IVF (in vitro fertilization) is one of the most widely used assisted reproductive treatments for individuals and couples experiencing difficulties in achieving a pregnancy. During IVF treatment, eggs are collected from the ovaries and fertilized with sperm under controlled laboratory conditions. The resulting embryos are then carefully monitored before a suitable embryo is transferred into the uterus.
IVF may be recommended for several causes of infertility, including blocked or damaged fallopian tubes, endometriosis, male factor infertility, reduced ovarian reserve or previous unsuccessful fertility treatments. The decision to proceed with IVF is always based on a detailed assessment of each patient’s medical history, fertility test results and individual circumstances.
What Is IVF (In Vitro Fertilization)?
IVF (in vitro fertilization) is an assisted reproductive treatment in which eggs are collected from the ovaries and fertilized with sperm in a laboratory. After fertilization, the developing embryos are monitored for several days before a suitable embryo is transferred into the uterus, where it may implant and develop into a pregnancy.
In a conventional IVF cycle, fertility medication is commonly used to stimulate the ovaries so that several eggs can mature during the same treatment cycle. The eggs are then retrieved through a transvaginal procedure and combined with sperm under controlled laboratory conditions.
When sperm quality, concentration or motility makes conventional fertilization less suitable, IVF may be combined with ICSI (Intracytoplasmic Sperm Injection). With ICSI, an embryologist injects a single sperm directly into an egg to assist fertilization.
The exact IVF protocol is individualized according to factors such as the woman’s age, ovarian reserve, medical history, fertility diagnosis and response to any previous treatments.
Who May Be Suitable for IVF?
IVF may be recommended when natural conception is difficult or when other fertility treatments are unlikely to provide a suitable chance of pregnancy. The decision is based on the cause of infertility, age, ovarian reserve, reproductive history and the results of fertility investigations.
IVF may be considered in cases such as:
- Blocked or damaged fallopian tubes.
- Endometriosis, particularly when it affects fertility.
- Male factor infertility, including certain problems with sperm count, movement or quality.
- Reduced ovarian reserve.
- Unexplained infertility.
- Previous unsuccessful fertility treatments, such as ovulation induction or IUI.
- Certain cases involving recurrent pregnancy loss, particularly when there is a specific genetic indication for IVF with preimplantation genetic testing.
- Treatment involving donor eggs or donor sperm.
- Situations in which a gestational carrier is medically indicated and permitted under the applicable legislation.
IVF is not automatically the first treatment for every fertility problem. A complete fertility assessment helps determine whether IVF is appropriate and which treatment protocol is most suitable for each individual or couple.
IVF Process Step by Step
1. Initial Fertility Consultation
The first step in IVF treatment is a detailed fertility consultation. During this appointment, the doctor reviews the medical and reproductive history of both partners, including previous pregnancies, fertility treatments, menstrual history, known medical conditions and any previous test results.
A transvaginal ultrasound may then be performed to assess the uterus, endometrium and ovaries. The ultrasound can also be used to measure the antral follicle count (AFC), which provides information about the number of small follicles visible in the ovaries and can help guide ovarian stimulation.
Depending on the individual case, additional fertility tests may be recommended, including hormonal blood tests such as Anti-Müllerian Hormone (AMH), FSH and estradiol, as well as semen analysis for the male partner.
The results of this initial assessment help the fertility specialist determine whether IVF is appropriate and select a treatment protocol tailored to the patient’s age, ovarian reserve, medical history and previous response to fertility treatment.
2. Ovarian Stimulation.
Ovarian stimulation is an important stage of IVF treatment. The goal is to encourage the ovaries to develop several mature follicles during the same cycle, increasing the number of eggs that may be available for fertilization. In most IVF cycles, this is achieved with injectable fertility medications called gonadotropins.
During stimulation, the response of the ovaries is monitored with transvaginal ultrasound scans and, when appropriate, blood tests. This allows the fertility specialist to assess follicular development and adjust the medication dose according to the patient’s response.
