Replace Fertilised Eggs
IVF Step 6: Replacing the fertilised eggs
This procedure is called an “embryo transfer” or a “blastocyst transfer.”
We will telephone you to let you know when your eggs have fertilised. We will then keep you updated on your embryos’ progress until you come in to have them transferred to your womb.
Embryos are usually transferred to your womb approximately 2-5 days after your egg collection procedure has taken place.
The team will advise you on the best day/stage for your embryo transfer to be carried out, based on how your embryos are developing and information from previous treatment cycles. Blastocysts are simply embryos that have been allowed a little more time to mature in the laboratory. They are the next stage in the growth of the embryo. Blastocysts are usually transferred to your womb approximately five days after your egg collection procedure has taken place.
You will need to keep days 2-5 days after your egg collection procedure free, as we may telephone you on any one of these days to tell you that your embryos are ready to be transferred to your womb. You will need to be prepared to come to the Unit immediately, in case we need to see you very soon. Your partner will need to come with you to the Unit for the embryo transfer. This is because both partners will need to sign the consent form, should you wish to have any spare embryos frozen and stored.
The embryo / blastocyst transfer will be carried out in the same way as the mock embryo transfer that you had before your treatment started. It will be carried out in the treatment room at the IVF Unit. A small plastic tube will be threaded into your womb via the natural opening in your cervix. This tube will be used to gently place the embryos/blastocysts in your womb. The embryo/blastocyst transfer is usually quick and painless.
By law, there is a limit to the number of embryos/blastocysts that can be transferred to your womb at any one time. This is because there is a risk of multiple pregnancy (twins, triplets, etc.) if more than one embryo/blastocyst is transferred. Although the idea of having twins or triplets may sound good to you, it has to be remembered that multiple pregnancy carries many serious health risks to both the mother and the babies, including an increased risk of losing the pregnancy (miscarriage).
The Hull IVF Unit has a single embryo transfer policy and will only replace a single embryo in women whose chances of successful treatment are good, thus reducing the risk of multiple pregnancies. Each case is decided on an individual basis. We are permitted to transfer a maximum of three embryos in women over 40, but only in exceptional circumstances.
After your embryo/blastocyst transfer has taken place you will walk back to the recovery room to get ready for home. You will be given clear, written information on what you should do next. This information will include:
- How long you should continue to use the progesterone cream/pessaries for (see step 4).
- How long you should wait before you do a pregnancy test.
It is important that you follow these instructions carefully. If you carry out the pregnancy test too early, it may give a false positive result. This occurs when the test says that you are pregnant, when you are not. This happens because the drugs used during the treatment cycle will still be in your body. These drugs are detected by the pregnancy test as a false “pregnancy.” A false positive result would be extremely distressing, which is why we ask patients to wait.
You will need to take it easy after your embryo/blastocyst transfer. We advise patients to rest completely for the rest of the day and avoid stressful situations for the next two weeks. This may mean that you have to take time off work, if you find your job particularly stressful.
It will not be necessary for you to remain lying down after the procedure. Lying down for a long period of time will not increase the chance of the embryo/blastocyst implanting in your womb. You can also use the toilet as normal, as the embryos will not be affected.
Storing spare embryos/blastocysts
Spare embryos and blastocysts can be frozen and stored for use in future treatment cycles.
This will make future treatment cycles easier and cheaper, as it will mean fewer injections and no egg collection procedure.
However, freezing spare embryos or blastocysts for storage is not a suitable option for everyone. The freezing and thawing out process is very tough on embryos and blastocysts and some do not survive. The embryos and blastocysts have to be of the very best quality if they are to have any chance of surviving freezing and thawing.
Your best embryo or blastocyst will be the one selected to be transferred to your womb, so it is likely that any spares will be of a poorer quality. It is for this reason that we do not recommend storage to all our patients.
An embryologist will talk to you before you have your embryo/blastocyst transferred, to discuss whether or not your embryos/blastocysts would be suitable for freezing. Both partners will need to come to the embryo/blastocyst transfer, as you will both be required to sign the consent form before storage can take place.
The consent form will cover issues such as what the Unit should do with the embryos in the unfortunate event of one partner dying or becoming incapacitated. Either partner can change their mind and withdraw their consent at any time.
The Unit will only be allowed to store your embryos for the period of time agreed on the consent form. We will contact you on an annual basis and again when you are nearing the end of your agreed storage period to ask you what you would like us to do next. If we cannot contact you, we will be forced to take your embryos out of storage and allow them to degenerate (break down). It is for this reason that you must keep us up to date if you change your contact details.
If you choose to have another cycle of treatment with your stored embryos, this will be known as a “frozen embryo transfer,” or FET for short. For more information about frozen embryo transfers, please refer to our patient information booklet.
Page Last Modified: 23rd February 2017