Here a current article indicating that it may be very wise to transfer one embryo only in order to increase the chances of falling pregnant:
Implanting two embryos could reduce IVF success
09 January 2017
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Appeared in BioNews 883
Implanting two embryos can reduce IVF success by a quarter if one of the embryos is of poorer quality, new research suggests.
The results of the study, involving 1472 embryos, were presented at the annual conference of the British Fertility Society in Edinburgh last week.
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