The stimulation protocol is individualized for each patient. Factors such as age, ovarian reserve, hormone levels, previous IVF response and the risk of ovarian hyperstimulation syndrome (OHSS) may influence the type and dose of medication selected.
When the follicles have developed sufficiently, a final “trigger” medication is given to support the last stage of egg maturation before egg retrieval.
3. Egg Retrieval.
Egg retrieval, also known as oocyte retrieval, is performed once the follicles have reached the appropriate stage of development. The procedure is usually scheduled after the final trigger medication, which supports the last stage of egg maturation.
During egg retrieval, a fine needle is passed through the vaginal wall into the ovaries under transvaginal ultrasound guidance. Follicular fluid is gently aspirated, and the embryology laboratory examines it to identify the collected eggs. The procedure is commonly performed under light sedation and usually takes around 20–30 minutes.
After the procedure, the patient remains in the recovery area for a short period before returning home. Mild pelvic discomfort, cramping or light vaginal spotting may occur for a short time after egg retrieval.
The number of eggs collected varies from patient to patient and depends on factors such as ovarian reserve, age and response to ovarian stimulation. Not every follicle seen during monitoring will necessarily contain an egg.
4. Fertilization and ICSI.
After egg retrieval, the collected eggs are transferred to the embryology laboratory, where they are prepared for fertilization. The fertilization method used depends mainly on sperm quality and the individual characteristics of the couple.
In conventional IVF, the eggs are placed together with prepared sperm under controlled laboratory conditions, allowing fertilization to occur naturally in the culture dish.
When there is a significant male factor, such as a very low sperm count, reduced sperm motility or previous poor fertilization with standard IVF, ICSI (Intracytoplasmic Sperm Injection) may be recommended. With ICSI, an embryologist selects a single sperm and injects it directly into a mature egg.
The following day, the embryology team checks the eggs for signs of successful fertilization. The resulting embryos are then monitored as they continue to develop in the laboratory before the next stage of treatment.
ICSI is not automatically necessary for every IVF cycle. The decision to use conventional IVF or ICSI is made according to the semen analysis, previous treatment history and the specific clinical indications of each case.
5. Embryo Development.
After successful fertilization, the embryos remain in the laboratory, where their development is carefully monitored by the embryology team. During the first few days, the cells of the embryo divide progressively as it moves through different stages of development.
Embryos may be assessed at the cleavage stage, usually around day 2 or 3, or they may continue developing until the blastocyst stage, which is generally reached around day 5 or 6 after fertilization.
Throughout this period, embryologists evaluate characteristics such as cell division and overall embryo development. This information helps determine which embryo may be most suitable for transfer and whether any additional suitable embryos can be considered for cryopreservation.
Not every fertilized egg will continue developing to the blastocyst stage, and the number and quality of embryos can vary considerably between IVF cycles.
The timing of embryo transfer is therefore individualized according to the number and development of the available embryos, as well as the patient’s treatment plan.
6. Embryo Transfer.
Embryo transfer is the stage of IVF treatment in which a selected embryo is placed into the uterus. In a fresh IVF cycle, this usually takes place a few days after fertilization, depending on embryo development and the individual treatment plan.
The procedure is usually simple and does not require anaesthesia. A thin catheter is gently passed through the cervix into the uterus, and the embryo is carefully transferred into the uterine cavity.
The number of embryos transferred is determined individually, taking into account factors such as the woman’s age, embryo quality, previous IVF history and the risk of multiple pregnancy. In many cases, transferring a single suitable embryo is preferred in order to reduce the likelihood of twins or higher-order multiple pregnancy.
Any additional suitable embryos that are not transferred may be cryopreserved for possible use in a future frozen embryo transfer cycle.
In some IVF cycles, all suitable embryos may be frozen instead of performing a fresh transfer. The embryo transfer then takes place at a later stage, once the endometrium has been appropriately prepared.
What Happens After Embryo Transfer?
After embryo transfer, the patient can usually return to normal daily activities. Prolonged bed rest is not generally required, although strenuous physical activity may be limited according to the fertility specialist’s instructions.
