Is it just our imagination, or do more people than ever seem to be having twins?
You’re not imagining things! The rate of double births – both natural twins and IVF twins being born has been increasing for 30 years, and the percentage of children that are a twin is higher than ever. Some experts believe that we’ve reached “Peak Twin”, and we’re experiencing the highest rate of twins in the history of humankind right now.
Natural twins and IVF twins
Some countries produce more twins naturally, due to genetic differences between populations. African and Asian countries produce more dizygotic twins (none-identical) than the rest of the world. Countries with a higher rate of IVF births will naturally show more IVF twins too.
North America has seen the steepest rise in twin births, with a 71% increase, with some places in Europe almost as high. Worldwide the rate has gone from 9 sets of twins per thousand births to 12.
How medically assisted and IVF twins are tipping the balance
Why is this happening? The phenomenon of twins depends on a few different factors. Some of it boils down to luck, with two eggs being released and fertilized at the same time, or one embryo splitting in half and both halves developing. Twins are statistically more likely in older mothers and occur more often in women who have IVF. Some medication to treat infertility can cause women to release more than one egg at a time too, and with global infertility rates rising, more babies than ever are being born after hormonal treatment.
While twins are incredibly cute, it’s healthier to have one baby at a time. Twins can have lower birth weight, a lower rate of survival and more risk of complications for both mothers and babies.
See our IVF portal for lots more articles and resources.