The story begins with Carlos, a 41-year-old Spaniard from Alicante who works for an IT company in Switzerland, deciding to become a single father. After considering the possibility during the Covid-19 pandemic and discussing it with both his family and his employer, he began a surrogacy process in Mexico. 

The procedure was performed there using her genetic material and an egg from a donor. The woman who carried the pregnancy, therefore, did not contribute any genetic material to the embryo. The child was born in Mexico on April 24, 2024. 

Months in Mexico awaiting a resolution 

After the birth, a complex administrative and legal process began. Carlos remained in Mexico with his son while awaiting a ruling that would determine he was the child’s sole parent. This is the established procedure in Mexico for surrogacy arrangements initiated by a single individual. 

The ruling came three months after the birth, in July. It was necessary to wait another ten business days for it to become final. However, with only two days remaining in that period, a judicial strike began that lasted for approximately three months. 

As a result, father and son had to remain in Mexico much longer than initially planned. Carlos continued working remotely for his Swiss company, adapting to the time difference, while the boy was left without a passport and unable to leave the country. 

The father describes that period as a situation of enormous uncertainty: his son lacked documentation that would allow him to travel, he did not have medical insurance, and both of them were far from their family. 

Faced with these difficulties, Carlos went to the Spanish consulate, but, according to his testimony, he found no solution there. He even recounts that a consulate official told him there were instructions to halt these types of processes, in line with the Spanish government’s stance on surrogacy, a practice that is illegal in Spain. 

Finally, on January 10, 2025, more than eight months after his birth, the child obtained a provisional passport valid for one year, which allowed him to leave Mexico with his father. 

The problem of parentage upon arrival in Spain 

Leaving Mexico, however, did not end the legal difficulties. Carlos’s lawyer, Ana Miramontes, explains that when a child born through surrogacy is to be registered in Spain  and the person initiating the process is a single father, many Spanish civil registries apply the principle that the mother is the woman who gave birth, regardless of whether or not there is a genetic relationship between them.  

That is precisely what happened in this case. Upon registration in Spain, the child was listed with Carlos’s first surname and the surname of the Mexican woman who had carried him. In this way, the surrogate mother became legally linked to the child, even though the surrogacy arrangement had been designed so that Carlos would be the sole parent and she had no biological connection to the child. 

To address the consequences of this situation, Carlos filed a lawsuit requesting that the surrogate mother be stripped of her parental rights. His goal was to be able to exercise, without interference, the decisions that correspond to the person who holds that responsibility over a minor. The formal existence of two parents could affect, for example, decisions related to the child’s education, certain medical treatments, or other important aspects of their life. 

According to Miramontes, the deprivation of parental rights of the surrogate mother is one of the ways used in these types of situations to adapt to Spanish legislation a family reality originating through surrogacy in another country. 

A sentence with unexpected consequences 

The resolution of the procedure came in April 2026. The judge did not accept to definitively remove the parental authority from the woman, since he considers that to adopt a measure of this nature it is necessary that there is a serious and repeated breach of the duties of the parent and that, in addition, the decision is beneficial for the minor. 

Instead of stripping her of parental rights, the court decided to temporarily suspend their exercise and grant them exclusively to Carlos. The father also received custody, which allows him to make decisions regarding the child himself. 

The ruling also did not establish a visitation schedule between the surrogate mother and the child. However, the legal recognition of the woman as the mother had an unexpected consequence for the father: if she is legally the child’s parent, she must also assume certain financial obligations toward the child. 

The court ruled that the woman must pay child support of 150 euros per month. This amount was determined considering that her income had not been proven to exceed the minimum wage. The support payment is intended to cover the child’s basic living expenses, including food, housing, education, and clothing. 

But their obligations don’t end there. The ruling also stipulates that they must cover 50% of any extraordinary expenses the child may incur that are not covered by Social Security. These include expenses related to prolonged illnesses, surgeries, orthopedics, vision care, orthodontics, psychological support, speech therapy, and rehabilitation. 

Carlos believes the measure makes no sense given the circumstances in which his son was born and has stated that he has no intention of demanding payment of this pension from the woman. 

