The parentage of embryos created through assisted reproduction techniques is a complex and little-known legal aspect that directly affects the rights of the parents, especially in cases of separation, change of partner, or subsequent treatments.
According to Law 14/2006 on human assisted reproduction techniques, when a couple consents to the creation of common embryos, both are legally and permanently linked as parents of any future offspring derived from their use.
However, this consent can be revoked at any time. Regardless of the informed consent signed, if there are common embryos, both parents are irrevocably committed as parents of any offspring from those embryos, even if the relationship ends years later, since both hold rights and obligations regarding those embryos.
“At the moment a couple decides to create embryos together, those embryos legally belong to both, and both must decide their fate,” explain the legal department of IVF-Life. “In our clinics we rigorously apply the protocols established by law to protect everyone involved in the process,” they add.
One key point is that, in the case of married heterosexual couples (though not in de facto partnerships), the parentage of the embryo is automatic for both spouses. Thus, if the couple separates and the woman wishes to use the embryos individually to attempt pregnancy, the man will still be legally recognized as the father of the future baby, regardless of whether she signs as a single mother.

In this regard, when two people come to the clinic as a de facto or married couple, their clinical histories are automatically linked, so if in the future one member arrives alone or with a different partner, they must prove they are legally separated or divorced from the previous partner, as they cannot claim to be married to two people or have two de facto partners simultaneously.
“It is not enough for the patient to now want to sign as a single woman and have a child alone or with a new partner; she must present a reliable document confirming the absence of a legal link with her former spouse. In this way, clinical histories can be unlinked. This can be a notarized declaration or similar, all to prevent automatic parentage with whoever is legally her husband at the time of treatment,” insist the legal department.
Besides informed consent (IC), IVF-Life clinics require the couple to declare their marital status through a responsible declaration—that is, they must indicate if they are spouses or de facto partners to be eligible for joint treatment. This declaration has significant legal implications, since parentage largely depends on marital status according to current regulations.
In case of separation, vitrified (frozen) embryos cannot be used without the express signature of both parents.
If the couple decides to separate, they must agree on the fate of the frozen embryos. The options are:
If there is no agreement and after two attempts to renew the informed consent by the clinic without response, the law allows embryos to be considered abandoned, and the clinic will decide their fate according to regulations.
In the case of homosexual couples, the law does not establish automatic dual maternal parentage, even if married. Only the gestational mother is legally recognized at birth. The non-gestational mother must express her agreement in the Civil Registry to be recognized as the child's legal parent.
Mothers using the ROPA method at IVF-Life
To avoid legal conflicts and protect both gestational persons and legal parents, IVF-Life clinics apply exhaustive protocols. “The law is well drafted, but we must be very cautious. Our role is to ensure patients are well informed and act within the legal framework.”
In this regard, legal consequences for forgery or lying about marital status fall directly on patients, not on the medical center. Signatures, documents, and responsible declarations regarding marital status or other aspects are the responsibility of the patient's truthfulness, and the medical center's duty is to act with maximum diligence during the process.
Creating embryos together is not only a medical decision but a lasting legal commitment, as informed consents are after all binding contracts with respective rights and obligations. The implications of parentage in assisted reproduction treatments go far beyond the treatment moment and may affect future decisions related to motherhood, fatherhood, custody, and child support.