The Blakes, a couple from Gloucestershire, England, have two children, produced from the same batch of embryos. The children, twins Reuben and Floren, are the products of intracytoplasmic sperm injection, a fertility treatment wherein a a sperm cell is injected into an egg, which is then transferred to the mother’s womb.
As the products of two distinct zygotes (fertilized eggs), Reuben and Floren are dizygotic (“fraternal” or “sororal”) twins, as opposed to monozygotic or identical twins, formed when one zygote splits into two embryos.
The kicker? Reuben is five years older than Floren.
When the Blakes originally got the ICSI treatment, the egg that would eventually become Ms. Blake the younger was frozen and stored, along with four others; Reuben-to-be was implanted in Mrs. Blake’s uterus. The couple took the chance on thawing out the remaining eggs last year, and Floren’s was the only one that survived.
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