Nowadays, Frozen Embryo Transfer or FET is suggested for IVF/ICSI treatment as providing more pregnancy rate than FRESH embryo transfer.
What is the difference between FRESH VS FET?
– FRESH embryo transfer is the process of embryo transplantation into the uterus after the process of fertilization (IVF/ICSI) for 3 – 6 days.
– Frozen Embryo Transfer (FET) is the process of embryo transplantation into the uterus after thawing frozen embryo. The patient can choose FET date by convenient time e.g. 3-4 months after the oocyte collection date.
Why FET provides more success rate?
- NO OHSS
Most of medications in the ovarian stimulation process are female hormone such as Luteinizing Hormone (LH) and Follicle Stimulating Hormone (FSH) for activating the oocyte. In between stimulation process, not only hormones are rising but also lead to the Ovarian Hyperstimulation (OHSS). OHSS is the situation that the ovaries are too affected than the natural cycle. If the patient make decision to transfer embryo after the ovarian stimulation process (FRESH cycle), they may experience edema, flatulence, hard breathing, acute renal failure and lethal effect.
- More readiness
In the process of the ovarian stimulation also related to the endometrial thickness. Some of the patient experience bloated endometrium and this also affect to the embryo implantation. Frozen Embryo Transfer (FET) is the better suggestion, since the patient can keep their embryo(s) as freezing and come back for embryo transfer after recovering themselves.