superfecundation

So how does superfecundation with multiple fathers happen at all?

The occurrence, known as heteropaternal superfecundation, is rare with only a few cases publicly known worldwide.

That result is rare—so rare that the condition has the improbable name “superfecundation.”

Jennifer Wu, an obstetrician-gynecologist at Lenox Hill Hospital in Manhattan, called it a case of superfecundation, a rare phenomenon classically illustrated in medical textbooks with a black baby and a white baby who are twins.

He explains that heteropaternal superfecundation occurs when a woman gives birth to twins with different biological fathers.