Posted on 02/22/2017 in Fertility Treatment Options

How does egg freezing work?

How does egg freezing work?

Egg freezing involves the following processes: IVF ovarian stimulation which involves taking injections for roughly ten days and going through a few blood tests and ultrasound to supervise the development of the eggs; an egg retrieval procedure which is carried out to retrieve multiple eggs; and finally, egg freezing during which the retrieved eggs are frozen and stored inside liquid nitrogen tanks.

Egg retrieval procedure

To be able to retrieve the eggs for freezing, you will go through a hormone–injection process just as it is done in in–vitro fertilization. The only variation is that after your eggs have been retrieved instead of using them for immediate fertilization, they are frozen to preserve them for future use.

The egg freezing process lasts for about four to six weeks for a freezing cycle and is the same with the early stages of the IVF process.

The process involves the following:

– Two to four weeks of self–injected hormone shots and birth control pills to momentarily stop the production of natural hormones. This step is usually avoided in urgent situations like before a patient goes for cancer therapy.

– Ten to fourteen days of hormone injections to boost multiple ovulations and ripen multiple eggs.

As soon as the eggs are sufficiently matured, they are retrieved with a needle inserted into the woman’s vagina through the direction of ultrasound machine. The process is usually not painful as it is conducted under intravenous sedation. Once the eggs are retrieved, they are frozen and stored for future use. When the woman eventually wants to give birth many years later, the eggs are defrosted and injected with a sperm to fertilize it and transferred into the woman’s womb as embryos.

How long can a frozen egg last?

At most fertility centers, eggs are frozen just like embryos under the freezing temperature of –196 degrees Celsius. Scientific studies show that the frozen eggs can result to pregnancy up to 10 years after. Also, it was discovered that freezing the eggs does not reduce their quality over time.

How many eggs does a woman need to freeze to achieve a pregnancy?

Information gathered from scientific studies suggest that the frozen egg thaw rates and fertilization rates is seventy-five percent for women up to 38 years of age. This implies that if a woman freezes ten eggs, seven of the eggs are likely to survive the thaw and five to six are expected to fertilize and become embryos. Usually, three to four embryos are transferred in women up to 38 years of age. It is thus recommended that you store ten eggs for one pregnancy attempt. The majority of women of 38 years and women under 38 years can harvest ten to twenty eggs for each cycle.

The success rate of egg freezing 

The success of egg freezing can be judged through two standards: the success rate of fresh embryos and the success rate of frozen embryos. The success rate of frozen egg pregnancy rate is more than that of fresh embryos and two times that of frozen embryos.

Egg freezing after 38 years old

The pregnancy rates from frozen eggs depend on the age of the woman when she freezes the egg and is unconnected with her age when she eventually returns to make use of the frozen eggs. Thus, the possibility of women who freeze their egg after 38 years of age becoming pregnant would be lower than those of women who freeze at younger age.

This is mainly as a result of lower age cutoffs in egg freezing studies and the comparatively small number of women who have returned to make use of their frozen eggs.

There have been records of women who achieved pregnancy with the egg they freeze when they are 40years and above. In addition, pregnancies have been regularly achieved in women up to age 43 with the use of fresh embryos.

How safe is egg freezing? 

Scientific studies show that roughly five thousand successful pregnancies and babies have been born through the use of frozen eggs. The principal published study of more than nine hundred babies that resulted from frozen eggs did not show any increase in rate of birth defects when placed side by side the general population. In addition, results from a study revealed that there are no increased in rates of chromosomal defects between embryos gotten from frozen eggs and those gotten from fresh eggs.

A study conducted in 2014 revealed that egg freezing doesn’t increase pregnancy complications. Records also show that more than three hundred thousand children have been born round the globe through the use of frozen embryos gotten under slow-freeze cryopreservation procedures and these have not resulted in increased birth defects. Despite the fact that these data are encouraging, it will take numerous years of record keeping to make sure that those children born from egg freezing technology don’t have increased rates of birth defects than children born through other means.

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