Twins are unique, fascinating and mysterious. But one set of twins is even more unusual than most because they were born almost two years apart.
Little Oliver Best was nearly 2 years old when his baby brother Isaac was born — but despite the age gap, they are technically twins.
How does that happen?
Parents Rachael and Richard Best had been trying to conceive for four years and gone through six unsuccessful rounds of IVF before Rachael fell pregnant. On the seventh cycle, one embryo produced Oliver, who was born in March 2014. Two more embryos were frozen at Leicester Fertility Centre in England, and an eighth cycle of IVF led to baby Isaac.
Other siblings born years apart but considered to be twins because they were conceived from the same batch of embryos during IVF are Reuben and Floren Blake, who were born five years apart, and Jasmine and Simon Billington, who were born an incredible eight years apart.
This is amazing, but how the heck can twins have an eight-year age difference?
After eggs are collected during a treatment cycle and fertilized to create embryos, they could technically be considered twins, triplets, quadruplets, quintuplets, etc. — depending on the number. If all embryos are put back together at the same time and the woman becomes pregnant, she would go on to have a multiples pregnancy.
But if only one embryo is put back in, and the rest frozen and then successfully used at a later date, those babies are twins, albeit twins who don't share a womb and are born at different times.
Yet more proof of how miraculous IVF can be.
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