Cryotransfer in the natural cycle allows women to conceive a child artificially, who do not have problems with the menstrual cycle. Usually, in this case, the causes of non-occurrence of pregnancy, subject to attempts at natural conception during the year, are diseases of other organs and systems, and not reproductive. As for men, there is only one indication for IVF: poor sperm quality.
The essence of the procedure
Most often, the procedure is performed after an unsuccessful IVF, if the replanting of live embryos ended in failure. According to statistics, cryotransfer in the natural cycle ends with successful implantation of the embryo only in 30% of cases (for comparison: the success of IVF with "live" cells in women under 30 is 50%).
However, some doctors claim that when using frozen cells, the chance of success of the procedure is significantlyrises. There is some truth in this, because for cryotransfer in the natural cycle, by default, only very high-quality biological material is used. In addition, if a woman ovulates naturally, scheduled cryotransfer allows you to wait for that moment, rather than administer stimulation.
During the procedure, from one to four eggs are implanted into the body. Of the indicated number, any number of cells can take root or not one takes root. If, as a result, several embryos have successfully taken root, then, for medical reasons and the desire of the woman, a certain number is removed and frozen. If IVF is not successful, frozen embryos can be transferred at the next attempt.
Cryotransfer of embryos in the natural cycle does not require additional stimulation of the woman's body for the onset of ovulation. Doctors are just waiting for the right moment. There is also no need to re-donate sperm to a partner. As a result, the whole procedure takes less time, and the body experiences less stress.
Preparing embryos
Cryopreservation is the freezing of embryos in liquid nitrogen at a temperature of -196 degrees Celsius. Long preservation or fifteen minutes is used. In the first case, the freezing temperature rises gradually, in the second, the embryos are quickly frozen and quickly thawed. Fifteen minute cryopreservation is more effective. At the same time, more than 80% of fertilized cells survive.
It is important to properly thaw the biological material. After the procedure, the embryologist assesses whether the embryos are damaged during defrosting. In most cases, up to 50% of the cells are lost. But this can be corrected at the initial stage of the procedure, so there will be no harm to the he alth of the fetus. Statistics show that in 5% of cases, embryos after defrosting are completely non-viable.
Steps of cryotransfer
The natural cycle cryotransfer procedure for a patient is not much different from conventional IVF. Preparation begins with a complete medical examination (a general and gynecological history is collected, a series of tests are performed) and treatment, if necessary. As soon as the patient enters the IVF protocol, the doctor monitors her condition in dynamics to determine the optimal day for embryo transfer.
A woman discusses all the conditions of the procedure with a doctor. In most cases, ultrasound of the uterus and appendages is prescribed on the 20-24th day of the cycle preceding the cryotransfer. The reproductologist does dopplerometry to determine how well the blood supply to the vessels and endometrium is carried out. Additional examinations and consultations of narrow specialists are scheduled if necessary, for example, if a woman has already experienced one or more unsuccessful attempts.
In the natural cycle, stimulation is not used, that is, you do not need to take special medications. Tablets may be prescribed if the native endometrium is not ready for implantation. In this case, the drugs will increase the chances ofthe onset of pregnancy. The transfer of five-day-old embryos is carried out on the day of ovulation under ultrasound control. Previously, the embryos undergo defrosting and the necessary preparation (the state of the cells is assessed by the embryologist).
Choosing the day for cryotransfer
On what day will cryotransfer in the natural cycle be most successful and lead to pregnancy? The best day for replanting is calculated by the reproductive specialist. Usually, an increase in the follicle is monitored by ultrasound in dynamics. When the follicle reaches the pre-ovulatory size, the woman does an ovulation test. If the result is positive, then the luteal phase of the menstrual cycle is further supported by progesterone. In parallel, the dynamics of endometrial maturation is being monitored.
When calculating the optimal day of cryotransfer in the natural cycle (on which day the procedure is scheduled, it is impossible to know in advance - all indicators are monitored in dynamics), a complete history, the patient's age, the number of eggs that will be ready by the approximate date of ovulation are taken into account. If there have already been unsuccessful IVF or cryotransfers in the past, then the reproductologist pays attention to how they went. Usually five-day-old embryos are implanted (on the fifth day after ovulation). In some cases, three day old embryos can be transferred.
