Veterinary surgeon Ross Allan said that if Molly was left untreated then she risked developing a long-term debilitating condition.
But whatever the surgical choice, intersexuals show us that gender is infinitely more complex than shape of our genitals.
Her owners Mary, 56, and Frank Finlay, 63, from Glasgow, said despite the surgery, Molly is the same little dog they adopted 18 months ago.
From the moment of birth, everybody wants to know is it a boy or a girl?
And the 'terrifying' animal - whose scientific name is Bathysaurus ferox - is also a hermaphrodite, meaning it has both male and female reproductive organs.
Scientists believe the lizard fish has evolved to have reproductive tissue to maximize its chances of reproduction in the deep sea, where animals typically live further apart.