Monozygotic triplet pregnancy following transfer of frozen-thawed embryos.

We report a case of monozygotic triplet pregnancy after the transfer of three frozen-thawed embryos. The outcome of the pregnancy was the birth of three healthy normal boys. The pregnancy was a monochorionic triamniotic triplet pregnancy. This is the first such case of triplets, although it seems that zygote splitting is significantly more common than normal in patients undergoing in-vitro fertilization.