IVF treatment is the most commonly preferred assisted reproduction technique for the couples who cannot have children by natural means.1 The vast majority of the basic stages necessary for the formation of pregnancy in IVF treatment (In Vitro Fertilization), are performed outside the body in a laboratory environment, under controlled conditions.
In IVF treatment, hormone therapy is applied to obtain more than one egg from women, and maturing egg cells are harvested. Sperm and egg cells taken from the couple are brought together in a laboratory environment. The resulting embryos are transferred directly to the uterus or are frozen, to wait for the appropriate time for treatment. The fertilization, which under normal conditions occurs in the female body as a result of sexual intercourse, is thus transferred to the laboratory environment.2
In IVF treatment, while the egg cells taken from the woman and the sperm cells taken from the men can combine and form the embryo without any intervention, in some cases, the best quality sperm must be injected into the egg by microinjection method for the formation of the embryo. This method, which is called intracytoplasmic sperm injection (ICSI), is often preferred for the couples with male induced infertility problems.
IVF treatment can be applied in many cases of infertility. One of the most important reasons why this treatment is preferred at such a high rates is that it can give results in cases of infertility caused by both men and women, or in the case of infertility whose cause cannot be determined.
The wide scope of the treatment and the fact that it can be a solution to many different causes of infertility increases the importance of the answers to the queston “Who can have IVF treatment?".
Before going into details about who can be treated with IVF and in what cases, it is necessary to know the process of pregnancy in order to better understand the function of the treatment.
The formation of pregnancy by natural means is an extremely complicated process. The most basic condition of pregnancy is that healthy and high quality egg cells and quality sperm cells can come together and embryo formation occurs as a result of this union. Many different elements are effective behind these outlined stages.
Under normal conditions, one egg is lost from the egg reserves of women every month and begins to progress through the female reproductive system, maturing for the formation of pregnancy. Although ovulation is one of the basic conditions of pregnancy, the released egg cell must proceed through the fallopian Tubes. Structural disorders or blockages in one or both fallopian tubes can stop the progression of the egg. Even if sperms can reach the region and fertilization takes place, pregnancy cannot develop properly.
Another indispensable requirement of pregnancy is that the sperms that come out of the male body with semen during ejaculation must progress towards the egg. For this progress, spermatozoa must be in sufficient numbers and ideally shaped. It is important that they can move forward at the ideal speed. Sperm that manage to reach the uterus should be pulled towards the fallopian tubes by contractions that occur in the uterus.
After ovulation occurs, the egg cell must be fertilized within a 12 - 24-hour period. Fertilization usually occurs in the large part of the tube, called the ampullary - isthmic connection. When sperm enters the egg cell, cellular division begins. A single-celled formation called a zygote turns into an embryo by mitotic division. The embryo continues to move towards the uterus.
Around 5-6 days after the fertilization, the embryo reaches the blastocyst stage and begins to settle in the uterus. Implantation bleeding, also known as settlement bleeding, can occur during the implantation of the embryo into the uterus. This process is controlled via hormones.3
A problem experienced at any of these stages can prevent the occurrence of pregnancy by natural means. Many reasons such as not being able to determine the time of sexual intercourse correctly, ovulation not occurring, fallopian tubes being blocked, and the embryo not being able to attach to the uterus can cause infertility.
Many reasons that prevent the occurrence of pregnancy by natural means may require resorting to IVF treatment.
Based on all this information, the following cases are good candidates for IVF treatment:
In case of diagnosis of infertility whose cause cannot be determined, in case of recurrent miscarriages and if one or both couples posses a genetic disorder, IVF treatment can be considered.5
IVF treatment can also be performed if one of the couples will undergo cancer treatment. Radiotherapy and/or chemotherapy can lead to infertility for both men and women. In this case, sperm freezing, egg freezing, ovarian tissue freezing or embryo freezing treatments may be performed.
1 https://www.yalemedicine.org/conditions/ivf
2 https://www.hfea.gov.uk/treatments/explore-all-treatments/in-vitro-fertilisation-ivf/
3 https://www.ucsfhealth.org/education/conception-how-it-works
4 https://www.nhs.uk/conditions/ivf/
5 https://www.mayoclinic.org/tests-procedures/in-vitro-fertilization/about/pac-20384716
