Multiple births

[Julian]

The term multiple births refers to the presence of more than one fetus in the uterus.
The number of twin, triplet, and other multiple births has been increasing during the last two decades. As many as 1 of 30 deliveries involves more than one fetus.
The following make women more likely to become pregnant with more than one fetus:

Taking fertility drugs
Using assisted reproductive techniques (such as in vitro fertilization)
Having had a pregnancy with more than one fetus
Being older
Being of West African descent

[Mark Zuckerberg]

an occasion when more than two babies are born to the same woman at the same time