Two things to focus on here are air pollutants and heat from climate change. There are many other environmental exposure impacts on women’s health, fertility, pregnancies and in utero exposure, but the systematic review of 68 studies from 2007 to 2019 evaluated the association between ambient heat, air pollution and obstetric outcomes including preterm birth (PTB), low birth weight (LBW), and stillbirth (SB). There were different types of air pollution components and degree of heat exposure, but air pollution was defined as fine particulate matter < 2.5 microns.
In total in all 68 studies, > 32 million U.S. births were analyzed. A total of 57 studies showed a significant association with poor birth outcomes assessing air pollutants in 48 or 58 studies and 9 out of 10 assessing heat exposure. The association of fine particulate air pollutants or ozone was associated with preterm births in 19 of 24 studies and low birth weight in 25 of 29 studies. The data related to still births were limited. The pregnant women at highest risk were asthmatic and minority women, especially African American women throughout the U.S. and Hispanic women living in California. The women with the lowest socioeconomic status and also those living close to power plants and highways had the worst outcomes.
Commentary: As if we did not need more discouraging information about the impact of the crisis of climate change…. but this time, specific to pregnant women and their newborns. There are multiple factors involved in poor obstetrical outcomes, including poverty, nutrition, smoking, alcohol and drug use, select legal prescriptions, violence against the women during pregnancy, and more. But now we have more statistics on the inequities born by minorities and exposure to air pollution and heat exposure during pregnancy, that appears to elevate risks for poor outcomes.
Women and their families and employers and health care providers should do everything possible to meet these additional challenges of pregnant women that affects their risk for preterm births, low birth weight babies and possibly stillbirths. The bigger picture of course, is for more of us to wake up to the climate crisis and the impact it has and will continue to have on our health. What can each of us do to meet this challenge? We could get involved in organizations with the mission to affect policy and change regarding air pollution, water and ground pollution; we could donate to such organizations; we could vote in local, state and federal initiatives and elections that affect policy and values and actions of the politicians. This blog may not sound like a women’s health related topic.. but from pregnancy outcomes to fertility to breast cancer, trust me, it is.
References: Bekkar B, et al. Association of air pollution and heat exposure with preterm birth, low birth weight, and stillbirth in the US: A systematic review. JAMA 2020; June 18.
Guidice L. A clarion warning about pregnancy outcomes and the climate crisis. JAMA Netw Open 2020 June 18.
