Embryo culture and Embryo tranfer
A cultured egg is usually inspected under the microscope at 18 hours after placing it with sperm, and then again about 30 hours later.
The inspection at 18 hours is important, because this is a milestone time when usually the first signs of normal fertilisation can be observed. Normally the embryo will have divided into two or four cells in 48 hours, although occasionally growth may be somewhat more advanced. Before an embryo is transferred back to uterus, we make sure it appears normal. If there is doubt about this we may wait a further 24 hours before taking a decision whether we should transfer it or not (With current scientific evidence the success rates are similar if embryo transfer takes place on day 2 or 3 after fertilization).
Embryos that seem seriously abnormal are not transferred and their development is monitored.
When an embryo is ready to be put into the womb, it is loaded into a fine catheter together with a small drop of culture medium.
The culture fluid containing the embryo or embryos is placed with gentleness into the womb. This is normally very easy and painless and needs no anaesthetic. At this stage, once an embryo has been transferred, all women are naturally nervous about what they can or cannot do. Some are so nervous that they lie rigid in bed for hours at a time. This is unnecessary – we simply want you to lie down for twenty minutes to help you relax.
Remember that embryos never immediately implant after transfer – this takes place several days later and this is not influenced by routine activities – if implantation was prevented by moving around, no woman would ever get pregnant.
We do not feel that you should regard yourself as an invalid, but it isn’t unreasonable to take it easy for a few days. We have no evidence that even these simple precautions make any difference to success or failure, they are recommended simply for emotional reasons. There is definitely no need to stay in bed.