Day 0 - Your egg collection

Day 0 - Your egg collection

The morning

On the morning of your egg collection you’ll arrive at Cambridge IVF and be admitted to our ward area ready for your trip to theatre.  While you are having your eggs collected we’ll be preparing the sperm sample from your partner or donor which will be used to inseminate your eggs later in the day. 

We use a microscope to identify the eggs which are surrounded by a cloud of cells called cumulus from the fluid the doctor collects from your follicles.  We then wash the eggs and place them in the incubator in a culture medium which is designed to give them the nutrients they need until we are ready to inseminate the eggs the same afternoon.

After egg collection

After your egg collection a member of our laboratory team will come and see you and confirm with you the number of eggs we collected, the quality of the semen sample and the insemination method we intend to use (IVF, ICSI or IMSI) to fertilise your eggs.

Before your treatment starts, your semen will have been analysed. If you’re using a donor, we’ll have the information we need from them too. Based on this, we’ll already have a good idea what the best treatment option is. Sometimes things can change on the day, so we’re always flexible in our approach. We want to ensure that you get the very best chance of a successful outcome from your treatment cycle.

We’ll also let you know the arrangements for the next few days and what contact we will be making with you and when.

What we do next will depend on your treatment

  • If you’re using standard IVF, we’ll mix the prepared sperm sample with the eggs in a petri dish.  This process is controlled using our electronic witnessing system which prevents errors occurring in the lab.  It won’t let us use any sperm with your eggs except the one we’ve prepared for you. The procedure is fast and within five minutes your eggs are back in the incubator and the fertilization process has begun to take place.
  • ICSI takes the insemination process a little further. Here we inject a single sperm into each mature egg using a very fine pipette.  We carry out this procedure when we believe that there is a significant chance that the sperm and eggs may not fertilise well using the IVF technique. Following the injection procedure the eggs we return your eggs to the incubator overnight.
  • IMSI takes ICSI to the next level. During IMSI, we use a very high power microscope to magnify the sperm around 7000 times.  This allows us to see in great detail how the sperm looks and to select the most perfect sperm for the ICSI procedure.  IMSI is a very new development and is showing promise in other UK clinics for a specific group of patients. If we feel you are going to benefit from IMSI we will have discussed this with you.  Once the best sperm has been selected the IMSI procedure is carried out in exactly the same way to the ICSI.

We can only perform ICSI and IMSI on mature eggs – we can easily spot an egg which is mature using the microscope.  Immature eggs wouldn’t fertilize and it’s actually illegal for us to inject them.  It’s not unusual for some of your eggs to be immature, so you need to be prepared for this when we call and let you know how the fertilisation procedure has gone.

On average we would expect approximately 65% of all injected eggs to fertilise normally from ICSI and IMSI.  The average may be lower if you are using sperm which has been recovered surgically or if we know your egg quality is variable.

You now face a wait of up to five days. For you these are very tense days of waiting and not being able to do anything. For us they are full of activity, making sure that things are progressing as they should.