Planned egg freezing for fertility preservation
Planned egg freezing gives the possibility to women who cannot consider getting pregnant right now to postpone motherhood while reducing the risk of age-related infertility and miscarriage, or the need for egg donation.
In women, the egg pool is completed during fetal life. It then inexorably decreases par a spontaneous degenerative process called atresia. From approximatively one million at birth, there are only about one half left at puberty. The egg loss accelerates even further after age 35, and these older eggs have more chromosomal anomalies. This is the reason why older women have more miscarriages and are more often infertile.
Biologically, the best time for a woman to have a baby is before age 30. In our current society however, she may not be ready to consider a pregnancy at that time for social or professional reasons, and she may wish to postpone motherhood to a later time. Freezing her eggs when they are still young and healthy might help her to avoid remaining childless.
Egg freezing: how it works
At the beginning of the menstrual cycle, several eggs start to grow but eventually only one will reach ovulation. All the others degenerate. Egg recruitment and maturation is under the control of FSH and LH, pituitary hormones called gonadotropins. Adding an extra dose of gonadotropins with injections amplifies this natural signal and allows to obtain several mature eggs in the same cycle. This is the principle of ovarian stimulation, used for both fertility preservation and IVF.
Ovarian stimulation lasts only 10 to 12 days. During this time, ovarian response is evaluated with ultrasound and blood tests for hormone levels. When the criteria for egg maturity are met, the eggs are retrieved by transvaginal ultrasound-guided needle aspiration under light anesthesia. This outpatient procedure lasts 15 to 30 minutes. Harvested eggs are frozen the same day by vitrification, a freezing technique that gives the best results with eggs. Swiss law (LPMA) allows egg freezing for 5 years. This delay can be prolonged for an additional 5 years when requested in writing.
Egg freezing is best before age 35.
To have effective egg freezing, egg should be frozen when there are enough of them and when there are genetically fit. Ideally, 15 to 20 eggs should be frozen.
Frozen eggs do not guarantee a future baby.
Pregnancy rate depends on the number of frozen eggs and the woman’s age at the time of the harvest.
Even if you froze eggs, it’s best to consider starting a family as soon as possible.
Women should consider a pregnancy as soon as her personal situation makes is feasible. A live birth cannot be guaranteed with her frozen eggs. Moreover, the risk of pregnancy complications is higher in older women.
Fertility preservation is not covered by Swiss medical insurances.