Embryo transfer media

Embryo transfer media for improved implantation

In a specialised embryo culture medium used in In Vitro Fertilisation (IVF), a glycoprotein named hyaluronan is employed to help the embryo implant into the uterus.

For pregnancy to occur, the developing embryo must implant into the lining of the uterus (endometrium). Research shows that hyaluronan plays an important role in assisting embryos to implant. Hyaluronan is a naturally occurring substance found in the uterine cavity and fallopian tubes.


Embryo transfer media – treatment procedure

The embryos that are selected for implantation are placed in a small volume of hyaluronan transfer medium. When the transfer procedure takes place, the embryos are loaded into a catheter, along with a tiny amount of the transfer medium, and released into the uterus. Hyaluronan-enriched transfer does not guarantee implantation, but may assist it.

There is some evidence to suggest that females aged over 38 show the most benefit, with a significant increase in pregnancy rates, when a transfer medium with hyaluronan is used (Balaban et al., 2004). There have also been studies indicating embryos that were frozen and thawed may have increased pregnancy rates through the use of a hyaluronan-enriched transfer medium.


Implantation – promoting medium

Hyaluronan appears to aid implantation in several ways:

  • By increasing the cell-to-cell adhesion of the embryo and uterus lining.
  • Interaction with growth factors that facilitate implantation.
  • The by-products of hyaluronan promote angiogenesis – the growth of new blood vessels.
  • Human oocytes and embryos have surface receptors for hyaluronan.
  • Hyaluronan may play a role in preparing the endometrium to be more receptive to embryos for implantation.

The potential fertility improvement that this type of treatment may yield depends on the woman’s age, diagnosis and the initial semen analysis, and should be discussed with your specialist.

City Fertility was one of the first clinics in Australia to introduce embryo transfer media for improved implantation. If you would like to discuss such a procedure as part of your options, please contact the City Fertility scientists or your treating specialist.


Who is a hyaluronan transfer medium recommended for?

  • Women over the age of 38.
  • Women who are using embryos that have been frozen and subsequently thawed for transfer.
  • Women who have failed to achieve a pregnancy despite having good-quality embryos transferred.


What are the potential risks?

There are no known risks associated with the use of a hyaluronan transfer medium.

To learn more, please read our fact sheet: Embryo transfer media.




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