OHSU study finds wildfire smoke impacts fertility; Clark County residents included in research

A study published by Oregon Health & Science University in January revealed poor air quality from wildfires can impact the reproductive health of patients living in the Pacific Northwest — including those receiving fertility treatment.

Researchers from OHSU investigated how poor air quality from the 2020 Oregon wildfires affected 69 patients undergoing in-vitro fertilization treatment, including a number from Clark County. Researchers found patients exposed to wildfire smoke during the development phase of treatment created fewer blastocysts, which are embryos that develop from a fertilized egg.

“Part of what makes your IVF cycle successful is often not just having one blastocyst or one embryo for transfer, but having a few,” said Molly Kornfield, lead author and assistant professor of reproductive endocrinology and infertility.

Kornfield said the increase in wildfires due to climate change is a concern across the reproductive health community, especially with 200,000 patients nationally undergoing IVF treatments each year.

“The unfortunate reality is that we are seeing more wildfires because of climate change, so I worry about how this will continue to affect not only patients undergoing fertility treatments, but all individuals who are trying to conceive,” Kornfield said. “I was actually about four weeks pregnant when the (2020) wildfires occurred, and I found myself wondering, what are the reproductive impacts of this really catastrophic air quality going to be on reproduction?”

Researchers conducted a retrospective study of 69 patients who underwent ovarian stimulation and IVF treatment during the six weeks preceding the 2020 wildfires through the 10-day period of unhealthy air quality. Of those patients, 15 were in the laboratory exposure cohort, 16 were in the patient exposure cohort and 44 were unexposed, the study said.

During a normal IVF treatment cycle, patients receive two weeks of hormone injections to stimulate the ovaries to grow eggs. Then, patients undergo egg retrieval, and the eggs are fertilized by sperm to grow into blastocysts. Those blastocysts are either frozen or immediately placed into a patient’s uterus.

According to the study, smoke exposure during the blastocyst phase yielded fewer blastocysts when compared with the control group in which members were not exposed to wildfire. Kornfield said better air filtration may be needed in areas more prone to wildfires, including rural Oregon and certain parts of Washington.

In the future, researchers hope to evaluate the effects of air quality on other reproductive outcomes, including sperm count, miscarriage rates and naturally conceived pregnancies, Kornfield said.