The developments in the field of in vitro fertilization, which is considered to be the only method for many couples to have children, have significantly increased the rate of success for the treatment. Let us take a closer look to these developments that range from a reduction in drug use to cryopreservation of embryos. In Turkey, the history of in vitro fertilization, which allows even for whom it is thought to be impossible to have children, begins over 30 years ago. The method, which was applied in 1978 in England for the first time, was also put to use in Turkey after a short while. The innovations and improvements in the field of in vitro fertilization, which was received with great amazement and has been regarded to be a miracle from the very first day, increase the rate of success for the treatment. Currently, the possibility of having a child through this treatment is over 50%, depending on the mother’s age and ovarian reserve. Professor Faruk Buyru, a gynecologist/obstetrician and head of the In Vitro Fertilization and Reproductive Health Center of Acıbadem Fulya Hospital, has shared with us information on the new application in the field of in vitro fertilization.
The only option on some cases
In vitro fertilization is regarded as the last resort for couples who cannot have children due to certain conditions in the mother or the father, or inexplicable infertility. Stating that, this method, which is the last resort in some cases and the only option in others, was primarily invented as a solution for women with blocked fallopian tubes, and says, “The fallopian tubes constitute the environment in which the sperm and the egg are joined and conception occurs. In the past, specialists tried to open the blocked fallopian tubes through surgery. However, the rate of success for this method was not very high. The method of in vitro fertilization was invented when research on achieving conception outside the body yielded successful results. While the method is mainly regarded as the solution for women with blocked fallopian tubes, it can also be used in unexplained infertility cases and cases in which conception does not occur due to the male factor or other reasons”. In vitro fertilization becomes the first preferable option for women with blocked fallopian tubes and men with low sperm count. The method is also used in cases where artificial insemination does not yield successful results. The ovarian reserve of women starts to decrease after the age of 35 and the rate of decrease becomes higher after the age of 38. Therefore, women who wish to have children are warned against waiting until later ages. Professor Buyru categorizes the innovations in the field of in vitro fertilization under the following sections:
Lower drug doses
Currently, the dose of drugs that are used before in vitro fertilization is lower. It is now known that overstimulating ovaries has certain adverse effects. Production of 8 to 15 eggs is considered to be ideal. Therefore, specialists prescribe a lower number of drugs with lower doses and ensure for the patient to undergo a treatment in which she will have less difficulty. In other words, drug doses and durations of drug use have decreased considerably when compared to the past. Normally, a woman produces one or two eggs per month. One or two eggs can be sufficient for artificial insemination but in vitro fertilization requires at least five or six eggs. In the past, a higher amount of drugs was used. More than one embryo was transferred and this led to multiple pregnancies. It is now known that multiple pregnancies are risky for both mothers and babies.
This method involves placement of embryos in the uterus on the fifth day of development instead of the third, which is the normal procedure. This method is referred to as “blastocyst transfer”. The possibility of an embryo to lead to pregnancy is higher on day five. However, waiting until the fifth day may not be possible for all women. It is essential for specialists to decide on the day of transfer in accordance with the condition of each patient.
Rapid freezing of blastocysts on the fifth day and transfer of these after revival at a later period is associated with possibility of pregnancy as high as that of fresh embryo transfer. Therefore, there are claims that it is better to transfer embryos after one or few months following the stimulation of ovaries instead of transferring these right away. The new method’s popularity increases with each passing day. There are multiple reasons behind this. For instance, it is possible for the potential mother’s increasing hormones to have an adverse effect in the uterus and decrease the possibility for pregnancy. When ovaries are overstimulated, problems such as bloating, ascites (accumulation of fluid in the abdominal cavity), decrease in urine output and coagulation risk arise. In such cases, embryo cryopreservation yields better results. This method protects the woman’s health and is associated with a higher pregnancy rate. It can also be an alternative for families who wish to have children at a later period due to social reasons because embryos remain at the stage at which they are frozen. During the period of cryopreservation, the pregnancy rate continues to be higher in comparison to other methods even if the potential mother becomes older.
Single embryo transfer
The regulations that became effective in 2011 have brought restrictions to the number of embryos that can be transferred to a woman in a single application. The number of embryos that can be transferred is one for women under the age of 35 and two at most for older women. These restrictions are intended to decrease the possibility of multiple pregnancies because multiple pregnancies can result in miscarriages or premature births. Such cases can affect both the babies to be born and the pregnancy period. Therefore, multiple pregnancies are no longer accepted as success in treatment and single pregnancy has become the goal in recent years.
The injections which used to be the norm for application of post-transfer drugs are now replaced by vaginal administration. This is because the progesterone injections that are used after embryo transfer are very painful and inconvenient. Drugs that are administered vaginally and more conveniently are preferred over these.
Before transfer, the genetic structures of embryos are analyzed. Preimplantation genetic diagnosis and screening methods make it possible for healthy embryos to be chosen. This increases the rate of pregnancy. The embryos are screened on the fifth day instead of the third day, which allows for a higher number of chromosomes to be examined.
There are also improvements in the environment in which embryos are developed. These also increase the pregnancy rate. Furthermore, it is possible for embryos to be observed with embryoscopes, through a camera in devices referred to as incubators without having to bring these into normal room conditions. The development of embryos is tracked more closely via photographs and avoiding exposure of embryos to room temperatures on a frequent basis.