25 November 2021

Heart problems in kids conceived with ART

Clinical Uncategorised

Experts are calling for early heart checks of children born from assisted reproductive technology, after research shows they have worse left ventricular function and structure. 

Using cardiac ultrasonography, the Chinese study of almost 800 children aged six-10 found that those conceived with ART had significantly higher blood pressure and more left ventricular dysfunction than those who were conceived naturally. 

Children conceived with ART had significantly higher parameters of left ventricular structure, including mean left ventricular mass index, as well as an increased prevalence of left ventricular hypertrophy.

These children were also significantly taller and had a higher BMI than their peers. 

“Abnormal cardiac structure and dysfunction, including an increased risk of left ventricular hypertrophy and left ventricular geometric remodeling, were more frequent among children conceived by ART compared with children in the control group,” the authors wrote in JAMA Network.

The researchers found that these differences were independent of early life factors, current lifestyle factors and regardless of the type of ART used such as ICSI or IVF.

“However, frozen embryo transfer had some favourable cardiac outcomes compared with fresh-embryo transfer, which may be associated with decreased risks of several unfavourable birth outcomes (e.g. being born small for gestational age, low birth weight, and preterm delivery) that are associated with pregnancies conceived from frozen embryo transfer vs fresh embryo transfer,” they said.

An estimated eight million or more children have been born worldwide thanks to assisted reproductive technology, but research has increasingly found a link between these techniques and poorer cardiovascular health of the offspring. The exact mechanism behind these changes is as yet unknown, but it has been suggested the link may pose a health burden in the coming years. 

“There are several potential mechanisms that may explain the association of ART with abnormal LV structure and dysfunction,” the authors wrote. 

They pointed to epigenetic changes in the periconceptional period that may change later cardiovascular development, and may change methylation levels. 

It was also possible that these children encountered more oxidative stress, which could alter cardiac structure and function. Another possible explanation was that assisted reproductive technology was linked to greater problems with lipid and glucose metabolism, and this underpins various cardiovascular diseases. 

“These findings may have significance for clinical and public health,” the authors concluded. “Because childhood is a critical window for early detection, potential intervention, and improvement of cardiac health among children conceived by ART, it may be possible to reverse the unfavourable alterations in their cardiac structure and function.”

JAMA Network 2021, online 4 November