When a woman undergoes in vitro fertilization (IVF) using donor eggs, there is often a higher possibility that she becomes pregnant with twins. Compared with natural conception or IVF pregnancy using the woman’s own eggs, the chances of twins with donor eggs are higher. But what are the reasons? Is it just a coincidence? In this article, we are going to answer this question and also learn if the egg donor’s genetics affect having twins or not.
Chances of Twins with Donor Eggs VS. Own Eggs
Egg donation in Iran is a very common fertility treatment that has helped thousands of couples from all over the world. When a couple wants to use donor eggs for conceiving, they need to go through the IVF process. In this condition, the donor eggs conceive by the sperm of the intended father (or a donor) and then the formed embryo is transferred to the intended mother’s uterus to hopefully hatch and grow into a pregnancy.
What are the Chances of Twins with Donor Eggs?
The chances of twins with donor eggs go higher when it is compared to using one’s own eggs or conceiving naturally without IVF. This increased chance of having twins with donor eggs is due to the following facts:
- In IVF, it is common to transfer more than one embryo into the uterus to increase the likelihood of a successful pregnancy. When multiple embryos are transferred, there is a higher chance that more than one will implant and develop, which results in multiple pregnancies.
- Donor eggs are typically harvested from young, healthy donors who have a higher likelihood of producing multiple eggs during a single IVF cycle. This means that there may be more embryos available for transfer, which most probably have a high quality, and as a result, the chance of a twin pregnancy will be increased.
It is important to note that while the chances of twins with donor eggs might be higher, it is not a guarantee. Conceiving twins’ pregnancy ultimately depends on a variety of factors, including the number and quality of embryos transferred, the recipient’s age and health, the age of the donor, and the type of fertility treatment.
Generally, the chances of twins with donor eggs are higher than with natural conception because fertility treatments such as in vitro fertilization (IVF), intrauterine insemination (IUI), and Intracytoplasmic sperm injection (ICSI) often involve transferring multiple embryos into the uterus to increase the chances of pregnancy. (Does ICSI increase the chance of twins? Read more).
Which Method Does Have a higher chance of Twins?
Couples who use assisted reproductive technologies such as IVF and ICSI have about a 30 to 35 percent chance of having twins and a 5 to 10 percent chance of having triplets or more; therefore, these methods do not have a huge difference in the odds of turning to multiple pregnancies. While transferring multiple embryos may increase the likelihood of a successful pregnancy, it also increases the chance of having twins.
In the below table, you can see the comparison of the chances of having twins through natural pregnancies, IVF/ICSI pregnancies, and IVF/ICSI+ Donor egg pregnancies.
| Chances of Having Twins | ||
| Natural pregnancies | IVF/ICSI Pregnancies | IVF/ICSI+ Donor egg pregnancies |
| About %12.5 | About %30-35 | About %40-45 |
According to the Centers for Disease Control and Prevention (CDC), the rate of twin births in the United States has increased in recent years and is now about 32.6 twin births per 1,000 live births.
Conceiving twins can have both advantages and challenges. Some of the potential benefits of having twins include:
- Double the joy: Having twins means that you get to experience the joy of two babies at once, which can be incredibly rewarding.
- Built-in playmates: Twins often form a close bond with each other and have built-in playmates for life.
- Shared milestones: Twins share many milestones together, such as learning to walk and talk, which can be very special for parents to witness.
- Efficiency: With two babies, parents can often be more efficient with feeding, napping, and other tasks, as they can take care of both babies at the same time.
- Strong support system: Twins can provide each other with a strong support system throughout their lives, which can be especially helpful during challenging times.
Does Genetics Affect the Chances of Twins with donor eggs?
Yes, the genetic background can affect the chances of twins with donor eggs. The likelihood of having twins is influenced by several factors, including age, familial history, and medical interventions such as fertility treatments. However, there is also evidence to suggest that certain genetic factors can increase the likelihood of having twins.
For example, certain ethnic groups, such as African Americans and Central Africans, have a higher incidence of delivering twins. Additionally, women who have a family history of twinning are more likely to conceive twins themselves.
Furthermore, studies have shown that some genes may increase the likelihood of having twins. For example, the gene responsible for producing follicle-stimulating hormone (FSH) has been linked to twinning. Women who carry a specific variant of this gene may have a higher chance of releasing multiple eggs during ovulation, which can increase the likelihood of having fraternal twins.
It’s worth noting that the genetic contribution to twinning is complex and multifactorial, and other factors such as environmental and lifestyle factors can also play a role.
To expand further, there are two types of twins: identical (monozygotic) and fraternal (dizygotic). Identical twins occur when a single fertilized egg splits into two embryos, while fraternal twins occur when two separate eggs are fertilized by two different sperm.
The likelihood of having identical twins is generally considered to be a random event and not influenced by genetics. However, the likelihood of having fraternal twins can be influenced by genetics, as well as other factors such as age and fertility treatments.
Research has identified several genes that may increase the likelihood of having fraternal twins. For example, variations in the genes that control the release of FSH and luteinizing hormone (LH) can affect the number of eggs that are released during ovulation, increasing the likelihood of fraternal twinning.
Additionally, a recent study published in the American Journal of Human Genetics identified a gene called FSHB, which is responsible for producing FSH, as being associated with an increased risk of fraternal twinning. The study found that women who carried a certain variant of the FSHB gene were more likely to have fraternal twins.
It is important to note that genetics is just one factor that can influence the likelihood of having twins and as we mentioned there are other factors that can also play a role. You can also read about the chances of having twins with surrogacy as another assisted reproductive technology.
Generally, the success rate of IVF with donor eggs is very high. In the end, we should say while certain genetic factors may increase the likelihood of twinning, they do not guarantee that twins will be born. If you would like to have a free personal consultation with our doctors, do not hesitate to contact us on WhatsApp now!
