Surrogacy Success Rates: Important Facts for Parents and Surrogates
Surrogacy is a wonderful option for people who want the experience of raising children but can’t have children by traditional means. With that said, it’s fair to say that surrogacy costs can run pretty high. If intended parents are willing to go the IVF surrogacy route, success rates will undoubtedly be top of mind.
At the Surrogacy Center of Philadelphia, surrogacy success rates are among the most frequently asked questions. We always answer these questions based on our commitment and obligation to be transparent. At the same time, we seek to educate both the prospective surrogate and intended parents about the factors that ultimately determine the success or failure of IVF surrogacy.
How Does Surrogacy Work?
The process begins with people who want to start or expand their family but cannot do so traditionally. Intended Parents decide to contract and compensate a woman who agrees to be their surrogate, also known as a gestational carrier.
Surrogate candidates must meet stringent standards, and our agency maintains some of the strictest in the U.S. We do this for the safety of the baby being carried and the carrier herself.
Once under contract, the surrogate undergoes a treatment cycle at the fertility clinic, and an embryo created by the Intended Parents is transferred into her uterus. She then continues with the pregnancy and delivers a healthy baby into their parents’ arms.
Factors That Determine Surrogacy Success Rate
An experienced agency like the Surrogacy Center of Philadelphia will have data on success rates. Generally, the quality of the embryo that is transferred into the surrogate is the primary determinant of success. On average, about 60% of first-time embryo transfers result in a live birth. This is consistent across all our surrogates (whether first-time or experienced carriers) and clinics across the Greater Philadelphia Region. If the first transfer is unsuccessful, the second transfer will most often be. As such, about 80% of surrogates become pregnant within two transfers. What else influences success rates besides embryo quality? The other two primary factors to success relate to the surrogate herself and the clinic protocol used.
During the In Vitro fertilization process, the fertility clinic will retrieve multiple egg cells from the Intended Mother or an egg donor. Not all eggs are suitable for fertilization (the average attrition rate is around 15-20%). The remaining eggs are fertilized with sperm from the Intended Father or a sperm donor.
On average, most patients have 70-80% of their eggs that are successfully fertilized. Of those that are fertilized, not all will grow into good-quality embryos. On average, only about 50% will reach the blastocyst stage (a Day 5 or 6 embryo). A blastocyst is the type of embryo that is transferred into a surrogate.
The fertility clinic grades embryos. They look carefully at the different cells which will develop into the baby and its placenta. They’ll look at (1) how the cells are expanding, (2) the inner quality of the cell mass, and (3) the cell membrane that will surround the baby. Intended Parents will receive their grading report and may see that their embryos are a “5AA” or a “4AB” (where each digit/letter refers to the three factors that the embryologist is assessing). We tell families not to get discouraged if their embryos are not perfectly graded. Many healthy babies have been born from “average” embryos.
In addition to grading, Intended Parents can opt for further testing to determine embryo quality. This is called pre-implantation genetic testing or PGT. The embryo is biopsied, and the cells are examined for chromosomal abnormalities. Intended Parents then receive a report showing which embryos are “PGT normal.” In general, PGT normal embryos result in excellent transfer success rates.
Women have peak reproductive years. At our agency, we require the surrogate to be between 21 years old and 40 years old. Why the age limit? Pregnancy becomes riskier as a woman gets older. Safety is always our number one priority for surrogates and their babies.
Surrogates should be physically healthy, with a BMI between 20-32. This is because the hormone medications one takes during a surrogacy cycle cannot be managed as well once the BMI exceeds 32. Additionally, obesity increases the risk of pregnancy complications. That being said, not all chronic medical conditions are automatic disqualifiers.
Almost all agencies require that prospective surrogates have had at least one successful delivery of a healthy baby. They further require that prospective surrogates have no history of problems during pregnancy or delivery. These requirements are in place based on the premise that maternal history is a good predictor of future outcomes.
Fertility clinics use a variety of medications to prep the uterus to receive the embryo. While the medications are similar, the dosages and length of time taking those medications can vary. Working with a reputable fertility clinic with experience with gestational carrier cycles (not just IVF) is important.
Asking the clinic about their approach if a transfer fails is also important. Do they simply repeat the same protocol? Will they do diagnostic work to check uterine receptivity or consider changing dosage or methods of medication administration (ex., injections vs. oral medications)?
We hope you find this information useful as you consider surrogacy as a gestational carrier or intended parent. Having good quality embryos with a healthy surrogate, and working with a reputable clinic, lead to the best success rates. If you have any questions about anything you read, please contact us.