U. of Bristol-led 'largest study of its kind': Fertility treatment doesn't adversely affect offsprings' cardiovascular health

A groundbreaking international study, led by researchers from the University of Bristol, has found no robust difference in cardiovascular health indicators between children conceived naturally and those conceived using assisted reproductive technologies (ART). 

The findings provide reassurance to parents and individuals undergoing fertility treatments and were published in the European Heart Journal. Concerns about the potential adverse effects of fertility treatment on the long-term cardiovascular health of offspring have persisted since the birth of the first child through in vitro fertilization (IVF). 

Previous studies investigating this subject were limited by small sample sizes, short follow-up periods and inadequate comparison groups. The University of Bristol-led study aimed to address these limitations by utilizing data from the "Children of the '90s" study, a world-leading health study that has been tracking pregnant women and their offspring since 1991. 

The research, conducted by an international team from the Assisted Reproductive Technology and Health (A.R.T-Health) Partnership, examined data from over 35,000 children across Europe, Singapore, and Australia. This large-scale study allowed for a comprehensive analysis of blood pressure, heart rate, lipids, and glucose levels from childhood to young adulthood (up to the early 20s) in individuals conceived through ART.

“This is the largest study of its kind and could not be conducted without data from studies such as 'Children of the '90s,” said Dr. Ahmed Elhakeem, research fellow in epidemiology at Bristol Medical School at the University of Bristol. “Parents conceiving or hoping to conceive through assisted reproductive technology and their offspring should be reassured that cardiometabolic health appears to be comparable in ART-conceived and naturally conceived children. 

"Studies with longer follow-up would be beneficial to examine how results might change across adulthood,” he added.

The results revealed that children conceived using ART showed similar blood pressure, heart rate and glucose levels compared to their naturally conceived peers. The researchers did observe slightly higher cholesterol levels in childhood for those conceived through ART, although this difference did not persist into adulthood. Additionally, there were indications of slightly higher blood pressure in adulthood among the ART-conceived individuals. 

Professor Deborah Lawlor, senior author of the study and professor of epidemiology at Bristol Medical School, emphasized the importance of international collaboration and longitudinal health studies in achieving these research outcomes. She expressed gratitude to the European Research Council, British Heart Foundation, and UK National Institute for Health Research for their support, as well as to the study participants and fellow researchers.

Findings of this study have significant implications for individuals considering or undergoing fertility treatments. With more than 60,000 patients utilizing fertility services in the United Kingdom alone, the reassurance that the heart health of children born through ART is comparable to naturally conceived children brings peace of mind to many families. 

The Human Fertilization and Embryology Authority (HFEA) acknowledged the importance of large-scale studies like this one to drive continuous improvements in care and highlighted its commitment to monitoring the latest research in the field. 

Funding from the European Research Council made this study possible under the European Union's Horizon 2020 research and innovation program, the Medical Research Council (MRC), the British Heart Foundation (BHF), and the National Institute for Health and Care Research Bristol Biomedical Research Centre (NIHR Bristol BRC). 

The collaborative efforts of researchers worldwide have shed light on the long-term effects of fertility treatment on cardiovascular health, contributing to improved understanding and informed decision-making in the field of reproductive medicine.