Twiblings and Surrogate Twins: Understanding the Differences and Similarities

All About Surrogacy 

Surrogate “twiblings” are a growing phenomenon in the surrogacy world, and they are becoming an increasingly popular option for intended parents who want to have more than one child. Here, we’ll explore the concept of twiblings, the process of twiblings surrogacy, and why some intended parents choose to have twiblings rather than traditional twins.

What Are Twiblings?

Twiblings, coined by combining the words “twin” and “siblings,” refers to two biologically related children born simultaneously. Unlike twins who share a womb, twiblings are conceived through IVF using the eggs and sperm of the same people. The fertilized eggs are then implanted in two surrogates who carry the pregnancies to term. The resulting children are biological siblings but not twins.

This unique approach to family building offers a viable alternative to traditional twin pregnancies. It is gaining popularity among intended parents who want twins while reducing the risk of complications that often come with carrying multiple babies.

Why Some Parents Want Twins

Many parents dream of having twins. The idea of having two babies at once is appealing for several reasons. While not all-encompassing, here are a few reasons:

  • Completeness: For some parents, having two children at once immediately feels like a complete family.
  • Convenience: Parents of twins can go through many of the stages of childhood only once, such as potty training, teething, and having threenagers.
  • Bonding: Twins have a special bond that starts in the womb and can continue throughout their lives.

Why Having Surrogate Twins Can Be Risky

Why Having Surrogate Twins is Risky

While having twins may be appealing, twin surrogacy comes with added risks. Twin pregnancies are associated with higher rates of complications, including premature birth, low birth weight, and gestational diabetes. Twins are also at higher risk for developmental delays, cerebral palsy, and other health issues.

Twins can also be physically and emotionally demanding for the surrogate. Twin pregnancies often result in more discomfort, fatigue, and physical strain than a singular pregnancy. The surrogate may also experience psychological stress and anxiety, worrying about the health and well-being of both babies throughout the pregnancy.

Twiblings: A Better Option

Twiblings offer a safer alternative to traditional twin pregnancies, allowing intended parents to have two children at once. With twiblings, the eggs and sperm of the same people are used to create two embryos, which are then implanted in two different surrogates. This reduces the risk of complications from carrying multiple fetuses in the same womb.

In addition, twiblings offer parents the opportunity to have two biologically related children born at the same time. While not traditional twins, twiblings share a unique bond and connection that comes from being conceived at the same time, in the same way, and from the same biological parents.

Differences Between Twins and Twiblings

The main difference between twins and twiblings is how they are conceived and carried. Twins are two babies that develop from a single fertilized egg that splits into two embryos, while twiblings are two babies conceived through in vitro fertilization (IVF) using the eggs and sperm of the same people but carried by two different surrogates.

  • Genetic makeup: Twins share identical or fraternal genetic makeup, depending on whether they are identical or fraternal twins. At the same time, twiblings are full siblings sharing genetic material from their biological parents. Other differences between twins and twiblings include:
  • Gestation: Twins share the same gestational period and are born at the same time, while twiblings may be born days or weeks apart, depending on the timing of their surrogate pregnancies.
  • Developmental milestones: Twins often reach developmental milestones at the same time, while twiblings may develop at slightly different rates due to differences in their prenatal environments.

What’s similar in twins and twiblings?

The main thing that twins and twiblings have in common is that they are siblings born close in time to each other. Although twins and twiblings differ in conception and gestation, they share a biological connection and often develop a close bond due to their shared experiences. Other notable similarities include:  

  • Similar physical appearance: Twins, in particular, often closely resemble each other due to their genetic makeup. Twiblings may also look similar if they share physical traits with their biological parents.
  • Shared interests and experiences: Twins and twiblings may share interests and experiences due to growing up together and being close in age.
  • Family dynamic: Twins and twiblings can have an extraordinary impact on their family dynamic, as having two children close in age can be challenging and rewarding for parents and siblings.

Risks and Rewards of Twibling Surrogacy

Twiblings surrogacy can be a fulfilling option for parents who want twins without the added risks associated with traditional twin pregnancies. However, like any form of assisted reproduction, it is crucial for parents to carefully consider the potential risks and rewards before pursuing this option.


  • A twibling surrogacy journey begins with the same steps as traditional IVF, including egg retrieval, fertilization, and embryo transfer. The only difference is that the resulting embryos are implanted in two surrogates rather than a single surrogate. It can be a good option for couples who want twins but are concerned about the risks of carrying multiple fetuses, such as premature delivery, low birth weight, and developmental delays.
  • It can also be a good option for same-sex male couples who want to have biological children that are genetically related to both partners.


  • One potential downside of having twiblings is that it can be more expensive than traditional IVF or single surrogate surrogacy, as it involves using two surrogates and completing two separate embryo transfer cycles.
  • Another potential issue is that it can be more logistically challenging, as parents may need to coordinate the care and schedules of two surrogates and potentially two newborns.
  • The legal and ethical considerations of having twiblings can be complex, particularly in cases where the surrogates are carrying embryos from two different biological parents. It is essential for parents considering twibling journey to work with a reputable surrogacy agency and consult with legal professionals to ensure that their rights and the rights of the surrogates are protected.

Final Thoughts

In conclusion, twiblings surrogacy offers a unique and increasingly popular alternative for parents who want twins without the added risks associated with traditional twin pregnancies. By utilizing two different surrogates to carry embryos from the same biological parents, twiblings are born at the same time but are biologically siblings rather than twins. While the twibling journey can offer several advantages, such as the reduced risk of complications and increased genetic diversity for same-sex couples, it is essential to consider this option’s potential challenges and costs. 

Overall, twiblings surrogacy can be a viable and fulfilling option for intended parents seeking to start or expand their family. As with any form of assisted reproduction, parents must work with reputable agencies and legal professionals to ensure that their rights and the rights of their surrogates are protected.