Embryo Freezing
In the processes of IVF (In Vitro Fertilization) or ICSI (Intracytoplasmic Sperm Injection), it is common for individuals to have embryos that are not immediately used. These surplus embryos can be cryopreserved for future treatment cycles, donated to others for their fertility treatments, provided for research, or used in educational training. Importantly, the duration of embryo storage does not impact the likelihood of pregnancy upon using a thawed embryo. However, it should be noted that not all embryos withstand the freezing and thawing process, and in rare cases, none survive.
Individuals might opt for embryo cryopreservation for several reasons, including future use in IVF or ICSI treatments, cancellation of a treatment cycle post-egg retrieval, or undergoing medical treatments that could impair fertility. Consent from all parties involved is required for embryo freezing, which outlines the specific terms and conditions related to the embryo’s use.
Utilizing Frozen Embryos:
The protocol for using cryopreserved embryos differs based on individual circumstances and the fertility clinic’s guidelines. For those with regular menstrual cycles and who are undergoing treatment, a natural cycle approach might be recommended. This involves monitoring egg development and the uterine lining’s thickness through ultrasound scans and pinpointing ovulation with urine or blood tests.
If an individual has irregular or absent menstrual cycles, the treatment may start with medication to induce a period and prepare the uterine lining for embryo implantation. At the optimal time, a specialist thaws the embryos for transfer, with up to three embryos being transferred to the uterus.
While the success rates for pregnancies using thawed embryos are comparable or slightly lower than those with fresh embryos, the survival of embryos through the freeze-thaw cycle cannot be guaranteed. Some embryos may lose cells but ideally should continue to divide before transfer. The process carries the same risks associated with fresh embryo transfers.
Embryo donation for use in another person’s fertility treatment, research, or training requires the written consent of the individuals who provided the genetic material. This consent enables the embryos to be used for the specified purposes.