Step 4: Embryo Transfer

Embryo transfer is the final step in the IVF process.  By this point, the recipient has undergone extensive hormone therapy to prepare her uterus for implantation.  When the eggs have been fertilized, the resulting embryos are placed in the recipient's uterus.  Typically, multiple embryos (two to four) are transferred in order to increase the chances of one of them implanting into the uterus.

Timing of Embryo Transfer

An embryologist will work with a couple and their physician in order to time the embryo transfer to increase the chances of pregnancy.  The transfer of embryos can occur between one and five days after fertilization, depending on factors such as low sperm count and embryo development.  Same-day embryo transfer, in which embryos are transferred about four hours after retrieval, is becoming more common, since it allows recipients to undergo treatment on an outpatient basis.

Activated Oocyte Transfer (AOT)

Another option is Activated Oocyte Transfer (AOT), in which the embryos are transferred to the uterus about one hour after they are fertilized.  According to a study reported by the Oxford University Press, the AOT procedure may be more effective than others when the male has an extremely low sperm count.

The Embryo Transfer Procedure

The embryo transfer procedure, which is much like a pap smear, is usually painless and does not require anesthesia.  The embryos are placed in a small amount of fluid, which is then placed in a thin tube (catheter) and passed into the uterus through the cervix.  While the procedure is usually successful, it is possible for the embryos to be displaced in the cervix (resulting in loss of the embryos) or in the fallopian tubes (potentially resulting in ectopic pregnancy).  The procedure may cause mild bleeding and/or cramping.  The recipient can return home shortly after the procedure and should relax for the rest of the day.

Locate an Infertility Expert

For more information on infertility treatments and embryo transfer, you should locate a skilled infertility specialist in your area.  Talented experts can guide you through the decisions involved in embryo transfer and assure that your experience is as stress-free and successful as possible.