Singles Or Twins With ART?
Assisted reproductive technology (ART) is an innovative set of medical procedures that help individuals or couples conceive. This is the gold standard for infertility challenges or difficulties conceiving naturally. ART involves handling eggs, sperm, or embryos outside of the body. The reproductive materials are then transferred to a woman’s uterus to initiate pregnancy. In vitro fertilization (IVF) is perhaps the most popular method of ART used today. During the process, couples can choose to implant a single or multiple embryos. The embryo transfer method can influence the woman becoming pregnant with a singleton or twins. Understanding the pros and cons can help with more confident ART choices.
IVF and embryo transfer
IVF involves creating multiple embryos from egg and sperm samples harvested from a couple. Some cases require donor eggs or sperm provided by a bank or known person. An embryologist will create the embryo, and over several days, the embryo is ready for transfer. The woman will take hormone medication to develop multiple follicles and to prepare the uterine lining to receive the embryo. At this point, the clinic will perform a single embryo transfer (SET) where the most viable embryo is used. In other words, the fertility clinic uses only 1 embryo per IVF cycle. Multiple embryos, mainly 2 or more viable options, are placed in the uterine lining during a single IVF cycle. This process was common in the initial years of IVF but has lost favor to SET.
One versus two
The embryo transfer process is dictated by the possibility of creating multiple pregnancies and the challenges associated with this consequence. A single embryo significantly reduces the risk of multiple pregnancies while maintaining good success rates. Fertility clinics have become more capable and accurate in developing embryos, increasing the possibility of creating a single, high-quality option. Transferring 2 or more embryos will increase the chances of multiple births. Some couples or individuals prefer a single child at a time and are unable to raise multiples. This approach can also lead to complications for both the mother and the growing children. However, certain situations may call for attempting a multiple embryo transfer.
Factors to consider with embryo transfer
A single embryo transfer is ideal for younger patients with good-quality embryos. These individuals may have a healthy ovarian reserve or have the time to try multiple SETs. If a woman has an underlying health condition or may have potential trouble carrying multiples, a SET is best. Placing 2 or more embryos may still be considered in older couples who are not opposed to multiples due to a closing reproductive window. Some clinics may try multiple embryos if there have been numerous failed IVF cycles. Some initial studies show that multiple embryos have high success rates compared to SET. Now, thanks to advancements in treatment, SET has the same success rates, if not better, in some cases.
Make the right decision
In almost all cases, doctors suggest a single embryo transfer for safety reasons. Implantation rates are still high due to improved embryo handling and quality. Techniques like preimplantation genetic testing (PGT) increase the likelihood of a successful pregnancy. Two or more embryos mean an increased risk of twins or multiples. While some patients welcome the idea of multiples, the risk of premature births, birth complications, and even neonatal death is high. The birth mother is also at risk, so this option must be closely considered and monitored. One of the brilliant benefits of ART is the freedom of choice. Consider all health, lifestyle, financial, and implantation risk factors and move forward confidently with a single or multiple egg transfer.
