Traditional observations of embryos during an IVF procedure give a glimpse into the development of the human embryo as it develops from a single cell to a blastocyst five days after egg collection. This involves bringing the embryos out of the incubator, so that they can be assessed under the microscope, which could theoretically be stressful for the embryos because of the change of environmental conditions.
To minimise the disturbance and stress to the embryos, microscopic observations are usually carried out once a day or every other day, to assess the morphology (form, shape, appearance and developmental stage) of the embryos. This means that there is a potential of missing significant events during embryo development while they are in the incubator not being observed. Since embryo morphology is the primary way in which embryos are selected for transfer there is a dilemma in how to get the most information from the observations without repeatedly removing the embryos from the incubator.
In contrast to traditional morphology assessment, time-lapse technology uses a camera system placed within an incubator to take an image of the embryos every five or ten minutes without removing them from the incubator. These images can then be combined together to make a video clip which can be studied remotely on a computer screen to assess the “continuously” changing morphology of the embryos, without having to take them out of the incubator. This also allows the embryologists to spot any abnormal development of embryos which may be missed by conventional assessment. This gives more information and helps the embryologists to choose the best embryo(s) for transfer without causing any additional environmental stress to the embryos.
The time-lapse imaging system avoids the need to move embryos or unnecessarily expose them to light from conventional examination with a traditional microscope. During the time-lapse culture embryos are also cultured in specially designed dishes which can hold either 9 or 16 embryos. The dish also allows the embryos to be cultured under ‘group’ culture conditions i.e. within the same droplet of culture medium, whilst also keeping the embryos in place so that they can be monitored continuously. Group culture has been shown to be beneficial to embryo development.
It is important to remember that there are still relatively few robust research studies which show that time-lapse imaging will increase the chance of success. However the initial data from studies are promising and support the idea that embryo selection or de-selection can be improved using time-lapse technology, and that embryo culture can be improved in an undisturbed environment. Both of these factors are important in improving the chance of success in IVF procedures.
Transferring more embryos to maximise the chance of pregnancy frequently results in multiple births, which is a risk for both mother and child. With the increased information from time-lapse imaging of embryo development and subsequent detailed analysis the embryologists can more confidently select the best embryos for transfer, significantly improving the chance of a successful single-embryo transfer.
All BMI Fertility Centres can offer this technology at an additional charge. We believe the use of this technology is currently best suited to patients who have a number of embryos to choose between.
What will this mean? What do I need to do?
If you are interested in using time-lapse imaging at your centre please inform the nurse or consultant during your initial consultations. If you require additional information please contact your local centre directly who will be able to advise you further.
Read more about the risk of fertility treatments and welfare of the child.