NRL News

Baby’s first heartbeat is at 16 days, not 21 days, British research finds

by | Oct 12, 2016

By Dave Andrusko

heart34All these years, through all of the fetal development presentations I’ve witnessed, read, watched, or presented, the accepted beginning point for a baby’s first heartbeat was around day 21.

Now a new study published in eLife, a peer-reviewed open access scientific journal, concludes a baby’s first heartbeat is at 16 days.

Our friends at the Society for the Protection of Unborn Children [SPUC] have a very brief, very succinct description of what was found:

A study has demonstrated the earlier beating of the heart in mouse embryos than has previously been thought. When extrapolated to humans, the study suggests that the heart starts beating at 16 days rather than 21.

A team funded by the British Heart Foundation [BHF] at the University of Oxford published their results in the journal eLife. They found that in mice, the heart muscle started to contract as soon as it formed the cardiac crescent–an early stage in heart development–rather than the later stage when the heart appears as a linear tube.

In mice, this crescent appears at 7.5 days after conception, which is equivalent to day 16 in an unborn baby. Scientists hope that this discovery will help in the understanding and treating of congenital heart disease.

Here are some additional details about a discovery that reminds us how very, very early in fetal development milestones occur.

Researchers hope the work will assist both unborn babies and the rest of us.

BHF Professor Paul Riley, who led the research at the University of Oxford, told Mark Prigg of The Daily Mail

‘By finding out how the heart first starts to beat and how problems can arise in heart development, we are one step closer to being able to prevent heart conditions from arising during pregnancy.

‘We also hope that this new research will help us to learn how the beating of new heart muscle cells might be triggered in replaced muscle after a heart attack.’

Professor Sir Nilesh Samani, Medical Director at the British Heart Foundation, which funded the research, added

‘This study describes some of the very first stages in the development of a beating heart, identifies some of the key molecules involved and shows that the initiation of the beat itself has a bearing on the further development of the heart.

‘Such fundamental research is vital in understanding and ultimately preventing diseases that affect the heart.’

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Categories: Fetal Development