Twins can have different fathers: Strange but true

My friend Dr Munialo works in one of the hospitals along the upcoming Mombasa-Nairobi standard gauge railway (SGR) being constructed by Chinese firms.

He shared with me a recent encounter where he delivered a set of twins who clearly looked very different.

Nduku Sammy, the expectant woman, had for the last year worked as a tea-girl at one of the construction sites, while her husband Sammy Mutua was a machine operator at the same project.

The mother of two had been known to have twin gestation and a cesarean section was planned for the delivery.

On D-day, Nduku was put under regional anaesthesia which is a procedure where the mother remains awake and is able to see the babies immediately they are born.

When the first twin was delivered, Nduku, heaved a sigh of relief saying "Huyu ni wa Sammy" (This one belongs to Sammy). What happened next left everyone in shock.

The second twin was born with very distinct Oriental features and the mother exclaimed loudly "Haka ni ka mChinese! Leo Sammy amenipata, tafadhali munisaidie ... Sammy ataniuwa" (This one belongs to the Chinese. Today Sammy has caught me please help me, Sammy will kill me.)

That was the beginning of a long confession to the theatre staff as the operation went on. Nduku confirmed she had been having an illicit affair with one of her Chinese bosses and that she had denied the same when confronted by her husband who apparently now had irrefutable proof.

She confessed to having sex with her husband and her Chinese friend three days apart. But when the pregnancy came she never imagined it would reveal her secrets.

We all know that siblings can have different fathers but what about twins? It does happen. In fact, one study estimates that as many as 1 in 400 sets of fraternal twins is "bipaternal."

How is it possible? Simple: Two eggs from the same mother get fertilised by two different fathers within the same ovulation period.

This is called super-fecundation which happens when twins are conceived days apart, within the same fertility window, and they could be from the same or different fathers.

A word to the wise: If you know twins who look nothing alike, do not assume they have separate fathers. It is also not uncommon to have twins who even appear to be of different races.