Lowest twinning rate (country)

Saudi Arabia registered a rate of 4.9 twins for every 1,000 deliveries in the period 2010–15, according to a study of data from 165 countries by the University of Oxford’s Christiaan Monden and his colleagues, published in 2020. About 1.6 billion twins are now born worldwide each year.

The authors of the report point out that, “The Saudi data come from one single hospital and therefore need to be treated as an estimate with considerable uncertainty. The twin rate may be overestimated if women pregnant with twins are more likely to deliver in this hospital rather than elsewhere compared to women pregnant with a singleton.”