How does this happen that a woman has twins with different fathers?

The mother and her relatives knew that the twins were fraternal and not identical twins, yet suspicion about their drastically different appearance persisted. When the two babies grew into toddlers, the differences in their looks became even more distinct, MSN reports.

One of the twin boys had thin and straight hair, whereas the other baby was reportedly sporting very wavy and thick hair. The presumed father of the boys, a 34-year-old man, decided he and their mother should take them to the Center for Genetic Analysis and Technologies in Hanoi for testing. The parents, particularly the father, were quite shocked when the doctors at the center said the twins were actually only half brothers.

In the case of fraternal twins, the mother released not one but two eggs during the stage of ovulation. The two eggs then spark two distinct and separate fertilization processes to occur. The vast majority of the time, the two eggs are the result of one single incident of intercourse, but not always. If the woman has sex more than once during the week when ovulation occurs, an egg can be produced from more than one intimate encounter. Eggs have a lifespan of about 12 to 48 hours, and sperm can remain viable for fertilization for seven to 10 days.

In the case of the mother of twins from Vietnam, the doctors believe that the woman had sex with more than one partner during the ovulation week and produced an each from both intercourse sessions.

Although having twins who have different dads is very rare, a similar case occurred in the United States last year. A judge in New Jersey determined that two different men should pay child support for a single set of twins. The judge ruled that the twins had different fathers, and each man was legally obligated to pay child support for his biological child.

The term “superfecundation” is also used to describe the incidences where more than one man is the father of twins or other types of multiple births such as triplets. The National Institute of Health (NIH) states that in recent years, up to one in every dozen set of fraternal twins are the result of bi-paternal or superfecundation. A 1997 report by DNA expert Dr. Karl-Hanz Wurzinger states one in every 13,000 reported paternity cases involving twins have different fathers, CNN notes.

Once the twins with different dads story went viral on social media, comments about a decline in morality quickly materialized. While some of the posts targeted the mother of the Vietnamese twins specifically, others were focused on a more broad review of the sexual habits of women around the world.

The NIH report also stated that in America, one in every 400 sets of fraternal twins born to white women is believed to be bi-paternal twins. The statistics of superfecundation are thought to increase in other demographics of women, particularly those who make a living as prostitutes, the health agency notes.

What do you think about the twins having two different dads and the number of similar cases that may now be emerging in the United States?

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