Medical Contribution by Naveed Khan, M.D.

Dr. Naveed Khan of SGF’s Leesburg, VA office.

In the past decade, one of the greatest advancements in fertility treatment has been vitrification. Vitrification is a flash-freeze technology used for freezing eggs and embryos for the purpose of using them at a later date. While cryopreservation had existed to fulfill the same purpose for many years, the process frequently resulted in the formation of ice crystals in the eggs and embryos, often rendering them unusable. Vitrification’s flash-freeze technology, though, has remarkably advanced the freezing process and corrected earlier flaws. “One of the largest benefits of using vitrification has been increasing the success rates when using frozen embryo transfers (FET), as vitrification has doubled the ongoing pregnancy rate per embryo transfer in the past five years,” says Dr. Naveed Khan of Shady Grove Fertility’s Leesburg, Virginia office.

In order to undergo a frozen embryo transfer though, you must first perform a fresh in vitro fertilization (IVF) cycle. Oftentimes, there may be additional unused embryos from a  fresh cycle. This is where vitrification can be used to preserve the embryos for a later date and a patient can eventually return for a frozen embryo transfer cycle.

Who will utilize a frozen embryo transfer (FET)?

A frozen embryo transfer (FET) can be performed by any patient who has frozen leftover embryos from a fresh autologous IVF or donor egg cycle. The use of frozen embryos may come immediately following an unsuccessful fresh cycle, or, for patients who were successful with their fresh cycle, a FET can be used at a later date to have additional children.

What are the benefits of FET in comparison to performing another fresh (stimulated) cycle?

FET is often a good choice over completing another fresh IVF cycle when a patient has frozen embryos to use, as they have a lower cost (see the financial programs section below) and there is no need to have an egg retrieval. “Additionally, the date of the frozen embryo transfer is much more predictable than that of a fresh cycle, as you do not have to wait for the embryos to develop and mature. A FET cycle works much better in terms of planning around the transfer itself,” explains Dr. Khan.

What are the success rates for IVF with FET compared to that of a fresh cycle?

The success rates for FETs have doubled in the past five years, with an ongoing pregnancy per embryo transfer rate equal to – or sometimes even greater than – that of fresh transfers. In 2013, women under 35 had a 51% ongoing pregnancy rate per frozen embryo transfer. In comparison in 2013, women under 35 had a 48% ongoing pregnancy rate per fresh embryo transfer. FET cycles had a slightly higher success rate than fresh cycles, which can happen due to the presence of more balanced hormones and the fact that only high-quality blastocyst-stage embryos are being used for FETs.

How long does a FET cycle take?

A patient will contact our office with her desire to begin a frozen cycle. Her records will be reviewed to ensure that her prescreening is up-to-date. This can include – but is not limited to – infectious disease bloodwork, pap smear, an updated mock embryo transfer (to accurately measure and map your uterine contours), consents, and an injection review.

Prior to the frozen cycle beginning, most patients will be on a cycle/month of oral contraceptives. Soon after, the patient will come in for their first monitoring appointment, which is a baseline evaluation before the medications are started. Patients will then begin sequential injections of estrogen to build the uterine lining. Mid-cycle, the patient will have to have a ‘lining check,’ to ensure that the uterine lining has thickened. Patients will then be instructed to add in progesterone. A frozen embryo transfer date will be confirmed and then the patient will return for her actual frozen transfer. Approximately two weeks after the transfer, the patient will have a blood pregnancy test (known as the beta hCG).