My twins were IVF ICSI and are not identical, during the pregnancy I was sure of this as the embryos had impanted on opposite sides of my uterus and I thought that if one had split then it would implant near the other - would't it.

anyway FYI I read somewhere when I was pregnant that IVF embies have more chance of splitting since they touched more, so I don't think this necessarily means regular or ICSI.

On a funny note, a few ladies in my multiple birth group say they are often asked that question by strangers "are they identical" - boy/girl twins which can't be. I think strangers just don't know what else to say.