New family models thanks to assisted reproduction

Expanding the Definition of Family

Social change and scientific innovation have also reshaped the traditional concept of the family. Changes in mindset, new legislation, and reproductive technology have opened the door to new family structures that were previously unrecognized.

Today, families may be formed by married lesbian couples or by single women who choose motherhood on their own. These growing groups share one thing in common: the decision to become mothers without a male partner, made possible by treatments like IVF or artificial insemination with donor sperm.

Legal Recognition in Spain

The legal landscape changed with Law 13/2005, which amended the Spanish Civil Code to allow same-sex marriage. The revised Article 44 states: “Men and women have the right to marry in accordance with this Code. Marriage shall have the same requirements and effects whether the spouses are of the same or different sex.”

As a result, female same-sex couples can now marry and use assisted reproduction to have children. If they are legally married at the time of treatment, both women can be listed as mothers on the child’s birth certificate. If they are not married, only the biological mother will be legally recognized unless the partner initiates a formal adoption process.

Male same-sex couples, however, must turn to surrogacy—a practice not permitted in Spain—if they wish to have biological children. Adoption remains the only legal path within the country.

Single Mothers by Choice

Another significant change involves the rise of single women choosing motherhood. More and more women, typically between the ages of 35 and 39, with higher education and economic stability, are deciding to become mothers independently using donor sperm. For many, this decision follows the achievement of other life goals, especially in their professional careers.

Some also opt to freeze their eggs during their most fertile years, postponing motherhood for when the time feels right—alone or with a future partner.

Our Experience at URE Centro Gutenberg

At URE Centro Gutenberg, approximately 7% to 10% of fertility consultations now come from single women and female couples.

In the past decade, more than 700 patients—including heterosexual, lesbian couples, and single women—have used our sperm bank. Of those:

• 62% were lesbian couples or single women.
• 38% were heterosexual couples (mostly due to medical conditions).

A decade ago, the use of donor sperm was mostly limited to heterosexual couples (about 77%). Today, this has reversed—most donor sperm users now belong to new family models.

Clearly, something is changing—and assisted reproduction is at the heart of this transformation.