Oocytes arrive in the laboratory
What is an oocyte?
An oocyte is the female reproductive cell. Oocytes develop in the ovary, inside the follicles. The functioning of the ovary in the human species is cyclical and the maturation of an oocyte occurs approximately every 28 days.
How do the oocytes arrive at the laboratory?
The oocytes arrive at the laboratory in sterile tubes immersed in follicular fluid, surrounded by cumulus cells. They are located under the microscope, cleaned and stored in the incubator with culture medium and at 37ºC.
When is it known how many oocytes have been recovered?
Within minutes of egg retrieval, all follicular fluids are analysed and the couple is informed of the number of oocytes retrieved.
Are all the oocytes obtained in a cycle of the same quality?
The quality of the oocytes is an intrinsic characteristic of each woman and obviously not all the oocytes obtained in the ovarian puncture are of the same quality.
After ovarian puncture, a heterogeneous group of oocytes is obtained, of which approximately 80% are mature, but we also find immature oocytes and oocytes with a degenerated and atresic appearance. The latter group of oocytes is not suitable for in vitro fertilisation.
Spermatozoa arrive at the laboratory
When should the semen sample be obtained?
Once the ovarian puncture has been completed, the sperm sample is requested from the male. The sample is obtained by masturbation, in a sterile container, after washing hands and genitals. For this purpose, a sterile container, gauze and gloves are provided. Once the sample has been obtained, it is handed directly to the biologists who will label it and begin to process it within an hour of obtaining it. Ideally, the patient should be sexually abstinent for 3-5 days before dropping off the sample.
Where should the semen sample be collected and can I bring it from home?
In principle, the semen sample is obtained at the clinic.
In some cases, especially in patients who have difficulty obtaining the sample, it is preferable that the sample is obtained at home before the ovarian puncture and is immediately handed over to the biologists on arrival at the clinic.
What happens if the male is unable to obtain the semen sample at that time?
In the case of a blockage in obtaining the sample, the couple goes home to try again, as the oocytes are not inseminated until 4 and a half hours after their recovery.
Can the semen sample be frozen beforehand?
There is no inconvenience in freezing semen samples prior to the IVF cycle but it is better to try to obtain a fresh semen sample on the day of the ovarian puncture as otherwise sperm motility is lost in the freezing-thawing process.
Freezing is used in cases where the male partner has previously had repeated blockages at the time of semen sampling, as well as when he cannot be present on the day of IVF due to work or personal reasons.
Is there any special preparation of the sperm necessary?
Pre-treatment of the ejaculate is essential. The sperm must be separated from the seminal plasma in order to become hyperactivated and acquire fertilising capacity.
