Deciding how many embryos to transfer remains the most difficult decision patients and doctors need to make in an IVF cycle. In a perfect world, if IVF technology ensured a 100% pregnancy rate, everyone would transfer only one embryo, so that all patients would have one baby (actually, many would transfer two so that they could have twins) - and then there would be no need for websites like this one !

Achieving this goal remains the holy grail for IVF doctors , but the technology is still not perfect, and because we cannot regulate the embryo implantation process, we still cannot ensure that each embryo transfer will become a baby.

One easy way of improving the chances of achieving a pregnancy in an IVF cycle is by transferring more embryos. However, as with everything else in life, the price we pay for this is that the risk of having a multiple pregnancy also increases. Obviously, there is a point of diminishing returns, and by transferring more than 2 embryos at a time, one only increases the chances of a high order multiple birth, without increasing the chances of getting pregnant.

The patient's choice

Ideally, patients should be free to choose for themselves how many embryos to transfer - after all, they are the ones who have the most at stake. However, because the burden of caring for high order multiple pregnancies (and the triplets and quadruplets who are born as a result of these) falls on the government, many countries have strictly regulated the numbers of embryos which can be transferred back, and in UK and Australia, doctors are allowed to transfer only 2 embryos. In Scandinavia, doctors transfer only a single embryo.

In our clinic, we advice our patients to transfer only a single blastocyst at a time.

Our rationale is simple - patients want a healthy baby, not just IVF success. There's little point in getting pregnant, and then having handicapped babies , because they were born premature because this was a twin pregnancy !

The rule is simple - Have as many babies as you want - but one at a time !