Oocyte vitrification is an assisted reproduction technique in which the ovaries are stimulated to obtain as many eggs as possible and freeze them for future use.
This technique consists of a first phase that consists of stimulating the development of oocytes in the ovaries by means of medication. During ovarian stimulation, the size of the ovary increases significantly. This can cause swelling in the abdomen and a feeling of heaviness. This growth, if exaggerated, causes the ovary to turn in on itself, thus producing what we call ovarian torsion. This is a medical emergency that usually has to be treated surgically.
For this reason, during treatment it is recommended to limit sudden movements, including sexual intercourse, especially in the final phase of stimulation, which is when the ovaries acquire greater size.
Also, an exaggerated response to the stimulation phase can provoke what we call: ovarian hyperstimulation syndrome (OHSS). The most frequent symptoms are nausea and vomiting, diarrhea, abdominal distension, and even, in the most severe cases, fluid retention in the abdomen and lung.
The second phase of treatment is ovarian puncture, which is the process by which we can remove the eggs from the ovaries. It is a small surgery that is usually performed under anesthesia. Since it is a simple and non-invasive process, the probability of complications is low. However, in 0.5% of patients there is a risk during follicular puncture of injury to the blood vessels causing hemorrhage.
Normally these hemorrhages are self-limiting and do not require medical intervention, for this reason rest is recommended in the first 24 hours after the puncture. Unfortunately, in some cases surgical intervention is necessary to coagulate the ovary.

Another very rare complication of ovarian puncture is a pelvic infection which is usually treated with the intravenous administration of antibiotics.
On the other hand, anesthesia may generate some side effects, mainly nausea, vomiting or alteration of blood pressure, but does not usually represent a risk situation.
The last phase of an egg vitrification treatment is the moment when the eggs are thawed and used. At this stage it must be remembered that it is likely that not all eggs will survive thawing. Survival rates after devitrification depend in part on the age of the patient at the time of vitrification, but generally exceed 85% survival.
