Cryopreservation -Egg, Embryo and Egg FreezingIn the decade since reliable methods of freezing mouse embryos were first described (Whittingham et al., 1972; Wilmut, 1972a) methods have been developed for freezing the embryos of a number of other species. Frozen embryos have been used in the treatment of human infertility. Worldwide, in all reputable IVF Centre's, cycle eggs are frozen in the same way. In our centre, pregnancy rates via our egg freezing-thawing program are almost identical to using fresh eggs.
Egg freezing, also known as mature oocyte cryopreservation, is a method used to preserve reproductive potential in women. Eggs are harvested from your ovaries, frozen unfertilized and stored for later use. A frozen egg can be thawed, combined with sperm in a lab and implanted in your uterus (in vitro fertilization)Today, thanks to egg freezing (egg cryopreservation) programs, eggs collected after a short period of stimulation of the ovary can be stored for a long number of years and when a woman thinks of getting pregnant these can be thawed and used. No matter what age the woman will be by the time she decides to get pregnant, her eggs will be frozen in the condition when they were retrieved. Eggs are a complex and huge structure and they are delicate to low temperatures. During the first researches in the area, pre-mature eggs (oocyte) were suggested to be frozen, however, today, research shows that mature eggs are more durable in the process of freezing. After collection, eggs are cleansed of the surrounding cells and normal/healthy mature eggs are frozen. Frozen embryo After embryo transfer to the patient, with the consent of the couple, the excess embryo (which generally is in good condition) can be frozen and stored via vitrification . In this way, we are able to transfer embryos without stimulating the ovaries. We get very successful results via vitrification. When compared to slow and traditional freezing methods, embryos are less damage in this technique and pregnancy rates have similar results to cases where non-frozen embryos are used. When freezing, the timing of reducing the temperature and using the appropriate preservative agent is vital. After the eggs are frozen, they are placed into liquid nitrogen (-196°C). Eggs stored in liquid nitrogen can be kept safe without genetic deformation for a long time. In babies, born of frozen-thawed eggs, no defects related to this process have been encountered so far. In initial trials about 60% of the eggs could survive after they were thawed, however, this rate has reached 80%-90% now. In addition, lower percentages of pregnancy, after thawing the eggs, at the beginning, have been highly increased due to the use of microinjection.
Due to career planning and socially acceptable living conditions, there are many cases of A/ women planning marriage and childbirth towards older ages. B/ single parent families, in the lowest 20 percent of families with children aged four to five years old, single parent families made up 48.9 percent of statistics. The fact remains, both in natural ways and in IVF treatment, a woman’s age is very critical criteria.
What Happens After an Embryo
Embryo transfer is the final step in the IVF process.
Embryo transfer is a crucial moment in your IVF treatment.
Once embryos are transferred into the uterus, it typically takes 10 days until hCG levels are high enough to detect on a pregnancy test. However, many of our patients prefer to know what should be happening at each day so they can imagine the progress and look forward to that final day when they can see if the treatment has been successful. In some cases, patients experience a false negative on day 10 and it is always worth taking additional pregnancy test 2-4 days afterwards.
Can you improve implantation chances after an IVF transfer? It's the question all our patients ask, and rightly so. Your embryo transfer went well. Your emotions are highly charged. You'll do anything to make it happen.
Who might benefit from embryo freezing/egg cryopreservationIn short, whatever the reason is (medical or personal etc.), today, thanks to this highly successful program, women have the chance to freeze their eggs.Freezing SpermThis is a program which has been highly effective since the beginning of IVF. There is no difference in the percentages of pregnancies which involve frozen-thawed sperm and those that involve the use of fresh sperm in our clinic. Sperm freezing is suitable …
- Patients who have excess good quality embryo after embryo transfer,
- Patients who have a high risk of hyperstimulation (when the ovary responds more than necessary and thus transfer is postponed to a later date) during an IVF procedure,
- Patients who for some reason (chemotherapy or radiotherapy against cancer, or any other urgent medical procedure) need to postpone transfer to a later date can make use of frozen embryos. In such cases, after thawing the frozen embryos, transfer can be possible, following the completion of their treatment.
- Those who will receive cancer treatment such as chemotherapy or radiotherapy; who will have to have their ovary removed but will be able to keep their uterus can benefit from egg freezing before these procedures have the opportunity of becoming pregnancy
- Women who plan to have children at later ages (due to career plans, not thinking of getting married at an early age etc
- Patients with a risk of developing hyper stimulation during IVF treatment [in this method the eggs are frozen, a few months later it is possible to be transferred through microinjection].
- Couples, when for some important reason (emergency health or work related issue) the male partner cannot be present to provide the sperm during egg collection.
- Before surgical operation/chemotherapy/radiotherapy regarding male reproductive organ related tumors,
- Prior to radiotherapy/chemotherapy due to any sort of tumor existence which might affect the production of sperms
- When there is a critical deformation in the sperms or as a precaution in cases where there is a risk of having no sperm at all in the future
- When for some important reason (emergency health or work related issue) the male partner cannot be present to provide the sperm during egg collection.
- Day 1: The blastocyst begins to hatch out of the shell – this is called hatching. The cells will carry on dividing throughout this process.
- Day 2: The blastocyst continues hatching and begins to attach itself to the uterine lining – this is an incredibly important part of the process.
- Day 3: The blastocyst attaches deeper into the uterine lining and implantation begins. It’s perfectly normal to experience some bleeding or spotting around this time and it’s not a cause for concern.
- Day 4: The blastocyst digs deeper into the uterus and attaches to the endometrial blood supply. Some people experience more bleeding at this stage, but a lack of bleeding or spotting also doesn’t mean that it has not been successful.
- Day 5: Implantation is considered complete and the embryo is developing, along with the cells that will eventually become the placenta.
- Day 6: Placenta cells secrete hCG (human chorionic gonadotropin), which is the hormone picked up in pregnancy tests. The hormone triggers increased progesterone release in the first trimester to enrich the uterus lining and sustain the growing embryo/foetus.
- Day 7: The embryo is now a foetus and yet more hCG is present in the blood stream as the placenta continues to develop.