Freezing of embryos

Since 1983 surplus fertilized eggs (embryos) have been frozen and stored for later thawing and transfer. Pregnancies following this procedure do not carry enhanced risk of abortion, chromosome abnormalities or malformations.

Danish legislation states:

Frozen fertilized eggs can only be used if both the woman and the man concede on thawing in writing.

Fertilized eggs can only be kept frozen until the day the woman turns 46 years old. After this time the eggs will be destroyed without warning. The eggs will also be destroyed in case of death of one of the partners or in case of dissolution of the partnership.

Before the freezing down of eggs can take place, you must in writing concede your agreement to freezing and storing and declare your consent to terms and conditions applying.

Fertilized eggs may only be defrosted and applied if you concede in writing

If, in your case, we have surplus fertilized eggs we can offer freezing if the eggs are suitable.

However, in just approximately 25 per cent of cases eggs can be frozen.

All surplus fertilized eggs will be cultured to the blastocyst stage. Only blastocysts with regular and stable divisions can sustain freezing. From the frozen blastocysts about 5-10 % will be damaged during freezing/warming.

The blastocysts will be defrosted on the day prior to the scheduled transfer to the uterus. The chance to become pregnant with frozen and warmed blastocysts is equal to transfer of fresh embryos.

(Document for thawing embryos, single women)

(Document for thawing embryos, couples)