More twins are born around the world than ever before, according to a large demographic survey. Twins are born 1 in 42 births.
The study was published today in the journal Human Reproduction and is being conducted in 165 countries. And the inventory showed that in recent years, about 1.6 million twins were born worldwide each year. Since the 1980s, the proportion of twins has increased by a third, from 9 to 12 per 1,000 births.
Researchers believe this may have reached a peak in the number of twins births. In a number of countries, the percentage of twins is no longer increasing, and in some countries it is even decreasing.
Artificial insemination
Researchers compared the numbers of twins births by country for the period 2010-2015 with those for the period 1980 to 1985. Today, more twins are born in Europe and North America. This is mainly due to the frequent use of techniques such as IVF, ICSI, IVF, and ovarian stimulation. All of these techniques increase the chances of twins.
And the researchers found that a relatively large number of twins are also born in Africa, and that hasn’t changed in thirty years. Sociologist Christan Munden, one of the researchers, tells the BBC that there is an explanation. “In Africa, the number of fraternal twins is high. Perhaps this is due to genetic differences between the African population and other populations.”
With the increase in population growth, the number of twins is increasing in Africa and Asia. In those parts of the world, 80% of all twins are now born. Only in South America, in absolute terms, can no increase be seen.
death rate
The study also found that twins’ status is of concern in low or middle income countries per capita. In many African countries, babies lose their twin siblings in the first year of life, according to a previous study conducted in 2017.
Jeroen Smits, professor of economics and human development at Radboud University, participated in both studies. According to him, the information gathered is of great importance. “The death rates of twins in these countries are still very high. Especially in sub-Saharan Africa, many twins lose their twin siblings in the first years of their lives. That’s about three hundred thousand a year.”
Researchers believe that the number of births of twins in India and China, where 36 percent of the world’s population lives, in the coming years, will determine whether the number of twins worldwide continues to rise or fall.