IVF Linked to Increased Genetic Mutations in Mouse Study
BOSTON – In a new study published today, researchers at Harvard Medical School have found that in vitro fertilization (IVF) is associated with a significantly higher rate of genetic mutations in mice compared to natural conception. The findings raise questions about the long-term health implications for children conceived via IVF and underscore the need for further research into the potential epigenetic effects of assisted reproductive technologies.
The study, appearing in proceedings of the National Academy of Sciences, revealed that offspring conceived through IVF exhibited approximately twice as many de novo mutations – genetic alterations not inherited from parents – as those conceived naturally. While the research was conducted on mice, the findings have prompted calls for examination into whether similar effects occur in humans, given the increasing prevalence of IVF worldwide. Approximately 10% of all births in the United States each year are now the result of IVF or other assisted reproductive technologies.
Researchers utilized a sophisticated genome sequencing approach to compare the genetic makeup of mice conceived through IVF, intracytoplasmic sperm injection (ICSI), and natural mating. The study focused on mutations arising in the germline – sperm and egg cells – and their transmission to offspring. The increased mutation rate observed in the IVF and ICSI groups was linked to the extended time sperm spend in the laboratory environment before fertilization.
“We found that the longer sperm are held in culture, the more opportunities there are for errors to creep into their DNA,” explained Dr. Karolina Paluszcak,lead author of the study and a researcher in the Department of Genetics at Harvard Medical School. ”This is a critical finding as it suggests that the very process of IVF,while incredibly helpful for many,may come with a previously unrecognized genetic cost.”
The research team emphasized that the observed mutation rate,while statistically significant,does not necessarily translate to a higher risk of disease in IVF-conceived offspring. Though, they caution that the long-term consequences of these mutations are currently unknown. Future research will focus on determining whether similar patterns exist in human IVF cycles and exploring strategies to mitigate the potential for increased genetic errors, such as optimizing sperm culture conditions and shortening the time between egg retrieval and fertilization.
