,294 nurses of reproductive age | Living in proximity to major roads; PM10, PM2.5–10, PM2.5 | Prospective cohort study: Biannual questionnaire on fertility Residential address proximity to major roads (2 categories: 0–199 m and ≥200 m). Predicted ambient exposure to PM10, PM2.5–10 and PM2.5 at residential address | Hazard Ratio [95% CI] for infertility: 1.11 (CI: 1.02–1.20) for living close to major roads and 1.10 (0.99–1.22) for each 10 mg/m3 increase in cumulative average exposure to PM2.5–10. |