From twins and quintuplets to octuplets and nonuplets, find out which terms are used for multiple births.
They often wonder how many babies are in quintuplets, sextuplets, nonuplets, and more.
To learn more about multiple birthsincluding how many babies are in quintuplets, sextuplets, and morekeep reading.
Illustration by Hugo Lin
The prefixes for the numbers four through nine come from the Latin words for those numbers.
“Single,” “twin,” and “triplet” come from Middle English.
How Common Are Twin Births?
Between 2019 and 2020 the number dropped 3%.
But the number of twins born from 2020 to 2021 showed a slight increase of 2%.
Researchers note that this small increase occurred among older people who are more likely to useinfertility treatment.
This is due to a change in assisted reproduction treatments, especially the transfer of fewer embryos.
The rates are still three times what they were in the early 1980s, but have been declining.
Due to the splitting of the embryo, identical twins share the same DNA.
This is why they are always the same sex.
Interestingly, sometimes a combination of the above processes occurs.
For example, a person could hyperovulate, releasing multiple eggs during the middle of theirmenstrual cycle.
These eggs are each fertilized by a sperm, and then one or more of these embryo splits.
Multiple Pregnancy.American College of Obstetricians and Gynecologists.
Changes in Twin Births in the United States, 20192021.National Vital Statistics Reports.
Declines in triplet and higher-order multiple births in the United States, 19982014.NCHS Data Brief.2016.
Raising Multiples: Mental Health of Mothers and Fathers in Early Parenthood.Archives of Womens Mental Health.
Identical Twins.National Human Genome Research Institute.
Is the Probability of Having Twins Determined by Genetics?U.S.
National Library of Medicine.