Medication prescribed after embryo transfer, commonly including progesterone for luteal phase support, should be continued exactly as instructed. The duration of this treatment varies according to the IVF protocol and the individual patient.
A pregnancy test is performed on the date recommended by the fertility clinic. The exact timing can vary between treatment protocols, so testing too early should be avoided, as fertility medications may affect the result.
If the pregnancy test is positive, an ultrasound is usually scheduled during the following weeks to confirm that the pregnancy is developing in the uterus and to assess its early progress.
Patients should contact their fertility specialist if they experience significant bleeding, severe or one-sided abdominal pain, fainting or other concerning symptoms after embryo transfer.
How Long Does an IVF Cycle Take?
The duration of an IVF cycle varies depending on the treatment protocol and the individual response to medication. In general, a complete IVF cycle takes approximately three to six weeks, although some protocols may take longer.
The process typically includes ovarian stimulation, monitoring with ultrasound scans and blood tests, the final trigger injection, egg retrieval, fertilization in the laboratory and embryo development. In a fresh IVF cycle, embryo transfer usually takes place a few days after egg retrieval.
Some patients may follow a shorter stimulation protocol, while others may require additional preparation before ovarian stimulation begins. The exact schedule therefore depends on factors such as age, ovarian reserve, hormone levels and the selected IVF protocol.
In a freeze-all cycle, suitable embryos are cryopreserved rather than transferred immediately. The frozen embryo transfer is then planned in a later cycle, meaning the overall time between starting IVF and embryo transfer may be longer.
Before treatment begins, each patient receives an individualized IVF timeline based on their fertility assessment and treatment plan.
IVF Treatment with Dr. Panagiotis Kaliantzis
Dr. Panagiotis Kaliantzis MD, MRCOG, DFFP is an Obstetrician, Gynaecologist and Fertility Specialist providing individualized fertility assessment and IVF treatment in Athens and Tripoli.
Each IVF treatment plan begins with a detailed evaluation of the patient or couple, taking into account factors such as age, ovarian reserve, medical history, previous fertility treatments and the underlying cause of infertility. Based on these findings, the most appropriate IVF protocol is selected and adjusted according to the patient’s response during treatment.
Patients are supported throughout every stage of the IVF process, from the initial consultation and ovarian stimulation to egg retrieval, fertilization, embryo development and embryo transfer. The aim is to provide clear information at every step and develop a treatment plan tailored to the individual needs of each case.
Frequently Asked Questions About IVF
What is IVF and how does it work?
IVF (in vitro fertilization) is a fertility treatment in which eggs are collected from the ovaries and fertilized with sperm in a laboratory. The resulting embryos are monitored before a suitable embryo is transferred into the uterus.
Who is a good candidate for IVF?
IVF may be suitable for people with different causes of infertility, including blocked or damaged fallopian tubes, endometriosis, male factor infertility or previous unsuccessful fertility treatments. Whether IVF is appropriate depends on the individual fertility assessment, medical history, age and reproductive circumstances.
How long does IVF treatment take?
A full IVF cycle commonly takes around three to six weeks, although the exact duration depends on the treatment protocol and whether a fresh or frozen embryo transfer is planned.
Is egg retrieval painful?
Egg retrieval is performed through the vagina using ultrasound guidance and is usually carried out with sedation. The procedure itself commonly takes around 20 minutes. Some patients may experience mild cramping or discomfort afterwards.
What is the difference between IVF and ICSI?
In conventional IVF, eggs are placed together with prepared sperm in the laboratory to allow fertilization to occur. With ICSI, an embryologist injects a single sperm directly into a mature egg. ICSI may be recommended when there are significant problems with sperm number or motility or for other specific clinical indications.
When should I take a pregnancy test after embryo transfer?
The fertility clinic will provide a specific date for the pregnancy test after embryo transfer. Testing too early should be avoided because medication used during IVF, particularly the trigger injection, may affect the result. Patients should follow the testing schedule provided by their fertility specialist.
