Decreased fertility in mice exposed to environmental air pollution in the city of Sao Paulo

Impact of short-term preconceptional exposure to particulate air pollution on treatment outcome in couples undergoing in vitro fertilization and embryo transfer (IVF/ET)

“…We found that no specific subgroup of patients in regard to ovarian response pattern was negatively affected by this exposure, although this observation is limited in some analyses due to the small number of cycles in specific subgroups. A similar observation was found in a previous experimental study that evaluated the effects of chronic exposure to air pollution in a large urban center on the fertility of Balb/c female mice showing that there was no significant difference in the pregnancy rates of mice exposed to clean or polluted air [16].…”

“…In contrast, few studies were able to demonstrate an association between air pollution and fertility impairment in women, probably due to the multiplicity of factors involved in female reproductive function [15][16][17]. Additionally, little is known regarding the impact of preconceptional exposure to metro area ambient air on early embryo development [16].…”

“…Acute preconception exposure to diesel exhaust particles and chronic exposure to fine PM (diameter ≤2.5 µm, PM2.5) present in ambient air were implicated in the disruption of the segregation pattern of the inner cell mass and trophectoderm cell lineages at the blastocyst stage [21,22], an important marker of embryo viability and developmental potential [23]. Defective post-implantation embryonic development resulted in an increased number of implantation failures, decreased number of viable fetuses, and higher rates of miscarriage [14,16]. Recently, a retrospective epidemiological study confirmed the increased risk of early pregnancy loss previously observed in experimental studies in women exposed to particulate air pollution.…”

The relationship between low birth weight and exposure to inhalable particulate matter

“…A series of studies performed by the authors on rodents exposed to ambient levels of air pollution showed both low birth weights and reduced placental weights in animals exposed to air pollution. This and other studies show that it is plausible that placenta underdevelopment plays a role in determining low birth weight outcomes associated with pollution exposure 28,29,30,31 .…”

O impacto da exposição pré-gestacional à poluição atmosférica sobre o processo de implantação embrionária em camundongos

“…As fêmeas de camundongos fêmeas da primeira geração, que cresceram submetidas à poluição ambiental, apresentaram menor número de filhotes nascidos vivos e maior índice de falha no processo de implantação (Mohallem et al, 2005). Porém, para a segunda geração de animais, além dos efeitos já descritos, observou-se redução significativa do peso ao nascer (cerca de 20%) associada a alterações placentárias e um aumento na incidência de perdas pós implantacionais, além de alterações relacionadas aos índices de fertilidade e gestacional, à ciclicidade estral e à reserva folicular de fêmeas nulíparas (Veras et al, 2008;2009e 2010 (Billington 1971;Muntener et al, 1977).…”