Embryo Transfer
Placement of a selected embryo into the uterus as part of assisted fertility treatment
What is embryo transfer?
A frozen embryo transfer places an embryo from an earlier IVF cycle into the womb after it has been thawed. There is no stimulation and no egg collection, so the cycle is far lighter on you than the one that produced the embryos.
Most clinics now freeze all the embryos from a cycle and transfer them later, because a womb that has not just been through stimulation accepts an embryo at least as well, and often better.
One embryo is transferred at a time in most cases. Transferring two raises the chance of twins far more than it raises the chance of a baby, and a twin pregnancy carries real risk for you and for the babies.
What it involves
Your lining is prepared over two to three weeks, either by tracking your natural cycle or with oestrogen tablets or patches followed by progesterone. A scan checks the thickness of the lining before the transfer is booked.
On the day, the embryologist thaws the embryo a few hours beforehand and confirms it has survived. The transfer itself needs no anaesthetic: a speculum is passed, a soft fine catheter is threaded through the cervix under ultrasound guidance, and the embryo is released into the cavity. It takes about ten minutes.
You rest for a short while and go home. Lying flat afterwards makes no difference to the outcome, so there is no need to stay still.
Recovery
You can go back to normal activity the same day, including work and gentle exercise. Continue the progesterone exactly as your clinic prescribes until you are told to stop.
A blood pregnancy test is done about ten to twelve days after the transfer; a home test earlier than that is unreliable and often distressing. Light spotting in that fortnight is common and does not mean the cycle has failed. Contact the clinic for heavy bleeding, severe one-sided pain or fainting, since an ectopic pregnancy needs urgent assessment.
Questions about embryo transfer
Should I transfer one embryo or two?
One, in most situations. Transferring two raises the twin rate sharply while adding relatively little to the chance of taking a baby home. A twin pregnancy carries a much higher risk of premature birth, high blood pressure and neonatal complications. Where your history justifies transferring two, your fertility specialist will explain that reasoning specifically.
Do I need bed rest after the transfer?
No. Studies comparing bed rest with normal activity find no benefit, and some suggest a slightly worse result with prolonged rest. Go back to work, walk, and carry on with gentle exercise. Avoid heavy lifting, very hot baths and vigorous impact sport, and take the progesterone exactly as prescribed.
Is a frozen transfer as good as a fresh one?
For most women it is as good, and for those at risk of ovarian hyperstimulation it is safer, since the transfer happens once the ovaries have settled. Live birth rates per transfer are similar to fresh cycles and depend mainly on the age at which the eggs were collected. Frozen transfers in a medicated cycle carry a slightly higher chance of high blood pressure in pregnancy, which your obstetrician will watch for.
Other fertility & reproductive medicine treatments
Evaluation and treatment of factors that may make it difficult to conceive
Day CareAssessment and treatment of male factors that can affect sperm production, quality or delivery
Day CareTalk to a care coordinator about embryo transfer
Leave a number and a care coordinator calls you back with what the treatment involves and which hospital it would be at. They book a consult only if you want one