Surrogacy is a meaningful path for people who want to raise children but cannot do so on their own. If you are considering it, whether as an intended parent or a surrogate, the odds of success are usually one of the first things on your mind.
At the Surrogacy Center of Philadelphia, surrogacy success rates are among the questions we hear most. We answer them honestly, and we take time to explain the factors that actually shape the outcome, so you can make decisions with a clear picture rather than a guess.
Here are the numbers we see in practice. On average, about 60 to 65% of first embryo transfers result in a live birth. This holds fairly steady across first-time and experienced surrogates and across the clinics we work with in the Greater Philadelphia region. When a first transfer does not succeed, the second often does, and roughly 80% of surrogates are pregnant within two transfers.
You may see these described in different ways online, as an embryo transfer success rate or an IVF surrogacy success rate, but they all describe the same funnel: the odds per transfer, and the higher odds once you allow for a second attempt. The single biggest driver behind those numbers is embryo quality, followed by the surrogate’s health and the clinic’s protocol. Here is how each one works.
The process starts with intended parents who want to grow their family but cannot carry a pregnancy themselves. They partner with a woman who agrees to carry for them, known as a gestational carrier or surrogate.
Surrogate candidates meet strict standards, and ours are among the strictest in the country, for the safety of both the baby and the carrier. Once under contract, the surrogate completes a treatment cycle at the fertility clinic, an embryo created by the intended parents is transferred to her uterus, and she carries the pregnancy to a healthy delivery. You can read more about what we look for on our surrogate requirements page, and about the full journey on our services for intended parents page.
Surrogacy is a meaningful path for people who want to raise children but cannot do so on their own. If you are considering it, whether as an intended parent or a surrogate, the odds of success are usually one of the first things on your mind.
At the Surrogacy Center of Philadelphia, surrogacy success rates are among the questions we hear most. We answer them honestly, and we take time to explain the factors that actually shape the outcome, so you can make decisions with a clear picture rather than a guess.
Embryo quality is the primary determinant of success. During IVF, the clinic retrieves multiple eggs from the intended mother or an egg donor. Not every egg is usable; the average attrition rate is around 15 to 20%. The rest are fertilized with sperm from the intended father or a donor.
On average, 70 to 80% of eggs fertilize successfully. Of those, only about half reach the blastocyst stage, the Day 5 or 6 embryo that is transferred to a surrogate. Clinics grade these embryos on how the cells are expanding, the quality of the inner cell mass, and the membrane that will surround the baby. You may see your embryos labeled something like “5AA” or “4AB.” Do not be discouraged by less-than-perfect grades. Many healthy babies come from average embryos.
Intended parents can also choose pre-implantation genetic testing, or PGT, which biopsies the embryo to check for chromosomal issues. PGT-normal embryos tend to produce excellent transfer success rates.
The surrogate’s health is the second major factor. We require surrogates to be between 21 and 42 years old. Pregnancy carries more risk as a woman gets older, and safety for both surrogate and baby is always our first priority.
Surrogates should be in good physical health, generally with a BMI in the range our medical team looks for, since the hormone medications used in a transfer cycle are harder to manage at higher weights and pregnancy risks rise. Not every chronic condition is an automatic disqualifier. Most agencies, including ours, also ask that a surrogate has already delivered at least one healthy baby with no history of pregnancy or delivery complications, since past pregnancy is one of the best predictors of a smooth one ahead.
The third factor is the clinic itself. Fertility clinics use different medications, dosages, and timelines to prepare the uterus to receive an embryo. Working with a clinic experienced specifically in gestational carrier cycles, not just standard IVF, makes a real difference.
It is worth asking a clinic how they handle a failed transfer. Do they simply repeat the same protocol, or do they investigate uterine receptivity and adjust the medication or its dosage? A clinic that learns from a first attempt gives your second transfer better odds.
For a surrogate, the embryo transfer is the moment the journey becomes real, and it is natural to feel some nerves. The transfer itself is quick and does not require anesthesia. In the weeks beforehand, you will take fertility medications to prepare your uterus, with regular monitoring of your hormone levels until everything is ready.
After the transfer, the clinic confirms pregnancy with blood tests, and a fetal heartbeat is typically confirmed by ultrasound at around four to six weeks. From there, care transitions to your regular OB, and the pregnancy proceeds like any other.
Good embryos, a healthy surrogate, and an experienced clinic together give any journey its best chance. If you have questions about success rates as you think through surrogacy, we are glad to talk them through with no pressure.
You can learn more about the numbers side of a journey on our surrogacy cost and surrogate compensation pages, or schedule a consultation to talk through your own situation.
