April 4, 2022

Study finds link between high density of fracking operations and increased risk of adverse birth outcomes

UCalgary multidisciplinary team investigating the relationship between maternal and child health and hydraulic fracturing in Alberta

Calgary, AB – A multidisciplinary team of researchers with expertise in medicine, education, engineering, geography, science, and law is investigating maternal and child health, child development, regulations and policy related to hydraulic fracturing in Alberta. Commonly called fracking, this is a type of unconventional oil and gas production that involves the use of directional drilling and the injection of large amounts of fluid into wells to facilitate the extraction of natural gas and oil. In Alberta, there are over 150,000 active wells located around the province. The process of fracking occurs over a short period over the lifetime of a well.

In the first study the University of Calgary team has published in this research area; the scientists discovered a link between the density of fracking operations and increased risk for poor health outcomes for pregnant people and their babies.  

“There is very little research about fracking as it relates to the health of pregnant people and children living near these sites. Our study found the rate of spontaneous pre-term deliveries – birth before 37 weeks – increased significantly relative to the number of fracturing sites within 10 kilometres of their home.”

- Amy Metcalfe, PhD, co-principal investigator and associate professor at the Cumming School of Medicine

Those living near one to 24 well sites had a 7.4 per cent risk of pre-term delivery, and this risk rose to 11.4 per cent for those living near 100 or more hydraulicly fractured oil or gas operations.

“Pre-term infants are at higher risk of developing neurodevelopmental difficulties, physical disabilities, and behaviour problems, including autism, cerebral palsy and epilepsy,” says Metcalfe.

Researchers reviewed health data of reproductive age females (18-to-50) over a five-year period (2013-2018). They looked specifically at those living in rural areas whose homes were near fracking sites. Results are published in JAMA Pediatrics.

“We found risk to maternal and child health increased with the density of fracked well sites close to the home versus the distance from the well site. In this study, data showed the risk of being born small for gestational age jumped from eight per cent for those exposed to one to 24 wells to 12.6 per cent for those exposed to 100 or more wells.”

- Carly McMorris, PhD, co-principal investigator and associate professor at the Werklund School of Education

Being born too early or small can have long-lasting health and developmental impacts for children and has also been shown to be a strong predictor of later cardiovascular disease in mothers. McMorris is currently recruiting participants for a study to better understand whether hydraulic fracturing impacts child development.

The researchers will assess thinking skills, academic abilities and social-emotional functioning in children in grades one-through-three living in a community close to and remote from fracking operations. The communities selected are Grande Prairie and Lethbridge. The children will also wear a device that will test air pollution around them, for one week.

Researchers say the results from these studies will provide evidence that could help inform decisions and practices related to fracking. Current legislation in Alberta requires that sites be at least 100 metres away from residential locations.

The study is supported by the New Frontiers in Research Fund administered by the Tri-Agency Institutional Programs Secretariate on behalf of Canada’s three federal research funding agencies: Social Sciences and Humanities Research Council (SSHRC), the Canadian Institutes of Health Research (CIHR) and the Natural Sciences and Engineering Research Council (NSERC).

The other members of the team are first author Zoe F. Cairncross, MPH, Isabelle Couloigner, PhD, Faculty of Arts, Cathryn Ryan, PhD, Faculty of Science, Lucija Muehlenbachs, PhD, Faculty of Arts, Nickie Nikolaou, LLM, Faculty of Law, Ron Chik-Kwong Wong, PhD, Schulich School of Engineering, Selwynne M. Hawkins, BSc, Faculty of Law, Stefania Bertazzon, PhD, Faculty of Arts, and Jason Cabaj, MD, Cumming School of Medicine.

Child Health and Wellness
The University of Calgary is driving science and innovation to transform the health and wellbeing of children and families. Led by the Alberta Children’s Hospital Research Institute, top scientists across the campus are partnering with Alberta Health Services, the Alberta Children’s Hospital Foundation, and our community to create a better future for children through research.


Amy Metcalfe, PhD, is an associate professor in the departments of Obstetrics & Gynaecology, Community Health Sciences, and Medicine at the Cumming School of Medicine (CSM) and a member of the Alberta Children’s Hospital Research Institute (ACHRI), the Libin Cardiovascular Institute, the Owerko Centre, and the O’Brien Institute for Public Health (OIPH) at the CSM.

Carly McMorris, PhD, is a child clinical psychologist and an associate professor at the Werklund School of Education and an adjunct associate professor in the departments of
Psychology at the Faculty of Arts, and Paediatrics and Psychiatry at the CSM. She is also a member of ACHRI, the Owerko Centre, the Hotchkiss Brain Institute, The Mathison Centre for Mental Health Research & Education, and OIPH at the CSM.

Media inquiries

Clayton MacGillivray
Content and Media Specialist
Werklund School of Education
University of Calgary

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