Children conceived using assisted reproductive techniques (ART) have a greater risk of congenital heart defects (CHDs) compared with children born through spontaneous conception, according to research.

The meta-analysis of eight studies found that the risk of a CHD increased by 44 percent when the child was conceived using IVF (in vitro fertilisation) or ICSI (intracytoplasmic sperm injection) compared with those conceived without ART.

CHDs were evident in 1.30 percent and 0.68 percent of live births in the ART-conceived group and the spontaneously-conceived group respectively, said the study published in Ultrasound in Obstetrics & Gynaecology.

Dr Paolo Cavoretto, the lead study author, at the IRCCS San Raffaele Hospital in Milan, Italy, said: 'We believe that IVF/ICSI pregnancies present an increased risk of CHDs as a consequence of early placental dysfunction; however, this hypothesis should be demonstrated in future studies.'

He added: 'We recommend fetal echocardiography in all pregnancies from IVF/ICSI.'

The study found that ART did not increase the risk of all cardiac malformations, but only minor CHDs, such as ventricular or atrial septum defects - types of 'holes in the heart'. Dr Katie Morris, a consultant of maternal fetal medicine at the University of Birmingham, noted that the minor CHDs 'would not necessarily be found by a routine scan looking at the baby's heart in detail in the womb'. The research analysed in the study used 'scans to look for heart differences in a variable way, e.g., time, experience of person performing the scan and the detail they looked for'.

She concluded that 'this data, while confirming the increased risk for these pregnancies, does not support a policy in the UK of offering all women conceiving after these techniques a special heart scan (fetal echocardiogram) for their baby', as many minor CHDs would not be detected.

Professor Alastair Sutcliffe, a paediatrician at University College London, suggested that 'the root of all congenital anomalies in ART conception is overbearingly not method, but more why were the couple sub-fertile in the first place'.

The design of the study has also undergone scrutiny. Professor Adam Balen, the chairperson of the British Fertility Society, explained how while the study yielded interesting results, firm conclusions cannot be drawn. 'There could be many reasons for this correlation – for example, people undergoing treatment for infertility are often older – and until all variables can be controlled for, all we can do is say that there might be an association,' he said.

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Reproduced from BioNews with permission, a web- and email-based source of news, information and comment on assisted reproduction and human genetics, published by Progress Educational Trust.