Embryos and gametes cryopreservation
The first case of baby born by frozen embryo (blastocyst) transfer was reported in 1985. To enhance the success rate of infertility treatment, cryopreservation or freezing technique of embryo or gamete is a mandatory step to help couple take a baby back home.
What is cryopreservation?
Cryopreservation is a process of freezing embryos or gamete and storing them in liquid nitrogen (-196oC), which no cell activity take place at that stage. By freezing embryos, the ART cost can be reduced in the future cycle. The cryopreservation can also be used to store sperm or oocytes in case that the male partners are not available on the day of egg collection, or couple cannot undergo the fertilization on the day of egg pick up, or in case the women want to keep her own eggs for the future use. There are two cryopreservation techniques that have been used in IVF Lab
- Vitrification – new, easy and high success rate
- Slow freezing – old fashion of cryopreservation in human ART
SFC’s cryopreservation laboratory has been using the vitrification technique to freeze embryos or gametes, and we are one of the first clinics in Bangkok that establish Egg Freezing program.
Cryopreservation of embryos
At SFC, embryos can be frozen at any stage, from zygote stage to blastocyst stage. Good quality, surplus embryo will be frozen after transfer for future use, or in case that fresh transfer cannot be done because of high risk of severe ovarian stimulation syndrome, unsuitable uterine or hormone conditions. Embryos are also frozen after blastocyst biopsy for PGS using comprehensive chromosome screening (CCS).
Why would I want to freeze embryo?
Embryo cryopreservation is recommended in the following cases:
- If you want to check all 23 pairs of chromosomes (CCS) before transfer
- If your hormone level and womb condition are not suitable for fresh transfer
- If you have extra embryo left after fresh transfer
Benefit for embryo cryopreservation
- Keeping the leftover top-quality embryos for future transfer to avoid unnecessary ovarian stimulation
- Waiting the result of CCS (aCGH/NGS) after blastocyst biopsy
- Increasing the accumulative pregnancy rate
- Decreasing the chance of ectopic pregnancy
Safe Fertility Center recommends frozen blastocyst transfer, after comprehensive chromosome screening (CCS) to maximize take home baby rate. Our scientists have highly experienced in embryo cryopreservation, with more than 5,800 frozen embryo transfer cycles in a past few years.
Cryopreservation of oocytes
Oocyte cryopreservation is a freezing process that provide for helping women to store her egg at younger age or due to medical conditions. The process of egg cryopreservation involves ovarian stimulation, egg retrieval and egg freezing for later use. A quality of eggs depends on female’s age at the date of egg retrieval.
Proposed application of oocyte cryopreservation
- Medical conditions
- Women who receiving gonadotoxic therapies for cancer or other medical diseases.
- Genetic disorder, such as BRCA mutation that have risk of breast cancer or other genetic disorder associated with Premature ovarian failure (Turner syndrome, permutation of fragile X)
- Unable to collect sperm on the day of oocyte pick up
- Defer childbearing – to store egg to use in later date.
Safe fertility center has highly skilled staffs to provide egg-freezing program and has a higher in egg survival rate after egg thawing. The ART outcomes between thawed and fresh egg at SFC are similar, which is including fertilization rate, implantation rate and clinical pregnancy rate.
Cryopreservation of sperm
Cryopreservation of sperm is a freezing sperm process and store in liquid nitrogen to preserve and use for IUI or IVF/ICSI. Sperm can be stored many years with a reasonable quality after thawing. Sperm freezing has advantages both to the couple and to the staff in term of egg and sperm collection may be done on separate occasions.
Source of sperm for freezing
- Ejaculated sperm
- Surgical retrieval sperm – epididymal or testicular aspiration or biopsy
- Donor sperm
Why would I want to freeze sperm?
There are many situations that may occur during or before infertility treatment. Such as men who…
- Work in high risk occupations
- Away from home while female partner on an infertility treatment
- Have cancer therapy that use gonadotoxic agents (radiation or chemotherapy)
- Surgical sperm retrieval
Before freezing process, Male partner have to arrange blood tests for routine sexual transmitted disease. Sperm analysis will be arranged to check the sperm count, motility, morphology, pH and volume. The stored sperm may be used with IUI or IVF/ICSI depend on the treatment option. Safe Fertility Center has many oversea couples which male partner cannot come to clinic to collect sperm or undergo the surgical sperm retrieval on the day of egg pick up. So, sperm freezing is a service that can resolve this situation.