Determining the quantity of embryos to transfer in an IVF cycle is a crucial decision that needs careful discussion between the patient/couple and the Doctor. The goal of each treatment cycle ought to be the delivery of a full-term , healthy, singleton baby. though transferring more than one embryo can increase the pregnancy rate, at some purpose transferring additional embryos merely serves to increase the multiple pregnancy rate while not altering the pregnancy rate. many European countries have eliminated all discussion of what number embryos to transfer by mandating that every one patients endure solely single-embryo transfers. Whereas elective (or mandatory) single-embryo transfer has been promoted heavily throughout Europe, it's not yet received widespread acceptance within Australia, though this perspective may be changing slowly.

One of the key disadvantages of single-embryo transfer is that it leads to a decreased IVF pregnancy rate from the recent cycle. Proponents of single-embryo transfer claim that the potential reduction within the overall pregnancy rate is well definitely worth the marked reduction in the twin pregnancy rate. Twin pregnancies can be problematic as a result of they're associated with higher rates of preterm labour and preterm delivery. Some couples, however, might want twins or at least regard them as a neutral outcome. This view is very rife among patients who are paying for the treatment themselves (rather than it being coated by insurance) and regard twins as a “two for the value of one” outcome. As noted in Question forty nine, the greatest risk to the health of youngsters following IVF is that the complications associated with prematurity related to multiple births. Despite the risks associated with multiple pregnancy, couples still tell u on a daily basis that they might “love to have twins.”

In Australia, there's no question that the trend is to transfer one embryo in most patients. we fully embrace this idea. In fact, with the recent advances in embryo cryopreservation, like vitrification (see Question 72) frozen-thawed embryos seem to be as likely to implant and turn out healthy pregnancies as embryos transferred in a recent cycle. Thus, within the patients classified as “Most favorable prognosis” we tend to see no have to be compelled to transfer more than one embryo and risk a multiple pregnancy once we can safely perform a frozen-thawed embryo using high-quality vitrified embryos. However, convincing patients has proven more difficult.

The advantages of Natural Cycle IVF is that there's seldom the option to transfer quite one embryo since nearly all patients produce solely a single mature egg in a typical reproductive cycle. Some patients who had planned to undergo single embryo transfer can change their minds at the last minute and elect to transfer two embryos, greatly increasing the chance of a twin pregnancy. With Natural Cycle IVF the temptation to transfer two embryos has been eliminated entirely.

The ASRM has published tips for creating the choice of how many embryos to transfer. Patients who fall into the excellent prognosis class should transfer only 1 or 2 embryos, whereas those with an exceedingly poor prognosis—because of the woman’s age or multiple failed IVFs, for example—may undergo embryo transfer of 5 or more embryos.