EMBRYO TRANSFER - a vital ingredient in IVF

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Detail RIGHT:

The stage in IVF when the fertilised eggs are transferred to the uterus - see diagram LEFT . The embryologist will load the catheter with the embryos in a tiny drop of culture media.

The catheter is inserted through the cervical canal into the uterus (TOP RIGHT). In many centres this may be under ultrasound imaging to control the precise position before the embryos are expelled in the drop of culture medium against the endometrial lining. Many countries limit the number of embryos transferred to reduce the incidence of multiple pregnancies - some are insisting on the transfer of only one embryo.  The incidence of multiple pregnancies in IVF is causing considerable concern througout the world. Twins impose a risk on the woman carrying the child and pregnancies often result in premature deliveries, low birth weights and associated complications for the children later in life (hearing, developmental difficulties etc.)

Many fertility centres are stressing the need for care and special training in embryo transfer procedures and that pregnancy rates may vary between practitioners which reflect upon their individual skills. A special feature on embryo transfer in a future  these concerns.