The issue of surnames remains open 

The father also failed to get the courts to accept another of his requests: that the child be registered in Spain with both his surnames. The child’s legal status thus presents a new peculiarity. Carlos works in Switzerland, and the child currently has a Swiss passport. This document does include both of his father’s surnames, just as he had intended from the beginning. However, the Spanish documentation still lists the surname of the woman who carried him as the child’s second surname. Carlos questions the possibility that his son could end up with documents from different countries bearing different surnames and intends to continue demanding that Spain also recognize both of his surnames. 

The case is further complicated by a subsequent circumstance. After the first experience, Carlos again resorted to surrogacy in Mexico to have a second child. For this second process, an egg from the same donor as in the first was used, although the pregnancy was carried by a different woman. According to the father, the two brothers thus share the same genetic origin, but were carried by different women. This time, M. was able to leave Mexico with a Mexican passport that included both of Carlos’s surnames. 

The father anticipates, however, that when he has to resolve the registration status of his second child in Spain, he will encounter the same problem. If the criterion of attributing maternity to the woman who gave birth is applied again, each sibling could end up having a different second surname in Spain, corresponding in each case to the woman who carried them. 

The court proceedings in Alicante thus highlight one of the situations that can arise when a surrogacy process carried out in another country must later be integrated into the Spanish legal system. In this case, the woman who carried the child, without contributing genetic material and within the context of a process aimed at establishing paternity, has ended up being legally recognized as the mother in Spain. 

Bioethical assessment 

This case highlights some of the profound ethical and legal contradictions surrounding surrogacy . The obligation imposed on the surrogate mother to pay alimony may seem paradoxical, but it reveals a prior problem: the attempt to separate, through an agreement, gestation, motherhood, and parentage.   

From a bioethical perspective, gestation cannot be considered a mere biological service. Although the woman does not contribute genetic material, a mother-child relationship is established during pregnancy that cannot be reduced to the function of gestating for others. Surrogacy deliberately introduces a rupture of this bond by stipulating, from the outset, the transfer of the child after birth. 

The case also illustrates a clear fragmentation of motherhood: one woman provides the egg, another carries the child, and a third person assumes parental responsibilities. This separation raises questions about the child’s identity and origins, and the child’s best interests must prevail over the wishes of the adults. 

The desire to be a parent, however legitimate and understandable, does not create a right to the child nor justify any procedure to achieve it. A child possesses inherent dignity and cannot become the object of a reproductive agreement, just as a woman should not be reduced to her capacity to bear children. 

Once born, the child must receive all necessary legal protection, regardless of the circumstances of their conception. However, protecting the child does not imply considering the practice that led to their birth ethically acceptable. 

The difficulties that arose in this case—parentage, parental rights, surnames, and financial obligations—show that the issue of surrogacy is not solely legal. There is a prior anthropological and bioethical question: the dignity of the woman and the child cannot be subordinated to contracts, desires, or reproductive plans of third parties. 

Designing a process like the one in question, which deliberately excludes the mother from the family unit, seems to prioritize the father’s reproductive desires over the child’s best interests. Furthermore, doing so in violation of the laws of the country where the child is to be registered, and repeatedly, does not benefit the child either, as can be seen from the difficulties that accumulate in the process, both now and in the future. 

As is the case in many surrogacy arrangements, the child may in the future demand access to the identity of the biological parents,  gamete donors , and surrogate mothers. 

In this case, in addition to the commissioning father, knowing the identity of the genetic mother (donor of the two oocytes used) plus that of the two gestational mothers can be problematic for the child who requests it. 

Finally, we must add the bioethical difficulty associated with the instrumentalization of the pregnant woman, who, often in situations of great precarity, accesses the surrogacy processes in exchange for financial remuneration, assuming risks to her health during pregnancy and childbirth, and having to face other difficulties, such as those related to the gestation of a child with a disability, in which she may be coerced to abort as established by many contracts, or those in which the commissioning parents abandon their desire for parenthood, aggravating the situation of vulnerability for both the pregnant mother and the gestated child.   

Fatherhood and motherhood, the fruit of the complementary gift of man and woman, occur naturally within the environment of a family, a bosom in which the transmission of life, its reception, upbringing, and educational accompaniment respond to the deep needs of every human being. 

When the child’s well-being ceases to be the priority, because the parents’ desires for parenthood take precedence, the weakest one will suffer the most from the consequences. 

Julio Tudela. Cristina Castillo. Bioethics Observatory. Catholic University of Valencia