multiple births and ivf in australiaManagement of IVF in Australia is characterised by a very careful approach to embryo transfer, in order to reduce the likelihood of multiple births. Unlike some countries, where transfer of more than six embryos is routine, in Australia generally only one or two embryos are transferred in each attempt.
 Although the world's first IVF baby was born from a natural cycle with spontaneous ovulation, controlled ovarian hyperstimulation is now the norm. Consequently multiple pregnancy has become the hallmark, and it has been estimated that in total, 45% of IVF babies born are from multiple pregnancies, with twinning rate of nearly 25%, triplet rate of 2-3% and quadruplet rate of 0.5% of pregnancies world-wide.
Unfortunately, neonatal and perinatal mortality rates are 3 to 6 times higher for twins when compared to singleton births, and 5 to 15 times for higher order multiples; and the risk of cerebral palsy is six times higher for twins, and twenty times higher for triplets. Multiple pregnancy also places greater physical strain on the mother, with an increased incidence of miscarriage, high blood pressure, bleeding during pregnancy, increased risk of vomiting during pregnancy, and premature birth.
The complication of being born prematurely includes difficulty with breathing, higher incidence of jaundice, and feeding difficulties. Twins also have a higher incidence of congenital abnormality. Triplets are almost always delivered by Caesarean section, and twins far more often.
Even if the babies are born normal, caring for two, three or more babies can be a challenge, with extra emotional, physical and financial stresses.
To reduce the risk of multiple pregnancies we have to limit the number of embryos transferred. Studies now suggest that replacing three embryos does not necessarily result in a higher pregnancy rate, as long as more than two embryos are available to choose from. Excess embryos which are good quality can be frozen, stored, and used in a subsequent cycle if necessary. In deciding how many embryos (or eggs at GIFT), we need to consider the woman's age, the duration of infertility, the reason for the fertility problem, the number of previous attempts, the number of fertilised embryos, and the cleavage stage and quality of embryos replaced.
Rather than deal with a problem of too many embryos implanting needing subsequent selective reduction, it is better to limit the number of embryos transferred. Furthermore, many couples do not want to be placed in the position of such an option due to religious, moral or personal reasons. There is also the risk of losing all the babies, which from large studies, is reported to be up to 10%.
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