It has been widely demonstrated that air pollution can affect human health and that some pollutant gases can have negative impacts on female fertility rates and cause adverse obstetric outcomes, such as premature birth and low birth weight. Few studies have evaluated the impact of maternal exposure to urban air pollution on the number of female births. To evaluate the association between maternal exposure to air pollution during the year before conception and sex determination. This was a prospective study using low-risk pregnant women living in Sao Paulo, Brazil. The pollutants were measured by a fixed station during a 1-year period before conception. Sex was confirmed after birth. We used multiple logistic regression models to evaluate the association between the pollutants and the sex determination and to estimate the odds ratio (OR) and the 95% confidence interval (CI) of being female based on a quantitative increase in pollutant concentration. We evaluated 371 patients. Elevated exposure to nitrogen dioxide (NO2) and particulate matter lower than 10 μm (PM10) prior to conception were associated with increased odds of being female. Each unit increase of NO2 exposure increased the odds of being female by 8% (OR = 1.08, 95% CI = 1.02, 1.15, p = 0.008), and each unit increase of PM10 increased the odds of being female by 14% (OR = 1.14, 95% CI 1.02 to 1.28, p = 0.021). In Sao Paulo, maternal exposure to pollutants was significantly associated with the odds of being female.

中文翻译：

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圣保罗市母亲受孕前空气污染暴露与性别决定的关系

已经广泛证明，空气污染会影响人类健康，一些污染气体会对女性生育率产生负面影响，并导致不良产科结果，例如早产和低出生体重。很少有研究评估母亲暴露于城市空气污染对女性生育数量的影响。评估受孕前一年母亲暴露于空气污染与性别决定之间的关联。这是一项前瞻性研究，对象是居住在巴西圣保罗的低风险孕妇。污染物是在受孕前 1 年期间由固定站测量的。出生后确认性别。我们使用多元逻辑回归模型来评估污染物与性别决定之间的关联，并根据污染物浓度的定量增加来估计女性的优势比 (OR) 和 95% 置信区间 (CI)。我们评估了 371 名患者。受孕前暴露于二氧化氮 (NO2) 和低于 10 微米 (PM10) 的颗粒物与女性的几率增加有关。NO2 暴露每增加一个单位，成为女性的几率增加 8%（OR = 1.08, 95% CI = 1.02, 1.15, p = 0.008），PM10 每增加一个单位，成为女性的几率增加 14%（OR = 1.14，95% CI 1.02 至 1.28，p = 0.021）。在圣保罗，母亲接触污染物与成为女性的几率显着相关。