It sounds like the plot of a daytime television show—but could your twins could have different fathers? While it’s extremely rare, it IS possible. Let’s dive into the science behind this phenomenon and see how this rare, yet fascinating situation can occur.
What is it called when twins have different fathers?
Heteropaternal superfecundation might sound scary (or even contagious) but it’s a recognized and documented scientific phenomenon. Superfecundation is when two or more eggs in the same cycle are fertilized by sperm from different men. Heteropaternal superfecundation is when fraternal twins have different fathers, and shows up about once in every 13,000 paternity cases.
How is it possible?
A woman is usually fertile about two weeks before her menstrual cycle begins and for the five days immediately before it begins. Sperm can also remain alive in her body for up to five days after she has sex. If she has sex with multiple partners during this period, it is possible for sperm from different partners to fertilize different eggs in the same cycle, resulting in fraternal twins.
What does it mean for the twins?
Twins with different fathers are still siblings. They still share the same mother. Although it may complicate some aspects of the paternal relationship, that bond between those twins is likely to remain the same. It is up to the families to decide if they need counseling and what sort of relationship the twins will each have with their fathers. It also means that twins can be born that are not only of different sexes and appearance, but even different racial makeups.
Don’t jump to conclusions
Of course, it’s important to remember that just because twins don’t look alike doesn’t mean that they have different fathers. Twins can come from the same father while still differing in appearance. Fraternal twins are also possible with gay couples who both donate sperm to a surrogate, so don’t jump to conclusions every time you see a set of fraternal twins.
While it’s unlikely that your twins have different fathers, it’s not impossible—and it’s always good to have a reliable paternity test to help you resolve any questions about paternity. Order your HomePaternity test today to get the peace of mind and answers you need.