Transfer one or two embryos: what does it depend on?
The transfer of more than one embryo in IVF treatment is based on clinical judgment and the woman’s age
Embryo transfer is the final step in an IVF treatment. Once the eggs have been inseminated in the laboratory and the embryos have been generated, it is time to introduce them into the future mum’s womb. At this point, and in the event of having more than one embryo suitable for transfer, many women are gripped by a doubt: “What is better, to transfer one embryo or two?”.
Up to three embryos
According to the law, in Spain it is possible to transfer up to three embryos during IVF treatment. However, this option is generally recommended only for women over 40 who undergo IVF with their own eggs. In these cases, their eggs are of lower quality, so the chances of a multiple pregnancy, which is considered risky for both mum and baby, are very remote.
The decision will depend on medical opinion, which is mainly based on the woman’s age. When the medical team recommends that the future mother should transfer more than one embryo, the aim is to increase her chances of getting pregnant, and never the option of achieving a twin pregnancy.
As Dr. María Jesús López, a specialist in assisted reproduction at Eugin Clinic explains, “all pregnancies involve certain risks, but in twins the risks increase, so each case must be assessed before embryo transfer.”
While monitoring a twin pregnancy is now completely feasible from a medical point of view, Dr. Lopez says that “a singleton pregnancy is still the ideal option”. “In any case – she points out – once the woman’s medical history is known, the doctor will recommend the number of embryos to be transferred according to her case.” If there are no medical contraindications for a twin pregnancy, the woman will decide, along with her partner if she has one, whether to transfer one or more embryos.
Age, the key factor
It should not be forgotten that in assisted reproduction treatment, the chances of success don’t just depend on the number of embryos transferred, but mainly on the quality of the eggs. In cases of undergoing treatment with one’s own eggs, the woman’s age will be a determining factor in the outcome.