Our Pregnancy Rates
Pregnancy rates for the NYU Langone Fertility Center are available from the Society for Assisted Reproductive Technology (SART). Below is information that can help you better understand the report.
Guide to Reporting Terminology
Statistics from the Fertility Center relate to in vitro fertilization (IVF) cycles using fresh and frozen embryos. The statistics reported to SART include the following:
- Cycles using fresh embryos created from a woman’s own eggs. These include cycles where a woman's eggs are harvested and fertilized in our laboratory and one or more of the freshly created embryos are returned to the uterus during the same IVF cycle.
- Cycles using frozen-thawed embryos created from a woman’s own eggs. These include cycles where eggs are retrieved from a woman and fertilized with sperm, and then the embryos are cryopreserved and subsequently thawed and transferred into the same woman’s uterus. These cycles often include preimplantation genetic screening or diagnosis (PGS or PGD), which requires the freezing of embryos after biopsy as we await test results. Because PGS and PGD screening increases the chances of a successful pregnancy, success rates in this group can be higher than those reported for fresh IVF transfers.
- Cycles using donor eggs. Donated eggs come from another woman. Donated eggs can be fertilized with sperm and used either fresh or in a subsequent cycle after being frozen and thawed. Donated eggs can also be stored unfertilized and thawed at a later date to be fertilized and transferred to the intended mother’s womb. These are called “banked” donor eggs. Donor embryos are also sometimes used to create pregnancy. These embryos are donated by a woman or couple for use by another person or couple.
Cycles in which a woman’s own banked eggs are frozen, thawed, and fertilized are not included in the SART statistic groups reported above. Please note, however, that SART is revamping the reporting format to reflect recent advances in fertility treatment options and technologies and they will be included soon. The new report is scheduled to be available starting in 2016.
Age is one of the primary factors affecting a woman's chances for success with any fertility treatment. The probability of having a child naturally begins to diminish somewhere between the ages of 28 and 33, falls more precipitously between the ages of 35 and 40, and continues to decline thereafter. By age 45, most women are no longer able to achieve pregnancy without the use of their own or another woman’s younger oocytes. On the same timeline, the chance for miscarriage increases.
Understanding Assisted Reproductive Technology Statistics
As a member of SART and the American Society for Reproductive Medicine, the NYU Langone Fertility Center reports its assisted reproductive technology (ART) outcomes annually.
ART cycle outcomes are measured in a variety of ways, so it’s important to understand the statistical subtleties when comparing one clinic's success rates to others. The reported outcomes relate only to in vitro cycles and do not reflect additional live births that result from other infertility therapies, such as artificial insemination and ovulation induction using fertility medications.
A program's pregnancy success rates vary depending on the methodology used for reporting outcomes and the specific technologies used within the clinic. Because statistics are collected at different stages of an ART cycle, and a cycle may divert from traditional IVF or, alternatively, fail at various points along the way, successes reported at one stage may not reflect success at another stage.
Live Births per Egg Retrieval
ART cycle live-birth outcomes are reported three ways: per initiated treatment cycle, per egg retrieval, and per embryo transfer procedure. The analysis of live births per initiated cycle provides the percentage of live births occurring for patients that begin ART treatment. Data reported per egg retrieval and per embryo transfer provide outcomes for cycles where the egg extraction and embryo transfer procedures are completed.
The reported live-birth percentage per egg retrieval is often higher than that per initiated cycle, because sometimes a treatment cycle is started but the ovaries do not respond sufficiently, resulting in cycle cancelation due to low egg number. On the other hand, the reported percentage of live births per embryo transfer can be higher than per egg retrieval, because some treatment cycles don’t result in embryos suitable for transfer.
In addition, preimplantation genetic screening is now commonly used at some clinics, including our own, at the end of an IVF cycle attempt. The embryos are now almost always frozen before transfer. Thus, any cycle using preimplantation genetic screening is reported in the frozen embryo data columns rather than in those for freshly created embryos. These cycles are not differentiated from traditional frozen cycles, where preimplantation genetic screening was not used. This can make comparisons of fresh and frozen cycle data from a given clinic or between clinics difficult.
It’s important to keep in mind that at even the best of centers, only a percentage of initiated ART cycles result in pregnancy, and even fewer in a live birth.