What Causes Twins?

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When a fertilized egg splits into two, both cells start to develop in the normal way. They get implanted in the womb close together and as a result, two babies or twins are developed. Twins can be identical or non-identical. Identical twins occur when a single fertilized egg splits into two. They are of the same sex and share the same features, such as hair colour, height and look very much alike. Both share the same placenta. Non-identical twins are the result of two separate eggs being fertilized at the same time. They are nourished by separate placentas. They may or may not be of the same sex and bear not much similarities.

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