trophectoderm biopsy to test the ploidy state of the ICSI embryos

As embryos are cultured in a time lapse imaging system, pictures will be taken every 20 minutes to follow the development. Each time that the embryos divides, the timing will be registered in the database. Like this, every division made by every embryo is recorded. the time the embryo needs to go from 1 cell to 2 cells, from 2 cells to 3 cells and so on.

Fertilization is calculated on all mature oocytes or on all complexes obtained after oocyte retrieval. The fertilization rate is assessed by the presence of a male and a female pronucleus 16-20 hours post fertilization. If the oocyte is fertilized, the outcome is positive, if the oocyte is not fertilized, the outcome is negative.

For all normally fertilized oocytes the further development will be assessed as the embryos are cultured in a time lapse system. This system takes pictures of the embryos every 20 minutes which shows the development of the embryo like a movie: every time that a cell divides, the hour at which it divides will be registered in the time lapse system. For each cell division, specific time frames have been described that link the embryo to develop into a blastocyst or that increases the chance of implantation. The embryo will be evaluated on day 3 and will receive an embryo score that is based on the number of cells, the appearance of the cells, fragmentation and embryo dysmorphisms. These will divide the embryo quality into 4 categories with category 1 being the highest quality and category 4 being the lowest quality. The more fragmentation and the higher the degree of dysmorphisms, the more the quality will shift to category 4.

A blastocyst is an embryo in which a cavity is visible on day 5 of the embryo development. If the cavity is present the outcome is positive, if the cavity is absent, the outcome is negative The complete process in which the development of one embryo is followed from the day of injection up until day 7 is called the preimplantation development

On day 5 of development, a score is given to every embryo. This is based on the presence or absence of a cavity, the number of cells and how tight the cells are packed. The more cells, the higher the grade, if less cells are present, the grade is lower. Based on these parameters, a final grade is calculated (3 grades) with grade 1 being the highest score.

pregnancy outcomes from the frozen embryo transfers: blood samples will be taken and the level of beta-hCG will be measured to define a pregnancy or no pregnancy. A pregnancy is defined as the best oucome. In case a pregnancy is obtained, the patient will come for an ultrasound scan between week 7-12 to checke the presence of a gestational sac and the presence of a fetal heart beat. The presence of a fetal heart beat is defined as a positive outcome, the absence is defined as a negative outcome.

The motility of the sperm will be analysed under a microscope in a Makler or Neubauer counting chamber that allows you to count the four different types of motility present in a sample.

Sperm motility is defined as the number of sperm cells that are able to progress on their own and is expressed as a percentage: the higher the percentage, the better the value is.

In order to stimulate multiple follicular development, patients will be stimulated with fixed doses of hormones. The total dosage of hormones used will be registered.

In order to stimulate multiple follicular development, patients will be stimulated with fixed doses of hormones. Once the follicular development is optimal (based on the number of follicles and the corresponding hormonal values) the patient can be triggered for final oocyte maturation. The total number of days needed during this stimulation will be registered.

During the stimulation, the hormonal profile of every patient will be measured (estrogens, luteinizing hormone, progesterone): these blood values will be compared to the number of follicles that are measured in the participants and the combination of the three blood values should correspond to the sizes and numbers of follicles measured in the participants,

Once all follicles have reached the optimal size, the participants will be triggered for final oocyte maturation. The type of trigger that is administered will be recorded.

During the stimulation, the follicles present in the participants will grow steadily and the size of the follicles will be measured to ensure a good development (in combination with the hormonal profile). These follicles will be measured by vaginal echography.