Preparing for the procedure
Preparation for cryotransfer in the natural cycle is a regular visit to the supervising doctor and the implementation of all recommendations, passing diagnostic and otherpreparatory procedures, testing. If necessary, a woman is prescribed special drugs to build up the endometrium layer necessary for successful attachment and prolong the ovulatory phase. No other special training is usually required.
Carrying out the procedure
Embryos are thawed a few hours before being implanted into a woman's uterus. Cells gradually come to life when they are brought to the required temperature. Next, the doctor evaluates the quality of the thawed embryos. If some embryos do not contain living cells, they cannot be transferred. This happens quite rarely, because embryos with good morphological parameters are usually used for cryopreservation.
Thawed embryos before the procedure are subjected to a procedure that facilitates the process of hatching from the surrounding shell. This can be done chemically or mechanically.
Directly cryotransfer in the natural cycle is performed under sterile conditions under ultrasound control. This is a painless procedure, but the woman may experience some discomfort. The transfer is carried out with a moderately full bladder. The reproductive specialist specifies the position of the uterus, the length of the cervical canal, the angle between the cervix and the uterus, and other data. Optimally, the embryo should be transferred into the cavity 15 mm from the bottom.
When using speculums, the cervix is exposed and flushed with sterile saline to remove mucus. Next, entera special catheter to the level of the internal os of the uterus. Once the catheter guide is in place, embryos with transport medium and gas bubbles are collected into the transfer catheter. By pressing the piston, the embryos are transferred to the uterine cavity. This moment can be seen on the ultrasound screen. After the procedure, the patient should lie down for an hour. On the fourteenth day after cryotransfer, a woman donates blood for hCG to determine if pregnancy has occurred.
After cryotransfer
After cryotransfer in the natural cycle of a woman, you need to follow all the doctor's recommendations. The patient should not be physically tense and nervous, she should try to draw only positive emotions from the environment, rest and get enough sleep more often, be surrounded by people close to her heart. It is not recommended to take a shower and sit in a hot bath (a warm hygienic shower is allowed, the duration of which should not exceed 10 minutes). You can not carry weights, drive a car, bend over sharply, live a sexual life. The patient is advised to eat right and avoid tight and tight clothing.
After the procedure, the patient may experience the following sensations: nausea, bloating, indigestion, drowsiness, pulling sensation in the lower abdomen immediately after cryotransfer. These are symptoms that indicate the natural hormonal changes in the body in connection with the onset of pregnancy. If the stomach "pulls", you need to see a doctor. Most likely, the doctor will advise you to exclude any stress factors, drink sedatives before going to bed, sleep for at least eight hours, walk daily onfresh air at a leisurely pace for two hours.
Pros and cons of the procedure
The patient usually does not experience any pain during cryotransfer in the natural cycle. The procedure itself is painless, and the absence of the need to take strong hormonal drugs allows you to maintain normal he alth. In addition, there is no risk of overstimulation and premature ovarian aging.
Storing embryos frozen usually does not affect the condition of future fetuses. In addition, the embryos used for cryotransfer are of higher quality, so the success of the procedure is higher. If the procedure fails, the next IVF does not require an ovarian puncture.
The disadvantages of the procedure include the need to incur high costs associated with storing the embryo in proper conditions. In addition, there is a small percentage of cases (5%) of the death of all embryos after defrosting.
Forecast of the result
Statistics show that getting pregnant is obtained after the transfer of the third embryo. The success of the procedure largely depends on the professionalism of the doctors, the equipment used and the quality of the embryos. Today, thanks to the cryotransfer procedure, many children are born. These babies are no different from naturally conceived babies.
Patient testimonials
Feedback on cryotransfer in the natural cycle of a woman is positive. Many couples managed to become parents aftermany unsuccessful attempts to conceive, and even with serious problems with reproductive he alth.
