'How many embryos do we have?' may be the most-asked question in any IVF journey. This guide explains what happens in the laboratory, why numbers drop at every step — and why that is normal.
Not every follicle contains a mature egg, not every mature egg fertilises, and not every fertilised embryo keeps developing. That decrease per step is not a sign that something is wrong — it is the natural selection that happens invisibly in the body, now visible in the lab. Ten eggs leading to three or four good embryos is a common picture.
An embryo is assessed on the pace and regularity of cell division and on fragmentation (loose cell debris). An embryo that reaches the blastocyst stage on day five has already proven its developmental strength. In the EmbryoScope this assessment is based on thousands of time-lapse images, without ever taking the embryos out of their protected environment.
As a woman gets older, the share of embryos with an abnormal number of chromosomes increases — the main explanation why the chance per attempt declines with age and miscarriages become more frequent. In cases of recurrent miscarriage, multiple failed attempts or higher age, screening (PGT-A) can be worthwhile: transferring a chromosomally normal embryo increases the chance that the pregnancy continues.
Grading predicts chances, not outcomes. Healthy children are born from 'average' embryos, and even a perfect embryo sometimes fails to implant. Never let a single grade discourage you — the medical team always looks at the whole picture.
Good embryos that are not transferred can be frozen and used in a later attempt through a cryotransfer — without a new stimulation. They remain yours together and are only used with your consent.
This guide is general information, not personal medical advice. Submit your file free of obligation — the medical team reviews it and you hear from us within 7 working days.