Frozen embryo transfer (FET)

In IVF, stimulation and egg retrieval produce embryos in the lab. In a frozen embryo transfer, those embryos are cryopreserved and a single one is thawed and transferred in a later cycle, rather than transferred fresh in the same cycle as the retrieval. An embryo can be frozen for years and thawed when the timing is right, which is what makes a second or third attempt from one retrieval possible without stimulating again. Until then they sit in storage, which clinics bill by the year: what US clinics charge to store embryos.

This is now the default. Most US embryo transfers are frozen rather than fresh, a reversal from a decade ago, because freezing lets the body recover from stimulation before the lining receives an embryo, and modern fast-freezing (vitrification) preserves embryos with very little loss. A "freeze-all" cycle freezes every viable embryo and plans the transfer for a later, unstimulated cycle.

Whichever route you take, the number that moves outcomes most is age. National live-birth rates run from about 49.7% per intended egg retrieval under 35 to 7.7% over 40 (CDC, patients using their own eggs). See the full by-age and per-clinic breakdown, and why a "per transfer" rate looks higher than a per-retrieval one, on our success rates page.

A price counts only when the clinic's own website states it as its price. A general figure such as "an FET typically costs $3,000 to $5,000" does not, nor does an IVF package that merely includes a transfer, nor an old price list the site no longer links. A clinic missing here may still offer FET; ask for a written quote that says whether monitoring, medications and the thaw are included. Embryos also carry a yearly storage fee until they are used.

1. 1
   Cycle preparation and suppressionabout 3 to 4 weeks

   Daily birth-control pills suppress the normal ovarian cycle so the transfer can be scheduled precisely, rather than around your natural cycle. Source

2. 2
   Estrogen to build the liningabout 10 days

   Estrogen thickens the uterine lining. In a typical protocol an ultrasound and bloodwork lining check, around day 10, confirms the lining has thickened and hormone levels are right before progesterone is added. Source

3. 3
   Progesterone, then the transfertransfer 3 to 5 days after progesterone starts

   Progesterone prepares the lining to accept an embryo and sets the transfer day. It starts 3 days before a cleavage-stage transfer or 5 days before a blastocyst transfer, and the thawed embryo is placed with a thin catheter in a quick, usually painless procedure that needs no anesthesia. Source

4. 4
   Pregnancy testabout 10 to 14 days after transfer

   A blood test measures hCG to confirm pregnancy. Progesterone support usually continues into early pregnancy (typically until 8 to 12 weeks) if the test is positive. Source

A natural-cycle FET skips most of this medication and times the transfer to your own ovulation, which suits patients with regular cycles. A medicated cycle trades more medication for precise scheduling and control.