We’ll explain this side of things in more detail a little further down. Identical twins are less common than fraternal twins – around one third of all twins are identical. If you’re pregnant, your overall chance of having identical twins is about 1 in 250. It’s not always possible to tell if you have identical or fraternal twins while you’re pregnant, although sometimes an ultrasound scan showing the placenta (or placentas) – if it’s performed before 14 weeks pregnant – can offer a strong clue. The most accurate way of determining whether your twins are identical or fraternal is a DNA test, which can be performed after your babies are born. Of course, you might decide this isn’t necessary if your newborn twins look very different from each other.
