Term “IVF” is abbreviation of words “in vitro fertilization”. From Latin these words mean “outside body”, that is, fertilization, which takes place outside the body of a person, or in vitro.
Today, it is one of the high-tech methods of infertility treatment, when fertilization in natural conditions, due to any reasons, is impossible. The most common reason of infertility is blocking of uterine tubes or their absence. In this case, sperm can’t get to ovum and fertilize it.
To conduct fertilization in vitro, it is necessary to receive healthy ovums and sperm, unite them in a test tube, and then move the resulting embryo into the alvus for further development.
Other kinds of infertility, when IVF method can be effective:
- Infertility due to tubal-peritoneal factor (adhesive process in the abdominal cavity);
- due to endometriosis of any form and stage;
- due to endocrine factors (lack of ovulation of any origin);
- due to male and immunologic factor (a large number of antibodies against sperm in blood of women or men);
- due to idiopathic infertility (infertility of uncertain origin, when all tests were made, but the reason is not found out).
First stage of IVF procedure
It is a preparatory stage to the IVF procedure. A married couple undergoes tests and preparation for the in vitro fertilization. These medical examinations married couple can make at place of residence.
Second stage of IVF procedure
During this phase monitoring of growth and maturation of follicular is carried out. Since this moment, treatment is started. During this stage, induction of superovulation (that is, stimulation of maturation of several ovums during one menstrual cycle) is conducted. For the successful implementation of IVF procedure it is needed to get several ovums during one menstrual cycle. It is possible to receive such possibility, which provides more chances for the successful result, with the help of hormonal drugs. These medications help to control the course of menstrual cycle and with the utmost precision calculate the time of ovums’ maturation.
Women in the age of under 40 years old, as a rule, are included in the treatment cycle since 17th-21st day of the menstrual cycle, that take priority of stimulation cycle (induction of superovulation). From this time, doctors begin introduction of drugs, which prepare oothecas for stimulation. Since 1st-3rd day of the next menstrual cycle drugs are used, they directly stimulate growth and maturation of follicles, as well as, growth of endometrium – internal layer of alvus, where, further, embryos will be implanted. Women older than 40 years started the treatment cycle since the 1st day of menstrual cycle, during which stimulation of oothecas, with the use of mentioned above drugs, will be held.
Follicles’ growth and maturation of ovums
these indexes are estimated at this stage, with the help of ultrasonic (on indications) hormonal monitoring. All procedures are undertaken out patiently.
Third stage of IVF procedure
Puncture or aspiration of follicular fluid, which contains ovums. Puncture of follicles and ovums’ samplings – this is operation that can be performed in two ways.
the front abdominal wall (transdominationaly) with laparoscopy, requires hospitalization, and is performed under General anesthesia and today this method is used very rarely.
transvaginal, when oothecas’ puncture is carried out through the vagina using a special needle under control of ultrasonic examination. Because of its minimal trauma level and painfulness transvaginal method of oothecas’ puncture is more convenient for patients; it is performed on an outpatient basis with anesthesia at the request of patients. On the day of puncture, both mates visit medical center.
Fourth stage of IVF procedure – embryological
Received, during the puncture, ovum’s follicles are placed in special cups with growth medium. Then this cup is placed in incubator, where conditions similar to those in mother’s organism are created (exactly the same temperature and content of carbon dioxide, oxygen). At the time when ovums are in incubator husband donate sperm. The obligatory condition is a pre abstinence from sexual life within 3-5 days. For most men, after 3-day abstinence composition of sperm and its quality are the best ones. Spermatogenesis, in many respects, depends on influence of unfavorable factors. Sperm’s quality declines much under the influence of nicotine, alcohol, occupational harmful conditions, stress situations, due to nervous and general over fatigue, acute and chronic diseases. When treatment planning in medical IVF centre, it is necessary to exclude influence of harmful factors or minimize them and their influence. It is necessary to remember, that composition of sperm is completely updated during a period of three months. Therefore, the longer man managed to keep a healthy way of life the better will be a result.
Only one sperm cell of dozens of thousands is needed for fertilization of one ovum.
After unification of germinal vesicle stage of zygote’s formation is started. As a rule, in 24 hours after combination of ovum and sperm, it can be seen the first splitting of zygote and stage of 2-blastomere or 2-cell embryo is started. Stage of 2- 4-8 cell embryos is considered to be optimal for the embryos transfer into the uterine cavity.
Fifth stage of IVF procedure – transfer of embryos into the uterine cavity
Transfer of embryos is carried out in 48-72 hours with the help of special catheters. However, in some cases, transfer can be done at later stages, up to formation of morula or blastocyte stage. It is recommended to carry not more than 3-4 embryos in the uterine cavity, because when transferring larger number of embryos there is possible implantation of 2 or more embryos. After embryos’ transfer woman gets sick list with a diagnosis of “Early pregnancy, threatened miscarriage “. The sick list is given for 14 days, i.e. till the primary pregnancy testing.
Sixth stage of IVF procedure – pregnancy testing
In two weeks after embryos transfer into the uterine cavity diagnosis “biochemical pregnancy” can be fixed by the level of chorion gonadotrophic hormone (CG) in blood, which is produced by gestational sac. This method is more sensitive than a qualitative method of CG determination in urine. In 3 weeks it is possible to see a gestational sac in uterine cavity with the help of ultrasound.
Success of IVF procedure depends on many factors: age of marrieds, response to stimulation of oothecas, quantity and quality of sperm, nature, causes and duration of infertility. Often outcome of procedure cannot be explained from the position of modern science. IVF procedure requires patients to have more patience, discipline and strictly observe all prescriptions and recommendations of doctor.
Carrying out of the IVF procedure is a risk to have certain complications, associated with the induction of superovulation (stimulation), ovums’s getting, and also connected with the pregnancy begging.
Complications associated with induction of superovulation
Generally, during the process of IVF procedure doctors use drug-induced superovulation’s stimulation to achieve multiple follicular’s development. Schemes of superovulation stimulation can be different; doctor chooses an appropriate one and shares this information with patients. While conducting superovulation’s induction it can be obtained both weak response of oothecas (3.1 maturing follicles) and excessive ovarian response to hormonal stimulation (increase of more than 10-15 follicles). During weak response probability of getting a sufficient number of quality embryos is decreased, due to this process of pregnancy is reduced. During excessive ovarian response, it can be complication of superovulation’s induction in IVF program, in particular ovarian hyperstimulation syndrome (OHSS), which is characterized by a wide spectrum of clinical and laboratory symptoms. Frequency of moderate and hard form of OHSS of women who are being treated by methods of assisted reproduction is 3-4%, and 0.1 and 0.2%, respectively.
Patients with moderate OHSS need serious monitoring (sometimes in hospital) and timely treatment, as clinical picture can rapidly progress to hard forms, especially in the case of pregnancy. Patients with hard form of OHSS require immediate hospitalization and emergency care. Treatment of this complication is accompanied by additional material costs.