# Egg Freezing

> Citation bundle for Egg Freezing on The Treatment Registry.
> URL: https://thetreatmentregistry.com/procedures/egg-freezing
> Bundle URL: https://thetreatmentregistry.com/api/citations/procedures/egg-freezing

- Category: ivf-fertility

## Description

Oocyte cryopreservation is a form of assisted reproductive technology (ART) used to preserve human eggs (oocytes). The technique is often used to protect against future infertility or delaying childbearing: when pregnancy is desired, the eggs can be thawed, fertilized, and transferred to the uterus as embryos.

## Overview

Egg freezing, medically known as oocyte cryopreservation, is a form of assisted reproductive technology used to preserve a woman's eggs (oocytes) for future use. It is commonly used to delay childbearing and to protect against future infertility; when pregnancy is later desired, the stored eggs can be thawed, fertilised and transferred to the uterus as embryos. The first human birth from frozen eggs was reported in 1986, and although embryo freezing is a more established method of fertility preservation, egg freezing is often the preferred option for single women of reproductive age who wish to postpone having children. The egg-retrieval process is the same as in in-vitro fertilisation: the woman receives one to several weeks of hormone injections to stimulate the ovaries to mature multiple eggs, a final maturation step is given, and the mature eggs are then collected by transvaginal retrieval, usually under sedation, and frozen immediately. Because the egg is the largest cell in the body and contains a great deal of water, it must be dehydrated before freezing using cryoprotectants that replace most of the water and inhibit the formation of damaging ice crystals. Eggs are frozen either by a slow-cooling method or by vitrification, a newer flash-freezing technique that uses higher concentrations of cryoprotectant to turn the cell into a glass-like solid free of ice crystals; vitrification is associated with higher survival rates and enhanced development. Success rates vary with factors such as the woman's age, being higher in younger individuals.

## Common risks

- Ovarian hyperstimulation syndrome (OHSS) from the medications used to stimulate the ovaries
- Abdominal bloating, mild discomfort, nausea or vomiting (mild to moderate OHSS)
- Severe OHSS with marked bloating, dehydration and reduced urine output
- Increased risk of deep vein thrombosis or pulmonary embolism in severe OHSS
- Minor complications related to the egg-collection procedure

## FAQs

### What is egg freezing?

Egg freezing, or oocyte cryopreservation, is a form of assisted reproductive technology that preserves a woman's eggs. When pregnancy is later desired, the eggs can be thawed, fertilised and transferred to the uterus as embryos.

### Why do people freeze their eggs?

It is often used to delay childbearing and to protect against future infertility. It is frequently considered the preferred option for single women of reproductive age who wish to postpone having children, since it does not require sperm at the time of freezing.

### How are the eggs collected?

The retrieval process is the same as for IVF. It involves one to several weeks of hormone injections to stimulate the ovaries to mature multiple eggs, followed by transvaginal retrieval of the mature eggs, usually under sedation. The eggs are then frozen immediately.

### What is vitrification?

Vitrification is a newer flash-freezing method that is much faster than slow-cooling and uses higher concentrations of cryoprotectant, producing a glass-like cell free of ice crystals. It is associated with higher survival rates and better development compared with slow-cooling.

### Does age affect success?

Yes. The procedure's success rate varies with factors such as age, overall health and genetic factors, with higher odds of success in younger individuals.

### What is the main risk of egg freezing?

Most risks relate to the medications used to stimulate the ovaries rather than the freezing itself. The main one is ovarian hyperstimulation syndrome (OHSS), which is usually mild but can, in severe cases, cause serious complications and require hospital care.