What Is Superfecundation
Superfecundation is a rare phenomenon in which a woman releases multiple eggs during the same ovulation cycle and each egg is fertilized by sperm from separate acts of intercourse. This can result in fraternal twins who have different biological fathers.
Documented Cases of Twins With Different Fathers
Medical literature includes confirmed cases where twins were found to have different fathers through DNA testing. In one widely reported case, a mother of twins learned that each child had a different biological father after a paternity test. Such cases are rare but documented in peer-reviewed studies and legal records.
How Common Is Superfecundation
Exact rates are unclear because most cases are only discovered through paternity testing. Experts estimate that superfecundation occurs in a small fraction of fraternal twin pregnancies. Factors that increase the chance include ovulation of multiple eggs and intercourse with different partners within a short fertile window.
Learn more about multiple ovulation and twin paternity on the National Institutes of Health website.
