Prof Homburg, Amit Shah and Anil Gudi
An ideal cycle of in-vitro fertilisation (IVF) should produce a number of embryos that could potentially be placed in the uterus in order to produce a pregnancy. In order to avert the very high rates of multiple pregnancies with all their associated complications, the trend today is to go for the placement in the uterus of just one embryo. This we do in those with the best chance to conceive, i.e. younger patients on their first cycle. Obviously, we should choose the embryo with the best chance of producing a baby, but how can this choice be made. Up to now we have mainly relied on the good judgement of the embryologist who, by taking the embryos out of the incubator and inspecting them on day one, day three and sometimes, day five following the egg collection and insemination, will judge which one is to be placed in the uterus. This is done purely on the appearance of the embryo and a grading system is often used. Although this has generally been a reliable method, it is far from fool proof and surprises occur in both directions; beautiful looking embryos that fail to implant and unkempt embryos that implant beautifully. A prolonged attempt was made to adjudge the best embryo by examining the fluid (medium) in which it was cultured for a number of different products but this did not produce reliable answers.
When it became apparent that the speed of growth and cell division (cleavage) of the embryo cultured in the incubator was a very good indicator of its quality, a time-lapse photography system was devised which would record a photograph every 5-15 minutes. This enables a visual record of the development of the embryo which could be inspected at any time by the embryologist without the removal of the embryo from the incubator, a potentially damaging procedure. The choice of the best embryo seems to have been made much easier and more accurately with this time lapse photography technique. Personally speaking, this seems to me a game-changing innovation.