A study predicts that nearly 400 million people in 2100 may be alive as a result of assisted reproductive technologies (ART).
The figure, which would account for three percent of the world's projected population, includes not only those conceived using ART, but also their descendants.
'These striking projections offer numbers for the first time instead of what was previously guesswork,' say the authors of the study, published in the journal Reproductive BioMedicine Online. 'Individuals who owe their lives to ART will quietly make a significant contribution to demographic growth as well as social progress.'
The calculations depend on estimates of how many more births a year will occur as a result of improving ART: the figure of 400 million is based on an upper estimate of 30,000 more births a year. Nevertheless, the authors say that they are 'confident in predicting that […] hundreds of millions of people will be alive later in the century whose existence will have depended, one way or other, on reproductive technologies.'
Even if there is no further development in fertility services, nearly 170 million people (1.4 percent of the world's population) alive in 2100 will owe their existence to ART.
Only a minority of these will have been the direct result of assisted conception, with the impact of reproductive technologies on the world's population growing substantially over generations as those individuals have their own children.
Global inequalities in availability of ART (both in terms of location and affordability) could be reduced by increasing prosperity and development of more affordable treatments. Africa is currently the most under-served continent, but a social stigma associated with childlessness means there is potential for substantial expansion in fertility services there if economic conditions improve.
Since the birth of the first IVF baby in 1978, the number of people conceived by reproductive technology has grown much faster than expected: nearly 0.1 percent of the current world's population are believed to have been conceived by ART.