Frozen embryos offer patients who are suffering from infertility problems, an opportunity to expand their families in the future. There is no decline in embryos quality while they are in frozen state, therefore it maintain their reproductive potential. The embryos are associated with the age of the woman’s egg at the time of its fertilization; this can be an additional advantage. If a 35 years old patient goes through a full IVF cycle, she will be using eggs from her 35 years old with subsequent FET’s at the age of at 37 and again at 39. Younger eggs result in higher chances of chromosomal normalcy and higher pregnancy rates, so younger eggs are always preferred.
Women suffering from polycystic ovary syndrome (a hormonal disorder that often leads to fertility problems) can improve their chances of a successful pregnancy with the help of frozen embryos rather than fresh ones for in-vitro fertilization. Historically, the use of fresh embryos is preferred over that of frozen embryos, but study suggested that elective embryo freezing followed by frozen embryo transfer is an effective treatment for women with polycystic ovary syndrome. According to the studies, the success behind frozen embryos depends on the fact that frozen embryos take longer than fresh embryos to implant in the uterus. This is necessary for the better fertility environment because it allows hormone levels in the uterus to return to normal before the embryo is implanted. Frozen embryos increases pregnancy success rate in women, additionally women treated with frozen embryos also had fewer instances of hyperstimulation syndrome(a condition in which the ovaries swell and become painful and may also results in other pregnancy complications) than women given fresh embryos. If a woman can able to freeze and store their embryos while attempting a fresh cycle transfer, and if accidently the fresh cycle is unsuccessful, she always has an option to try again without undergoing another ovarian stimulation or egg retrieval. Therefore, her cumulative pregnancy rate increases overall from one IVF cycle. Multiple frozen embryo transfer or FET cycles are less costly than fresh IVF cycle because medication is relatively less and there is no egg retrieval or anesthesia involved in this process. With Single Embryo Transfer or SET there may be an opportunities for multiple FET cycle after just one egg retrieval which again increases the cumulative pregnancy rate from one IVF. FET cycles can be easily scheduled when it is more suitable and convenient for most of women. After scheduling FET, women are prescribed oral estrogen so that the uterine lining become ready for the transfer and this is administered only once every three days. Progesterone injections are applied, so that the women body can able to support a successful pregnancy. Daily intramuscular progesterone can be prescribed later in the cycle.
But at the same time, there are also few risks associated with women who received frozen embryos. It slightly increase risk of potentially dangerous high blood pressure during pregnancy and can increase death rate in newborn babies.