Fracking and Low Birth Weight: Preliminary Evidence

Ted Schettler, MD, MPH
Science Director

In an important development in the debate about health risks associated with fracking for natural gas, Elaine Hill, a doctoral candidate at Cornell University, has carried out a detailed analysis of certain birth outcomes in Pennsylvania, before and after fracking began. She used a “difference-in-difference” study design, which enabled her to compare outcomes in two groups of people:

• Group 1: People living prescribed distances from a location where a well had been permitted but never drilled
• Group 2: People living the same distances from a location where a well had been permitted and subsequently drilled

She compared birth outcomes in groups 1 and 2 before and after any wells were drilled.

The most dramatic finding was a 25% increase in the incidence of low birth weight (LBW) babies in group 2 compared to group 1 after drilling commenced, taking into account other factors that might influence the outcome. To put this in perspective, Hill notes that this increase is much larger than the risk of LBW associated with maternal smoking during pregnancy. Other studies have shown an increased risk of LBW babies with increased levels of air pollution, but the magnitude of this newly-reported effect is striking. LBW has long-term health and economic consequences for individuals, families, communities, and society generally.  Finding contributing causes has long been a public health priority.

Hill’s analysis has not yet undergone peer review and publication.  She chose to present her findings at a recent hearing in NYC since a decision about fracking permits in NY appears to be imminent.  This despite the complete lack of any assessment of the health impact by the NY Department of Environmental Conservation. Nothing. Multiple letters to the Cuomo administration urging that assessment from large coalitions of health professionals and environmental groups have been met with silence.

Read Elaine Hill’s paper