IVF in the natural cycle

IVF in a natural cycle (EC) is one of the most gentle ways to get pregnant. In such a program, drugs are used minimally. The egg is fertilized in the laboratory, but its maturation takes place in the woman’s body.

Today, IVF at the EC is used on a par with the traditional protocol. We understand the intricacies with gynecologists.

Who is shown IVF in the natural cycle

IVF in the natural cycle is recommended for women of different age groups. (one)

The procedure is carried out if:

• there is obstruction of the fallopian tubes (tubal factor of infertility);
• there is male infertility;
• there are contraindications to the use of hormonal stimulation (oncological diseases, problems with the blood coagulation system);
• developed hyperstimulation syndrome in previous IVF protocols;
• in previous protocols with stimulation, there was a weak response of the ovaries to hormonal therapy (only 2-3 eggs matured).

Women with anovulatory cycles (in which there is no ovulation and the phase of development of the corpus luteum) are contraindicated for IVF in the natural cycle.

How IVF works in the natural cycle

The procedure differs from other programs in that there is no superovulation stimulation stage. The patient is either not prescribed drugs at all, or she takes them in minimal doses.

IVF stages in the natural cycle

• As with other artificial insemination programs, the process begins with a complete examination of partners and testing.
• Then, from the seventh day of the menstrual cycle, with the help of tests and ultrasound, the doctor controls the maturation of the follicle and the state of the endometrium. It is important to accurately track the maturation of the follicle, otherwise fertilization may not occur.
• By controlling the level of luteinizing hormone (LH) and estradiol, the fertility specialist determines the optimal day for puncture (when it is necessary to retrieve the egg). For each woman, the puncture time is set individually, since the length of the first phase of the menstrual cycle is different.
• In the natural cycle, often before the puncture, 36 hours before ovulation, hCG injections are given. If, nevertheless, the follicle has not increased to the desired size, an antagonist of GnRH and FSH is introduced.
• Fertilization of the egg with the sperm of a partner (donor) in a standard way or by ICSI.
• Cultivation of the embryo for 3-5 days.
• Transfer of the embryo into the uterine cavity 3-5 days after the puncture. This stage may not occur due to the lack of a quality embryo.
• The final stage with a positive result is confirmation of pregnancy 10-14 days after the embryo transfer.

IVF Protocol Schemes in the Natural Cycle

The IVF procedure at the EC has several protocol schemes, different depending on the chosen fertilization program.

• IVF in the natural cycle is the standard (described above).
• IVF programs with cryoprotocol, which consist in working with thawed biological material (oocytes, spermatozoa, embryos).
• Scheme without transfer. The ovum obtained by puncture is fertilized. The embryo is frozen and stored in a cryobank.
• Program using donor sperm (donor spermatozoa are used as male germ cells).
• No transfer with donor sperm. The egg is fertilized with donor sperm, cryopreserved, but not transferred to the uterus.
• The “Japanese” protocol – is that a woman receives eggs for several cycles, fertilizes and stores them frozen. After 4 cycles, there are already several embryos, and the expert selects the most complete ones for transfer.

Advantages and disadvantages

The IVF procedure in the natural cycle has its advantages and disadvantages. (2)

The pluses include:

• more comfortable emotional state of the patient;
• no risk of ovarian hyperstimulation syndrome;
• low probability of multiple pregnancy;
• reduced risk of preterm birth (with singleton pregnancy);
• the possibility of carrying out the procedure for several months in a row.

The procedure has fewer disadvantages.

Among them:

• lower performance (3);
• obtaining only one embryo and, as a result, the lack of choice of specimens of good and better quality (the accumulation of embryos helps to avoid this problem);
• forced cancellation of the procedure due to premature ovulation or due to the absence of an egg in the follicular fluid;
• egg immaturity.

Reviews of experts about IVF in the natural cycle

Comments obstetrician-gynecologist, reproductologist at Remedi Institute of Reproductive Medicine, member of RAHR, ESHRE Larisa Falaleeva.

– The IVF program in the natural cycle is carried out without the use of stimulation drugs (injections, tablets).

Only a trigger is prescribed (the preparation of the final maturation of cells), in order to program the puncture time and increase the likelihood of obtaining a mature cell.

There are features of this program:

• We can get only one cell, its quality is not known in advance (it may be immature, that is, unsuitable for fertilization). Or we may not get it at all. It all depends on whether it is embedded in the follicle or not.
• Efficiency depends on age. The older we get, the lower the chance of getting a genetically correct cell. Up to the age of 35, after ovarian surgery, this program can be successful. If the patient is older than 35 years, an attempt should be made to “accumulate” cells or embryos for the purpose of further testing for genetic changes before transfer (PGT-A).
• It is used in case of prohibition of stimulation. For example, in oncological patients, when the oncologist does not give the go-ahead for injectable drugs (shots). But even in this case, we try to stimulate them with drugs that are allowed for them and get more than 1 cell.
• We also conduct this program in extreme cases, according to the beliefs of patients. For example, because of a panic fear of injections, a categorical refusal to receive more than one cage for religion or any other reason.
• But do not forget that one follicle can carry a maximum of 1 cell, the quality of which can only be determined after it is received (puncture).

Reproductologist’s comment

“In a certain percentage of women, before the stage of transvaginal puncture, independent ovulation may occur,” notes obstetrician-gynecologist, reproductologist of the clinic LLC “ECO Center” in Volgograd Lyudmila Shurshina, — It is also possible to collect an immature egg. With the fertilization of only one egg, a good embryo suitable for transfer into the uterine cavity is not always obtained. Therefore, the effectiveness of the IVF program in the natural cycle is low 10-20%. However, for a certain group of patients, this can be a good chance for pregnancy.

Popular questions and answers

We answer the most popular questions about IVF in the natural cycle.

Sources of

1. Yakovenko E.M., Yakovenko S.A., In vitro fertilization (IVF) and other methods of overcoming infertility / 2016
2. Savvina O.V. childbearing: From former taboos to human enhancement technology: past, present and future of medical interventions in human reproduction / 2018
3. Kulakov V.I. In vitro fertilization and its new directions in the treatment of female and male infertility (theoretical and practical approaches) / 2000
4. Order of the Ministry of Health of the Federation No. 107. URL: https://minzdrav.gov-murman.ru/activities/akusherstvo/doc/prikaz-_-107n.pdf