Once the egg and sperm have been fertilized in the laboratory, whether conventionally or by ICSI, the embryos generated are kept in culture.
Throughout the embryonic development, the embryos are evaluated and their morphological characteristics are analyzed. When 18 hours have passed since fertilization, one can see if the zygote has two polar corpuscles and two pronuclei.
Three day old embryos have already divided and it will be necessary to evaluate the number of cells, percentage of fragmentation, if there are vacuoles, etc. In the case of 5 day old embryos, which are called blastocysts, it is also necessary to analyze the degree of expansion.
Read the full article on: How the ISCI procedure is performed – the treatment step by step ( 85).
By Gorka Barrenetxea Ziarrusta M.D., Ph.D. (gynecologist), Dr. José León Tovar M.D., M.Sc. (gynecologist), José María Sánchez Jordán M.D. (gynecologist), María de Las Heras Martínez B.Sc., M.Sc. (clinical embryologist), Marta Barranquero Gómez B.Sc., M.Sc. (embryologist), Zaira Salvador B.Sc., M.Sc. (embryologist) and Michelle Lorraine Embleton B.Sc. Ph.D. (biochemist).
Last Update: 09/06/2022
