Fraternal Twins: Can a Non-Twin Man Have Twins with a Twin Mother?

Yes.

Fraternal (non-identical) twins occur when two separate eggs are released by the ovaries and fertilised by two separate sperm.

The likelihood of fraternal twins is increased if the mother is a twin herself, as she is more likely to release multiple eggs during ovulation.

It is also possible for a man to have fraternal twins with his partner, even if he is not a twin himself. This can happen if he carries a genetic variant that increases the likelihood of his partner releasing multiple eggs.

However, the likelihood of identical twins is not affected by the genetics of either the mother or the father. Identical twins occur when a single egg is fertilised and then splits into two separate embryos.

This process is completely random and there is no way to increase the likelihood of having identical twins.