Last month, Dr. Shruti Mahalingaiah from the Boston University School of Medicine, along with other scholars published a study that examined the effects of exposure to air pollution on infertility. Researchers studied a sample of over 36,000 female nurses in the United States between 1989 and 2003. They found that women who lived within 199 meters of a major road were more likely to experience infertility. The study measured both primary and secondary infertility, where the former refers to women trying to conceive for at least a year without success and the latter refers to couples who cannot conceive after at least one prior pregnancy. Though there was no significant impact of air pollution on primary infertility, women who lived near major roads were 21% more likely to report secondary infertility compared to those who lived farther away. The infertility effects were stronger for those who experienced chronic exposure to air pollution rather than short-term exposure.
Dr. Mahalingaiah indicated that the risks are small at an individual level. However, Mark Nieuwenhuijsen, a researcher at the Center for Research in Environmental Epidemiology and the Barcelona Institute for Global Health, told Reuters the finding could have a societal impact if a large number of women are exposed to air pollution. Given that a large number of major Indian cities, especially north Indian cities, are among the most polluted in the world, there could be large-scale infertility impacts seen here. However, the U.S. study is one of the first of its kind for tracking air pollution and infertility outcomes over a long-term period, and similar research is yet to be done in India.
Though infertility research is limited here, some work has been done on the impact of air pollution on the health of newborns. In 2014, scholars associated birth delivery data with nearby air pollution quality in Delhi for over 10,500 birth records. The study suggested that dangerous gases commonly found in polluted air could affect the health of newly born babies, leading to weight complications or premature death. Though more robust studies are required to show causation rather than correlation, another previous study by Fleischer et al. conducted across 22 countries suggests that air pollution may lead to low birth weights among babies, but not necessarily premature birth unless air pollution levels are extremely high. The bad news is that air pollution levels are, in fact, extremely high in most Indian cities, which could increase the number of preterm births; India already has the highest number of premature births globally. Other studies conducted outside of India confirm findings on low birth weight and in some cases, high infant or perinatal mortality.
Overall, there is a wealth of evidence (much of which we haven’t listed here) which suggests negative effects of air pollution on fertility and perinatal or infant health. Though many of these studies need to be replicated in India, it’s likely that the effects will be no different here. In order to reduce negative health outcomes of air pollution, doctors suggest limiting outdoor activity and physical activity when possible. For cleaner air indoors, try one of our air filters!