Embryo donation is a medically assisted reproduction procedure that allows a couple or a single person to adopt and implant an embryo in a woman's womb in order to become pregnant. These embryos generally come from couples who have undergone in vitro fertilisation (IVF) and have supernumerary embryos that they do not plan to use.

Unlike adoption, embryo donation allows a woman to experience pregnancy. Embryo donation can be an alternative to double donation.

The embryo donation process involves several stages including the selection of an embryo, the process of thawing the embryo and transferring it into the woman's womb. If the transfer is successful the woman continues the pregnancy as if she had conceived naturally.

Embryo donation is primarily intended for couples or individuals who are unable to conceive naturally due to fertility problems. This may include couples whose gametes (eggs and/or sperm) are absent or non-viable or those who have unexplained fertility problems after several unsuccessful IVF attempts.

Embryo donation is particularly suitable in the following situations:

• couples with a mixed problem of male and female infertility,
• women who are unable to produce their own high-quality eggs,
• couples with immunological incompatibility problems,
• couples who have failed to achieve pregnancy after several IVF cycles,
• women without a partner who wish to have a child,
• female homosexual couples wishing to start a family.

Law on embryo donation varies from country to country. Generally, it has to be voluntary, free of charge and carried out as part of a procedure known as embryo reception. It can be anonymous, this means the recipient couple or woman cannot know the identity of the donor couple; or not depending on the country. 

The child born as a result of embryo donation is considered to be the child of the recipient couple. If the donation is anonymous, there will be no possible parent-child relationship between this child and the donor couple. 

Medically the protocol is fairly straightforward: the preparation of the endometrium is crucial to the success of embryo reception. Treatments are prescribed to optimise the condition of the uterine mucosa prior to embryo transfer which may vary depending on the patient's medical history. The process includes ultrasound scans and blood tests to assess the response to the treatment and to adjust it if necessary. The transfer requires the endometrium to be in ideal condition to receive the embryo which is placed in the womb via a catheter. Generally, only one embryo is transferred after surviving the thawing process.

The main concern is the lack of embryos available for adoption in many countries, where waiting times are very long and can reach several years (and even longer for certain ethnic groups for which there are virtually no embryos available for adoption). For example, according to the data available, in 2019, only 37 children were born from 151 cycles to receive an embryo in France. It is important to note that the number of attempts and births can vary from one year to the next depending on various factors: number of embryos available for donation and number of couples or women eligible and willing to receive an embryo.

This is why couples or women wishing to benefit from an embryo donation go to other countries where the majority of fertility clinics offer embryo adoption.

Embryo donation is sometimes proposed as an alternative to egg donation or double donation for the following reasons:

1. Faster: with embryo donation the embryo is already formed and ready for implantation.
2. Benefit for both partners: embryo donation may be an option compared to double donation for couples where both partners are infertile. For example, if the woman cannot produce healthy eggs and the man has low sperm quality embryo donation may be a solution.

3. Success rate: it is generally high with embryo donation because the embryos used have already reached an advanced stage of development and have demonstrated their ability to develop. The pregnancy rate following embryo donation varies between 60 and 70% in specialised IVF clinics abroad.

4. Less expensive: embryo donation is generally less expensive than egg donation. This is because there is no need to stimulate and retrieve the donor's eggs which is a costly part of the egg donation process.

It is important to note that every situation is different and what is an advantage for one person may not be for another. It is advisable to discuss these options with a healthcare professional to determine the best approach for each situation.